Convert FWL_ERR into an enum class.

This Cl updates FWL_ERR to be an FWL_Error enum class. It removes FX_ERR and
replaces it with FWL_Error as well as the values were the same.

There were many places where we either returned other values for FWL_ERR
results.

This Cl is the same as: https://codereview.chromium.org/1943413002/ but I seem
to have messed up the base URL in that one.

TBR=tsepez@chromium.org

Review-Url: https://codereview.chromium.org/1952693003

38 files changed, 1129 insertions, 1095 deletions

diff --git a/xfa/fwl/basewidget/fwl_barcodeimp.cpp b/xfa/fwl/basewidget/fwl_barcodeimp.cpp
index d4589e39c1..ce9d083d83 100644
--- a/xfa/fwl/basewidget/fwl_barcodeimp.cpp
+++ b/xfa/fwl/basewidget/fwl_barcodeimp.cpp
@@ -38,45 +38,45 @@ CFWL_BarcodeImp::CFWL_BarcodeImp(const CFWL_WidgetImpProperties& properties,
 CFWL_BarcodeImp::~CFWL_BarcodeImp() {
   ReleaseBarcodeEngine();
 }
-FWL_ERR CFWL_BarcodeImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_BarcodeImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_Barcode;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_BarcodeImp::GetClassID() const {
   return FWL_CLASSHASH_Barcode;
 }
-FWL_ERR CFWL_BarcodeImp::Initialize() {
+FWL_Error CFWL_BarcodeImp::Initialize() {
   if (!m_pDelegate) {
     m_pDelegate = new CFWL_BarcodeImpDelegate(this);
   }
-  if (CFWL_EditImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
-  return FWL_ERR_Succeeded;
+  if (CFWL_EditImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_BarcodeImp::Finalize() {
+FWL_Error CFWL_BarcodeImp::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   ReleaseBarcodeEngine();
   return CFWL_EditImp::Finalize();
 }
-FWL_ERR CFWL_BarcodeImp::Update() {
+FWL_Error CFWL_BarcodeImp::Update() {
   if (IsLocked()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
-  FWL_ERR ret = CFWL_EditImp::Update();
+  FWL_Error ret = CFWL_EditImp::Update();
   GenerateBarcodeImageCache();
   return ret;
 }
-FWL_ERR CFWL_BarcodeImp::DrawWidget(CFX_Graphics* pGraphics,
-                                    const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_BarcodeImp::DrawWidget(CFX_Graphics* pGraphics,
+                                      const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if ((m_pProperties->m_dwStates & FWL_WGTSTATE_Focused) == 0) {
     GenerateBarcodeImageCache();
     if (!m_pBarcodeEngine || (m_dwStatus & XFA_BCS_EncodeSuccess) == 0) {
-      return FWL_ERR_Succeeded;
+      return FWL_Error::Succeeded;
     }
     CFX_Matrix mt;
     mt.e = m_rtClient.left;
@@ -87,9 +87,9 @@ FWL_ERR CFWL_BarcodeImp::DrawWidget(CFX_Graphics* pGraphics,
     int32_t errorCode = 0;
     if (!m_pBarcodeEngine->RenderDevice(pGraphics->GetRenderDevice(), pMatrix,
                                         errorCode)) {
-      return FWL_ERR_Indefinite;
+      return FWL_Error::Indefinite;
     }
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Succeeded;
   }
   return CFWL_EditImp::DrawWidget(pGraphics, pMatrix);
 }
@@ -105,7 +105,7 @@ void CFWL_BarcodeImp::GenerateBarcodeImageCache() {
   if (!m_pBarcodeEngine)
     return;
   CFX_WideString wsText;
-  if (GetText(wsText) != FWL_ERR_Succeeded)
+  if (GetText(wsText) != FWL_Error::Succeeded)
     return;
   CFWL_ThemePart part;
   part.m_pWidget = m_pInterface;
@@ -200,7 +200,7 @@ void CFWL_BarcodeImp::SetType(BC_TYPE type) {
   m_type = type;
   m_dwStatus = XFA_BCS_NeedUpdate;
 }
-FWL_ERR CFWL_BarcodeImp::SetText(const CFX_WideString& wsText) {
+FWL_Error CFWL_BarcodeImp::SetText(const CFX_WideString& wsText) {
   ReleaseBarcodeEngine();
   m_dwStatus = XFA_BCS_NeedUpdate;
   return CFWL_EditImp::SetText(wsText);
@@ -220,11 +220,11 @@ FX_BOOL CFWL_BarcodeImp::IsProtectedType() {
 CFWL_BarcodeImpDelegate::CFWL_BarcodeImpDelegate(CFWL_BarcodeImp* pOwner)
     : CFWL_EditImpDelegate(pOwner) {}
 
-FWL_ERR CFWL_BarcodeImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
+void CFWL_BarcodeImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
   if (pEvent->GetClassID() == CFWL_EventType::TextChanged) {
     CFWL_BarcodeImp* pOwner = static_cast<CFWL_BarcodeImp*>(m_pOwner);
     pOwner->ReleaseBarcodeEngine();
     pOwner->m_dwStatus = XFA_BCS_NeedUpdate;
   }
-  return CFWL_EditImpDelegate::OnProcessEvent(pEvent);
+  CFWL_EditImpDelegate::OnProcessEvent(pEvent);
 }
diff --git a/xfa/fwl/basewidget/fwl_barcodeimp.h b/xfa/fwl/basewidget/fwl_barcodeimp.h
index eacecc3c4e..68c017e63e 100644
--- a/xfa/fwl/basewidget/fwl_barcodeimp.h
+++ b/xfa/fwl/basewidget/fwl_barcodeimp.h
@@ -25,14 +25,14 @@ class CFWL_BarcodeImp : public CFWL_EditImp {
                   IFWL_Widget* pOuter);
   ~CFWL_BarcodeImp() override;
 
-  FWL_ERR GetClassName(CFX_WideString& wsClass) const override;
+  FWL_Error GetClassName(CFX_WideString& wsClass) const override;
   uint32_t GetClassID() const override;
-  FWL_ERR Initialize() override;
-  FWL_ERR Finalize() override;
-  FWL_ERR Update() override;
-  FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                     const CFX_Matrix* pMatrix = nullptr) override;
-  FWL_ERR SetText(const CFX_WideString& wsText) override;
+  FWL_Error Initialize() override;
+  FWL_Error Finalize() override;
+  FWL_Error Update() override;
+  FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                       const CFX_Matrix* pMatrix = nullptr) override;
+  FWL_Error SetText(const CFX_WideString& wsText) override;
   void SetType(BC_TYPE type);
   FX_BOOL IsProtectedType();
 
@@ -51,7 +51,7 @@ class CFWL_BarcodeImp : public CFWL_EditImp {
 class CFWL_BarcodeImpDelegate : public CFWL_EditImpDelegate {
  public:
   CFWL_BarcodeImpDelegate(CFWL_BarcodeImp* pOwner);
-  FWL_ERR OnProcessEvent(CFWL_Event* pEvent) override;
+  void OnProcessEvent(CFWL_Event* pEvent) override;
 };
 
 #endif  // XFA_FWL_BASEWIDGET_FWL_BARCODEIMP_H_
diff --git a/xfa/fwl/basewidget/fwl_caretimp.cpp b/xfa/fwl/basewidget/fwl_caretimp.cpp
index 23a5213a4d..2b4a67cb1a 100644
--- a/xfa/fwl/basewidget/fwl_caretimp.cpp
+++ b/xfa/fwl/basewidget/fwl_caretimp.cpp
@@ -25,13 +25,13 @@ IFWL_Caret::IFWL_Caret() {}
 void IFWL_Caret::ShowCaret(FX_BOOL bFlag) {
   static_cast<CFWL_CaretImp*>(GetImpl())->ShowCaret(bFlag);
 }
-FWL_ERR IFWL_Caret::GetFrequency(uint32_t& elapse) {
+FWL_Error IFWL_Caret::GetFrequency(uint32_t& elapse) {
   return static_cast<CFWL_CaretImp*>(GetImpl())->GetFrequency(elapse);
 }
-FWL_ERR IFWL_Caret::SetFrequency(uint32_t elapse) {
+FWL_Error IFWL_Caret::SetFrequency(uint32_t elapse) {
   return static_cast<CFWL_CaretImp*>(GetImpl())->SetFrequency(elapse);
 }
-FWL_ERR IFWL_Caret::SetColor(CFX_Color crFill) {
+FWL_Error IFWL_Caret::SetColor(CFX_Color crFill) {
   return static_cast<CFWL_CaretImp*>(GetImpl())->SetColor(crFill);
 }
 
@@ -49,20 +49,20 @@ CFWL_CaretImp::~CFWL_CaretImp() {
   delete m_pTimer;
 }
 
-FWL_ERR CFWL_CaretImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_CaretImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_Caret;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_CaretImp::GetClassID() const {
   return FWL_CLASSHASH_Caret;
 }
-FWL_ERR CFWL_CaretImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_CaretImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_CaretImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_CaretImp::Finalize() {
+FWL_Error CFWL_CaretImp::Finalize() {
   if (m_hTimer) {
     FWL_StopTimer(m_hTimer);
     m_hTimer = NULL;
@@ -71,16 +71,17 @@ FWL_ERR CFWL_CaretImp::Finalize() {
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_CaretImp::DrawWidget(CFX_Graphics* pGraphics,
-                                  const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_CaretImp::DrawWidget(CFX_Graphics* pGraphics,
+                                    const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
+
   DrawCaretBK(pGraphics, m_pProperties->m_pThemeProvider, pMatrix);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 
 void CFWL_CaretImp::ShowCaret(FX_BOOL bFlag) {
@@ -93,22 +94,23 @@ void CFWL_CaretImp::ShowCaret(FX_BOOL bFlag) {
 
   SetStates(FWL_WGTSTATE_Invisible, !bFlag);
 }
-FWL_ERR CFWL_CaretImp::GetFrequency(uint32_t& elapse) {
+FWL_Error CFWL_CaretImp::GetFrequency(uint32_t& elapse) {
   elapse = m_dwElapse;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_CaretImp::SetFrequency(uint32_t elapse) {
+FWL_Error CFWL_CaretImp::SetFrequency(uint32_t elapse) {
   m_dwElapse = elapse;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_CaretImp::SetColor(CFX_Color crFill) {
+FWL_Error CFWL_CaretImp::SetColor(CFX_Color crFill) {
   m_bSetColor = TRUE;
   m_crFill = crFill;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FX_BOOL CFWL_CaretImp::DrawCaretBK(CFX_Graphics* pGraphics,
-                                   IFWL_ThemeProvider* pTheme,
-                                   const CFX_Matrix* pMatrix) {
+
+void CFWL_CaretImp::DrawCaretBK(CFX_Graphics* pGraphics,
+                                IFWL_ThemeProvider* pTheme,
+                                const CFX_Matrix* pMatrix) {
   CFX_RectF rect;
   GetWidgetRect(rect);
   rect.Set(0, 0, rect.width, rect.height);
@@ -116,19 +118,17 @@ FX_BOOL CFWL_CaretImp::DrawCaretBK(CFX_Graphics* pGraphics,
   param.m_pWidget = m_pInterface;
   param.m_pGraphics = pGraphics;
   param.m_rtPart = rect;
-  if (m_bSetColor) {
+  if (m_bSetColor)
     param.m_pData = &m_crFill;
-  }
-  if (!(m_pProperties->m_dwStates & FWL_STATE_CAT_HightLight)) {
-    return FWL_ERR_Succeeded;
-  }
+  if (!(m_pProperties->m_dwStates & FWL_STATE_CAT_HightLight))
+    return;
+
   param.m_iPart = CFWL_Part::Background;
   param.m_dwStates = CFWL_PartState_HightLight;
-  if (pMatrix) {
+  if (pMatrix)
     param.m_matrix.Concat(*pMatrix);
-  }
+
   pTheme->DrawBackground(&param);
-  return FWL_ERR_Succeeded;
 }
 
 CFWL_CaretImp::CFWL_CaretTimer::CFWL_CaretTimer(CFWL_CaretImp* pCaret)
@@ -146,12 +146,13 @@ int32_t CFWL_CaretImp::CFWL_CaretTimer::Run(FWL_HTIMER hTimer) {
   m_pCaret->Repaint(&rt);
   return 1;
 }
+
 CFWL_CaretImpDelegate::CFWL_CaretImpDelegate(CFWL_CaretImp* pOwner)
     : m_pOwner(pOwner) {}
-int32_t CFWL_CaretImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
-  return 1;
-}
-FWL_ERR CFWL_CaretImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                            const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+
+void CFWL_CaretImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {}
+
+void CFWL_CaretImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                         const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
diff --git a/xfa/fwl/basewidget/fwl_caretimp.h b/xfa/fwl/basewidget/fwl_caretimp.h
index 81d6e45449..c579beeed3 100644
--- a/xfa/fwl/basewidget/fwl_caretimp.h
+++ b/xfa/fwl/basewidget/fwl_caretimp.h
@@ -21,24 +21,24 @@ class CFWL_CaretImp : public CFWL_WidgetImp {
                 IFWL_Widget* pOuter);
   virtual ~CFWL_CaretImp();
 
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
 
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
 
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
 
   virtual void ShowCaret(FX_BOOL bFlag = TRUE);
-  virtual FWL_ERR GetFrequency(uint32_t& elapse);
-  virtual FWL_ERR SetFrequency(uint32_t elapse);
-  virtual FWL_ERR SetColor(CFX_Color crFill);
+  virtual FWL_Error GetFrequency(uint32_t& elapse);
+  virtual FWL_Error SetFrequency(uint32_t elapse);
+  virtual FWL_Error SetColor(CFX_Color crFill);
 
  protected:
-  FX_BOOL DrawCaretBK(CFX_Graphics* pGraphics,
-                      IFWL_ThemeProvider* pTheme,
-                      const CFX_Matrix* pMatrix);
+  void DrawCaretBK(CFX_Graphics* pGraphics,
+                   IFWL_ThemeProvider* pTheme,
+                   const CFX_Matrix* pMatrix);
   class CFWL_CaretTimer : public IFWL_Timer {
    public:
     explicit CFWL_CaretTimer(CFWL_CaretImp* pCaret);
@@ -57,9 +57,9 @@ class CFWL_CaretImp : public CFWL_WidgetImp {
 class CFWL_CaretImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_CaretImpDelegate(CFWL_CaretImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   CFWL_CaretImp* m_pOwner;
diff --git a/xfa/fwl/basewidget/fwl_checkboximp.cpp b/xfa/fwl/basewidget/fwl_checkboximp.cpp
index ba63e2f663..a45c639450 100644
--- a/xfa/fwl/basewidget/fwl_checkboximp.cpp
+++ b/xfa/fwl/basewidget/fwl_checkboximp.cpp
@@ -37,7 +37,7 @@ IFWL_CheckBox::IFWL_CheckBox() {}
 int32_t IFWL_CheckBox::GetCheckState() {
   return static_cast<CFWL_CheckBoxImp*>(GetImpl())->GetCheckState();
 }
-FWL_ERR IFWL_CheckBox::SetCheckState(int32_t iCheck) {
+FWL_Error IFWL_CheckBox::SetCheckState(int32_t iCheck) {
   return static_cast<CFWL_CheckBoxImp*>(GetImpl())->SetCheckState(iCheck);
 }
 
@@ -53,33 +53,33 @@ CFWL_CheckBoxImp::CFWL_CheckBoxImp(const CFWL_WidgetImpProperties& properties,
   m_rtFocus.Reset();
 }
 CFWL_CheckBoxImp::~CFWL_CheckBoxImp() {}
-FWL_ERR CFWL_CheckBoxImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_CheckBoxImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_CheckBox;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_CheckBoxImp::GetClassID() const {
   return FWL_CLASSHASH_CheckBox;
 }
-FWL_ERR CFWL_CheckBoxImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_CheckBoxImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_CheckBoxImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_CheckBoxImp::Finalize() {
+FWL_Error CFWL_CheckBoxImp::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_CheckBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
+FWL_Error CFWL_CheckBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   if (bAutoSize) {
     rect.Set(0, 0, 0, 0);
     if (!m_pProperties->m_pThemeProvider)
       m_pProperties->m_pThemeProvider = GetAvailableTheme();
     if (!m_pProperties->m_pThemeProvider)
-      return FWL_ERR_Indefinite;
+      return FWL_Error::Indefinite;
     if (!m_pProperties->m_pDataProvider)
-      return FWL_ERR_Indefinite;
+      return FWL_Error::Indefinite;
     CFX_WideString wsCaption;
     m_pProperties->m_pDataProvider->GetCaption(m_pInterface, wsCaption);
     if (wsCaption.GetLength() > 0) {
@@ -100,25 +100,25 @@ FWL_ERR CFWL_CheckBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   } else {
     rect = m_pProperties->m_rtWidget;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_CheckBoxImp::Update() {
+FWL_Error CFWL_CheckBoxImp::Update() {
   if (IsLocked()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   if (!m_pProperties->m_pThemeProvider) {
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
   }
   UpdateTextOutStyles();
   Layout();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_CheckBoxImp::DrawWidget(CFX_Graphics* pGraphics,
-                                     const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_CheckBoxImp::DrawWidget(CFX_Graphics* pGraphics,
+                                       const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   IFWL_ThemeProvider* pTheme = m_pProperties->m_pThemeProvider;
   if (HasBorder()) {
     DrawBorder(pGraphics, CFWL_Part::Border, m_pProperties->m_pThemeProvider,
@@ -147,13 +147,13 @@ FWL_ERR CFWL_CheckBoxImp::DrawWidget(CFX_Graphics* pGraphics,
     pTheme->DrawBackground(&param);
   }
   if (!m_pProperties->m_pDataProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   {
     CFX_WideString wsCaption;
     m_pProperties->m_pDataProvider->GetCaption(m_pInterface, wsCaption);
     int32_t iLen = wsCaption.GetLength();
     if (iLen <= 0)
-      return FWL_ERR_Indefinite;
+      return FWL_Error::Indefinite;
     CFWL_ThemeText textParam;
     textParam.m_pWidget = m_pInterface;
     textParam.m_iPart = CFWL_Part::Caption;
@@ -168,7 +168,7 @@ FWL_ERR CFWL_CheckBoxImp::DrawWidget(CFX_Graphics* pGraphics,
     textParam.m_iTTOAlign = m_iTTOAlign;
     pTheme->DrawText(&textParam);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 int32_t CFWL_CheckBoxImp::GetCheckState() {
   if ((m_pProperties->m_dwStyleExes & FWL_STYLEEXT_CKB_3State) &&
@@ -182,7 +182,7 @@ int32_t CFWL_CheckBoxImp::GetCheckState() {
   }
   return 0;
 }
-FWL_ERR CFWL_CheckBoxImp::SetCheckState(int32_t iCheck) {
+FWL_Error CFWL_CheckBoxImp::SetCheckState(int32_t iCheck) {
   m_pProperties->m_dwStates &= ~FWL_STATE_CKB_CheckMask;
   switch (iCheck) {
     case 0: {
@@ -201,7 +201,7 @@ FWL_ERR CFWL_CheckBoxImp::SetCheckState(int32_t iCheck) {
     default: {}
   }
   Repaint(&m_rtClient);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 void CFWL_CheckBoxImp::Layout() {
   int32_t width = int32_t(m_pProperties->m_rtWidget.width + 0.5f);
@@ -413,11 +413,10 @@ void CFWL_CheckBoxImp::NextStates() {
 CFWL_CheckBoxImpDelegate::CFWL_CheckBoxImpDelegate(CFWL_CheckBoxImp* pOwner)
     : m_pOwner(pOwner) {}
 
-int32_t CFWL_CheckBoxImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+void CFWL_CheckBoxImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
 
-  int32_t iRet = 1;
   switch (pMessage->GetClassID()) {
     case CFWL_MessageType::Activate: {
       OnActivate(pMessage);
@@ -462,18 +461,18 @@ int32_t CFWL_CheckBoxImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
       break;
     }
     default: {
-      iRet = 0;
       break;
     }
   }
 
   CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
-  return iRet;
 }
-FWL_ERR CFWL_CheckBoxImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                               const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+
+void CFWL_CheckBoxImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                            const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
+
 void CFWL_CheckBoxImpDelegate::OnActivate(CFWL_Message* pMsg) {
   m_pOwner->m_pProperties->m_dwStates &= ~FWL_WGTSTATE_Deactivated;
   m_pOwner->Repaint(&(m_pOwner->m_rtClient));
diff --git a/xfa/fwl/basewidget/fwl_checkboximp.h b/xfa/fwl/basewidget/fwl_checkboximp.h
index fe0ebb05cb..cc5474db9a 100644
--- a/xfa/fwl/basewidget/fwl_checkboximp.h
+++ b/xfa/fwl/basewidget/fwl_checkboximp.h
@@ -19,16 +19,16 @@ class CFWL_CheckBoxImp : public CFWL_WidgetImp {
   CFWL_CheckBoxImp(const CFWL_WidgetImpProperties& properties,
                    IFWL_Widget* pOuter);
   ~CFWL_CheckBoxImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  virtual FWL_ERR Update();
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error Update();
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
   virtual int32_t GetCheckState();
-  virtual FWL_ERR SetCheckState(int32_t iCheck);
+  virtual FWL_Error SetCheckState(int32_t iCheck);
 
  protected:
   void Layout();
@@ -47,9 +47,9 @@ class CFWL_CheckBoxImp : public CFWL_WidgetImp {
 class CFWL_CheckBoxImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_CheckBoxImpDelegate(CFWL_CheckBoxImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void OnActivate(CFWL_Message* pMsg);
diff --git a/xfa/fwl/basewidget/fwl_comboboximp.cpp b/xfa/fwl/basewidget/fwl_comboboximp.cpp
index 5b3e7c7c35..7368f7bbbd 100644
--- a/xfa/fwl/basewidget/fwl_comboboximp.cpp
+++ b/xfa/fwl/basewidget/fwl_comboboximp.cpp
@@ -37,22 +37,22 @@ IFWL_ComboBox::IFWL_ComboBox() {}
 int32_t IFWL_ComboBox::GetCurSel() {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->GetCurSel();
 }
-FWL_ERR IFWL_ComboBox::SetCurSel(int32_t iSel) {
+FWL_Error IFWL_ComboBox::SetCurSel(int32_t iSel) {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->SetCurSel(iSel);
 }
-FWL_ERR IFWL_ComboBox::SetEditText(const CFX_WideString& wsText) {
+FWL_Error IFWL_ComboBox::SetEditText(const CFX_WideString& wsText) {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->SetEditText(wsText);
 }
 int32_t IFWL_ComboBox::GetEditTextLength() const {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->GetEditTextLength();
 }
-FWL_ERR IFWL_ComboBox::GetEditText(CFX_WideString& wsText,
-                                   int32_t nStart,
-                                   int32_t nCount) const {
+FWL_Error IFWL_ComboBox::GetEditText(CFX_WideString& wsText,
+                                     int32_t nStart,
+                                     int32_t nCount) const {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())
       ->GetEditText(wsText, nStart, nCount);
 }
-FWL_ERR IFWL_ComboBox::SetEditSelRange(int32_t nStart, int32_t nCount) {
+FWL_Error IFWL_ComboBox::SetEditSelRange(int32_t nStart, int32_t nCount) {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())
       ->SetEditSelRange(nStart, nCount);
 }
@@ -63,10 +63,10 @@ int32_t IFWL_ComboBox::GetEditSelRange(int32_t nIndex, int32_t& nStart) {
 int32_t IFWL_ComboBox::GetEditLimit() {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->GetEditLimit();
 }
-FWL_ERR IFWL_ComboBox::SetEditLimit(int32_t nLimit) {
+FWL_Error IFWL_ComboBox::SetEditLimit(int32_t nLimit) {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->SetEditLimit(nLimit);
 }
-FWL_ERR IFWL_ComboBox::EditDoClipboard(int32_t iCmd) {
+FWL_Error IFWL_ComboBox::EditDoClipboard(int32_t iCmd) {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->EditDoClipboard(iCmd);
 }
 FX_BOOL IFWL_ComboBox::EditRedo(const CFX_ByteStringC& bsRecord) {
@@ -81,7 +81,7 @@ IFWL_ListBox* IFWL_ComboBox::GetListBoxt() {
 FX_BOOL IFWL_ComboBox::AfterFocusShowDropList() {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->AfterFocusShowDropList();
 }
-FX_ERR IFWL_ComboBox::OpenDropDownList(FX_BOOL bActivate) {
+FWL_Error IFWL_ComboBox::OpenDropDownList(FX_BOOL bActivate) {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->OpenDropDownList(bActivate);
 }
 FX_BOOL IFWL_ComboBox::EditCanUndo() {
@@ -123,11 +123,11 @@ FX_BOOL IFWL_ComboBox::EditDelete() {
 FX_BOOL IFWL_ComboBox::EditDeSelect() {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->EditDeSelect();
 }
-FWL_ERR IFWL_ComboBox::GetBBox(CFX_RectF& rect) {
+FWL_Error IFWL_ComboBox::GetBBox(CFX_RectF& rect) {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())->GetBBox(rect);
 }
-FWL_ERR IFWL_ComboBox::EditModifyStylesEx(uint32_t dwStylesExAdded,
-                                          uint32_t dwStylesExRemoved) {
+FWL_Error IFWL_ComboBox::EditModifyStylesEx(uint32_t dwStylesExAdded,
+                                            uint32_t dwStylesExRemoved) {
   return static_cast<CFWL_ComboBoxImp*>(GetImpl())
       ->EditModifyStylesEx(dwStylesExAdded, dwStylesExRemoved);
 }
@@ -141,9 +141,9 @@ CFWL_ComboEditImp::CFWL_ComboEditImp(const CFWL_WidgetImpProperties& properties,
 CFWL_ComboEditImpDelegate::CFWL_ComboEditImpDelegate(CFWL_ComboEditImp* pOwner)
     : CFWL_EditImpDelegate(pOwner), m_pOwner(pOwner) {}
 
-int32_t CFWL_ComboEditImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+void CFWL_ComboEditImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
 
   FX_BOOL backDefault = TRUE;
   switch (pMessage->GetClassID()) {
@@ -169,9 +169,8 @@ int32_t CFWL_ComboEditImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
     default:
       break;
   }
-  if (!backDefault)
-    return 1;
-  return CFWL_EditImpDelegate::OnProcessMessage(pMessage);
+  if (backDefault)
+    CFWL_EditImpDelegate::OnProcessMessage(pMessage);
 }
 
 void CFWL_ComboEditImp::ClearSelected() {
@@ -202,14 +201,14 @@ CFWL_ComboListImp::CFWL_ComboListImp(const CFWL_WidgetImpProperties& properties,
     : CFWL_ListBoxImp(properties, pOuter), m_bNotifyOwner(TRUE) {
   ASSERT(pOuter != NULL);
 }
-FWL_ERR CFWL_ComboListImp::Initialize() {
-  if (CFWL_ListBoxImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_ComboListImp::Initialize() {
+  if (CFWL_ListBoxImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   delete m_pDelegate;
   m_pDelegate = new CFWL_ComboListImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ComboListImp::Finalize() {
+FWL_Error CFWL_ComboListImp::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_ListBoxImp::Finalize();
@@ -286,9 +285,9 @@ void CFWL_ComboListImp::SetFocus(FX_BOOL bSet) {
 CFWL_ComboListImpDelegate::CFWL_ComboListImpDelegate(CFWL_ComboListImp* pOwner)
     : CFWL_ListBoxImpDelegate(pOwner), m_pOwner(pOwner) {}
 
-int32_t CFWL_ComboListImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+void CFWL_ComboListImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
 
   CFWL_MessageType dwHashCode = pMessage->GetClassID();
   FX_BOOL backDefault = TRUE;
@@ -305,7 +304,8 @@ int32_t CFWL_ComboListImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
         pMsg->m_fy -= rect.top;
         IFWL_WidgetDelegate* pDelegate =
             m_pOwner->m_pVertScrollBar->SetDelegate(NULL);
-        return pDelegate->OnProcessMessage(pMsg);
+        pDelegate->OnProcessMessage(pMsg);
+        return;
       }
     }
     switch (pMsg->m_dwCmd) {
@@ -330,9 +330,8 @@ int32_t CFWL_ComboListImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   } else if (dwHashCode == CFWL_MessageType::Key) {
     backDefault = !OnDropListKey(static_cast<CFWL_MsgKey*>(pMessage));
   }
-  if (!backDefault)
-    return 1;
-  return CFWL_ListBoxImpDelegate::OnProcessMessage(pMessage);
+  if (backDefault)
+    CFWL_ListBoxImpDelegate::OnProcessMessage(pMessage);
 }
 
 void CFWL_ComboListImpDelegate::OnDropListFocusChanged(CFWL_Message* pMsg,
@@ -483,27 +482,31 @@ CFWL_ComboBoxImp::CFWL_ComboBoxImp(const CFWL_WidgetImpProperties& properties,
   m_rtBtn.Reset();
   m_rtHandler.Reset();
 }
+
 CFWL_ComboBoxImp::~CFWL_ComboBoxImp() {}
-FWL_ERR CFWL_ComboBoxImp::GetClassName(CFX_WideString& wsClass) const {
+
+FWL_Error CFWL_ComboBoxImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_ComboBox;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
+
 uint32_t CFWL_ComboBoxImp::GetClassID() const {
   return FWL_CLASSHASH_ComboBox;
 }
-FWL_ERR CFWL_ComboBoxImp::Initialize() {
-  if (m_pWidgetMgr->IsFormDisabled()) {
+
+FWL_Error CFWL_ComboBoxImp::Initialize() {
+  if (m_pWidgetMgr->IsFormDisabled())
     return DisForm_Initialize();
-  }
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_WGTSTATE_Invisible;  // Probably a bug; not a FWL_ERR_ value.
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
+
   m_pDelegate = new CFWL_ComboBoxImpDelegate(this);
   CFWL_WidgetImpProperties prop;
   prop.m_pThemeProvider = m_pProperties->m_pThemeProvider;
   prop.m_dwStyles |= FWL_WGTSTYLE_Border | FWL_WGTSTYLE_VScroll;
-  if (m_pProperties->m_dwStyleExes & FWL_STYLEEXT_CMB_ListItemIconText) {
+  if (m_pProperties->m_dwStyleExes & FWL_STYLEEXT_CMB_ListItemIconText)
     prop.m_dwStyleExes |= FWL_STYLEEXT_LTB_Icon;
-  }
+
   prop.m_pDataProvider = m_pProperties->m_pDataProvider;
   m_pListBox.reset(IFWL_ListBox::CreateComboList(prop, m_pInterface));
   m_pListBox->Initialize();
@@ -513,13 +516,14 @@ FWL_ERR CFWL_ComboBoxImp::Initialize() {
     m_pEdit->Initialize();
     static_cast<CFWL_EditImp*>(m_pEdit->GetImpl())->SetOuter(m_pInterface);
   }
-  if (m_pEdit) {
+  if (m_pEdit)
     m_pEdit->SetParent(m_pInterface);
-  }
+
   SetStates(m_pProperties->m_dwStates);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ComboBoxImp::Finalize() {
+
+FWL_Error CFWL_ComboBoxImp::Finalize() {
   if (m_pEdit) {
     m_pEdit->Finalize();
   }
@@ -528,7 +532,7 @@ FWL_ERR CFWL_ComboBoxImp::Finalize() {
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_ComboBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
+FWL_Error CFWL_ComboBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   if (bAutoSize) {
     rect.Reset();
     FX_BOOL bIsDropDown = IsDropDownStyle();
@@ -544,16 +548,16 @@ FWL_ERR CFWL_ComboBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
     FX_FLOAT* pFWidth = static_cast<FX_FLOAT*>(
         GetThemeCapacity(CFWL_WidgetCapacity::ScrollBarWidth));
     if (!pFWidth)
-      return FWL_ERR_Indefinite;
+      return FWL_Error::Indefinite;
     rect.Inflate(0, 0, *pFWidth, 0);
     CFWL_WidgetImp::GetWidgetRect(rect, TRUE);
   } else {
     rect = m_pProperties->m_rtWidget;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ComboBoxImp::ModifyStylesEx(uint32_t dwStylesExAdded,
-                                         uint32_t dwStylesExRemoved) {
+FWL_Error CFWL_ComboBoxImp::ModifyStylesEx(uint32_t dwStylesExAdded,
+                                           uint32_t dwStylesExRemoved) {
   if (m_pWidgetMgr->IsFormDisabled()) {
     return DisForm_ModifyStylesEx(dwStylesExAdded, dwStylesExRemoved);
   }
@@ -570,12 +574,12 @@ FWL_ERR CFWL_ComboBoxImp::ModifyStylesEx(uint32_t dwStylesExAdded,
   }
   return CFWL_WidgetImp::ModifyStylesEx(dwStylesExAdded, dwStylesExRemoved);
 }
-FWL_ERR CFWL_ComboBoxImp::Update() {
+FWL_Error CFWL_ComboBoxImp::Update() {
   if (m_pWidgetMgr->IsFormDisabled()) {
     return DisForm_Update();
   }
   if (IsLocked()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   ReSetTheme();
   FX_BOOL bDropDown = IsDropDownStyle();
@@ -591,7 +595,7 @@ FWL_ERR CFWL_ComboBoxImp::Update() {
   m_fComboFormHandler =
       *static_cast<FX_FLOAT*>(m_pProperties->m_pThemeProvider->GetCapacity(
           &part, CFWL_WidgetCapacity::ComboFormHandler));
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FWL_WidgetHit CFWL_ComboBoxImp::HitTest(FX_FLOAT fx, FX_FLOAT fy) {
   if (m_pWidgetMgr->IsFormDisabled()) {
@@ -599,15 +603,15 @@ FWL_WidgetHit CFWL_ComboBoxImp::HitTest(FX_FLOAT fx, FX_FLOAT fy) {
   }
   return CFWL_WidgetImp::HitTest(fx, fy);
 }
-FWL_ERR CFWL_ComboBoxImp::DrawWidget(CFX_Graphics* pGraphics,
-                                     const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_ComboBoxImp::DrawWidget(CFX_Graphics* pGraphics,
+                                       const CFX_Matrix* pMatrix) {
   if (m_pWidgetMgr->IsFormDisabled()) {
     return DisForm_DrawWidget(pGraphics, pMatrix);
   }
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   IFWL_ThemeProvider* pTheme = m_pProperties->m_pThemeProvider;
   FX_BOOL bIsDropDown = IsDropDownStyle();
   if (HasBorder()) {
@@ -648,7 +652,7 @@ FWL_ERR CFWL_ComboBoxImp::DrawWidget(CFX_Graphics* pGraphics,
     pTheme->DrawBackground(&param);
     if (m_iCurSel >= 0) {
       if (!m_pListBox)
-        return FWL_ERR_Indefinite;
+        return FWL_Error::Indefinite;
       CFX_WideString wsText;
       IFWL_ComboBoxDP* pData =
           static_cast<IFWL_ComboBoxDP*>(m_pProperties->m_pDataProvider);
@@ -683,11 +687,12 @@ FWL_ERR CFWL_ComboBoxImp::DrawWidget(CFX_Graphics* pGraphics,
     param.m_rtPart = m_rtBtn;
     pTheme->DrawBackground(&param);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ComboBoxImp::SetThemeProvider(IFWL_ThemeProvider* pThemeProvider) {
+FWL_Error CFWL_ComboBoxImp::SetThemeProvider(
+    IFWL_ThemeProvider* pThemeProvider) {
   if (!pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   m_pProperties->m_pThemeProvider = pThemeProvider;
   if (m_pListBox && pThemeProvider->IsValidWidget(m_pListBox.get())) {
     m_pListBox->SetThemeProvider(pThemeProvider);
@@ -695,12 +700,12 @@ FWL_ERR CFWL_ComboBoxImp::SetThemeProvider(IFWL_ThemeProvider* pThemeProvider) {
   if (m_pEdit && pThemeProvider->IsValidWidget(m_pEdit.get())) {
     m_pEdit->SetThemeProvider(pThemeProvider);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 int32_t CFWL_ComboBoxImp::GetCurSel() {
   return m_iCurSel;
 }
-FWL_ERR CFWL_ComboBoxImp::SetCurSel(int32_t iSel) {
+FWL_Error CFWL_ComboBoxImp::SetCurSel(int32_t iSel) {
   int32_t iCount =
       static_cast<CFWL_ComboListImp*>(m_pListBox->GetImpl())->CountItems();
   FX_BOOL bClearSel = iSel < 0 || iSel >= iCount;
@@ -720,7 +725,7 @@ FWL_ERR CFWL_ComboBoxImp::SetCurSel(int32_t iSel) {
     m_pEdit->Update();
   }
   m_iCurSel = bClearSel ? -1 : iSel;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 
 void CFWL_ComboBoxImp::SetStates(uint32_t dwStates, FX_BOOL bSet) {
@@ -732,9 +737,9 @@ void CFWL_ComboBoxImp::SetStates(uint32_t dwStates, FX_BOOL bSet) {
   CFWL_WidgetImp::SetStates(dwStates, bSet);
 }
 
-FWL_ERR CFWL_ComboBoxImp::SetEditText(const CFX_WideString& wsText) {
+FWL_Error CFWL_ComboBoxImp::SetEditText(const CFX_WideString& wsText) {
   if (!m_pEdit)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   m_pEdit->SetText(wsText);
   return m_pEdit->Update();
 }
@@ -743,9 +748,9 @@ int32_t CFWL_ComboBoxImp::GetEditTextLength() const {
     return -1;
   return m_pEdit->GetTextLength();
 }
-FWL_ERR CFWL_ComboBoxImp::GetEditText(CFX_WideString& wsText,
-                                      int32_t nStart,
-                                      int32_t nCount) const {
+FWL_Error CFWL_ComboBoxImp::GetEditText(CFX_WideString& wsText,
+                                        int32_t nStart,
+                                        int32_t nCount) const {
   if (m_pEdit) {
     return m_pEdit->GetText(wsText, nStart, nCount);
   } else if (m_pListBox) {
@@ -754,14 +759,14 @@ FWL_ERR CFWL_ComboBoxImp::GetEditText(CFX_WideString& wsText,
     FWL_HLISTITEM hItem = pData->GetItem(m_pInterface, m_iCurSel);
     return m_pListBox->GetItemText(hItem, wsText);
   }
-  return FWL_ERR_Indefinite;
+  return FWL_Error::Indefinite;
 }
-FWL_ERR CFWL_ComboBoxImp::SetEditSelRange(int32_t nStart, int32_t nCount) {
+FWL_Error CFWL_ComboBoxImp::SetEditSelRange(int32_t nStart, int32_t nCount) {
   if (!m_pEdit)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   static_cast<CFWL_ComboEditImp*>(m_pEdit->GetImpl())->ClearSelected();
   m_pEdit->AddSelRange(nStart, nCount);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 int32_t CFWL_ComboBoxImp::GetEditSelRange(int32_t nIndex, int32_t& nStart) {
   if (!m_pEdit)
@@ -773,14 +778,14 @@ int32_t CFWL_ComboBoxImp::GetEditLimit() {
     return -1;
   return m_pEdit->GetLimit();
 }
-FWL_ERR CFWL_ComboBoxImp::SetEditLimit(int32_t nLimit) {
+FWL_Error CFWL_ComboBoxImp::SetEditLimit(int32_t nLimit) {
   if (!m_pEdit)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   return m_pEdit->SetLimit(nLimit);
 }
-FWL_ERR CFWL_ComboBoxImp::EditDoClipboard(int32_t iCmd) {
+FWL_Error CFWL_ComboBoxImp::EditDoClipboard(int32_t iCmd) {
   if (!m_pEdit)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   return m_pEdit->DoClipboard(iCmd);
 }
 FX_BOOL CFWL_ComboBoxImp::EditRedo(const CFX_ByteStringC& bsRecord) {
@@ -807,9 +812,9 @@ FX_BOOL CFWL_ComboBoxImp::AfterFocusShowDropList() {
   m_bNeedShowList = FALSE;
   return TRUE;
 }
-FX_ERR CFWL_ComboBoxImp::OpenDropDownList(FX_BOOL bActivate) {
+FWL_Error CFWL_ComboBoxImp::OpenDropDownList(FX_BOOL bActivate) {
   ShowDropList(bActivate);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FX_BOOL CFWL_ComboBoxImp::EditCanUndo() {
   return m_pEdit->CanUndo();
@@ -845,15 +850,15 @@ FX_BOOL CFWL_ComboBoxImp::EditPaste(const CFX_WideString& wsPaste) {
   return m_pEdit->Paste(wsPaste);
 }
 FX_BOOL CFWL_ComboBoxImp::EditSelectAll() {
-  return m_pEdit->AddSelRange(0) == FWL_ERR_Succeeded;
+  return m_pEdit->AddSelRange(0) == FWL_Error::Succeeded;
 }
 FX_BOOL CFWL_ComboBoxImp::EditDelete() {
-  return m_pEdit->ClearText() == FWL_ERR_Succeeded;
+  return m_pEdit->ClearText() == FWL_Error::Succeeded;
 }
 FX_BOOL CFWL_ComboBoxImp::EditDeSelect() {
-  return m_pEdit->ClearSelections() == FWL_ERR_Succeeded;
+  return m_pEdit->ClearSelections() == FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ComboBoxImp::GetBBox(CFX_RectF& rect) {
+FWL_Error CFWL_ComboBoxImp::GetBBox(CFX_RectF& rect) {
   if (m_pWidgetMgr->IsFormDisabled()) {
     return DisForm_GetBBox(rect);
   }
@@ -864,14 +869,14 @@ FWL_ERR CFWL_ComboBoxImp::GetBBox(CFX_RectF& rect) {
     rtList.Offset(rect.left, rect.top);
     rect.Union(rtList);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ComboBoxImp::EditModifyStylesEx(uint32_t dwStylesExAdded,
-                                             uint32_t dwStylesExRemoved) {
+FWL_Error CFWL_ComboBoxImp::EditModifyStylesEx(uint32_t dwStylesExAdded,
+                                               uint32_t dwStylesExRemoved) {
   if (m_pEdit != NULL) {
     return m_pEdit->ModifyStylesEx(dwStylesExAdded, dwStylesExRemoved);
   } else {
-    return FWL_ERR_Parameter_Invalid;
+    return FWL_Error::ParameterInvalid;
   }
 }
 FX_FLOAT CFWL_ComboBoxImp::GetListHeight() {
@@ -1129,11 +1134,13 @@ void CFWL_ComboBoxImp::ProcessSelChanged(FX_BOOL bLButtonUp) {
     Repaint(&m_rtClient);
   }
 }
+
 void CFWL_ComboBoxImp::InitProxyForm() {
   if (m_pForm)
     return;
   if (!m_pListBox)
     return;
+
   CFWL_WidgetImpProperties propForm;
   propForm.m_pOwner = m_pInterface;
   propForm.m_dwStyles = FWL_WGTSTYLE_Popup;
@@ -1146,18 +1153,21 @@ void CFWL_ComboBoxImp::InitProxyForm() {
   m_pListProxyDelegate = new CFWL_ComboProxyImpDelegate(m_pForm, this);
   m_pProxy->SetDelegate(m_pListProxyDelegate);
 }
-FWL_ERR CFWL_ComboBoxImp::DisForm_Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_WGTSTATE_Invisible;  // Ditto.
+
+FWL_Error CFWL_ComboBoxImp::DisForm_Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
+
   m_pDelegate = new CFWL_ComboBoxImpDelegate(this);
   DisForm_InitComboList();
   DisForm_InitComboEdit();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
+
 void CFWL_ComboBoxImp::DisForm_InitComboList() {
-  if (m_pListBox) {
+  if (m_pListBox)
     return;
-  }
+
   CFWL_WidgetImpProperties prop;
   prop.m_pParent = m_pInterface;
   prop.m_dwStyles = FWL_WGTSTYLE_Border | FWL_WGTSTYLE_VScroll;
@@ -1227,8 +1237,8 @@ void CFWL_ComboBoxImp::DisForm_ShowDropList(FX_BOOL bActivate) {
 FX_BOOL CFWL_ComboBoxImp::DisForm_IsDropListShowed() {
   return !(m_pListBox->GetStates() & FWL_WGTSTATE_Invisible);
 }
-FWL_ERR CFWL_ComboBoxImp::DisForm_ModifyStylesEx(uint32_t dwStylesExAdded,
-                                                 uint32_t dwStylesExRemoved) {
+FWL_Error CFWL_ComboBoxImp::DisForm_ModifyStylesEx(uint32_t dwStylesExAdded,
+                                                   uint32_t dwStylesExRemoved) {
   if (!m_pEdit) {
     DisForm_InitComboEdit();
   }
@@ -1243,16 +1253,16 @@ FWL_ERR CFWL_ComboBoxImp::DisForm_ModifyStylesEx(uint32_t dwStylesExAdded,
   }
   return CFWL_WidgetImp::ModifyStylesEx(dwStylesExAdded, dwStylesExRemoved);
 }
-FWL_ERR CFWL_ComboBoxImp::DisForm_Update() {
+FWL_Error CFWL_ComboBoxImp::DisForm_Update() {
   if (m_iLock) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   if (m_pEdit) {
     ReSetEditAlignment();
   }
   ReSetTheme();
   Layout();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FWL_WidgetHit CFWL_ComboBoxImp::DisForm_HitTest(FX_FLOAT fx, FX_FLOAT fy) {
   CFX_RectF rect;
@@ -1269,8 +1279,8 @@ FWL_WidgetHit CFWL_ComboBoxImp::DisForm_HitTest(FX_FLOAT fx, FX_FLOAT fy) {
   }
   return FWL_WidgetHit::Unknown;
 }
-FWL_ERR CFWL_ComboBoxImp::DisForm_DrawWidget(CFX_Graphics* pGraphics,
-                                             const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_ComboBoxImp::DisForm_DrawWidget(CFX_Graphics* pGraphics,
+                                               const CFX_Matrix* pMatrix) {
   IFWL_ThemeProvider* pTheme = m_pProperties->m_pThemeProvider;
   CFX_Matrix mtOrg;
   mtOrg.Set(1, 0, 0, 1, 0, 0);
@@ -1306,9 +1316,9 @@ FWL_ERR CFWL_ComboBoxImp::DisForm_DrawWidget(CFX_Graphics* pGraphics,
     mt.Concat(mtOrg);
     m_pListBox->DrawWidget(pGraphics, &mt);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ComboBoxImp::DisForm_GetBBox(CFX_RectF& rect) {
+FWL_Error CFWL_ComboBoxImp::DisForm_GetBBox(CFX_RectF& rect) {
   rect = m_pProperties->m_rtWidget;
   if (m_pListBox && DisForm_IsDropListShowed()) {
     CFX_RectF rtList;
@@ -1316,7 +1326,7 @@ FWL_ERR CFWL_ComboBoxImp::DisForm_GetBBox(CFX_RectF& rect) {
     rtList.Offset(rect.left, rect.top);
     rect.Union(rtList);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 void CFWL_ComboBoxImp::DisForm_Layout() {
   GetClientRect(m_rtClient);
@@ -1361,14 +1371,14 @@ void CFWL_ComboBoxImp::DisForm_Layout() {
 CFWL_ComboBoxImpDelegate::CFWL_ComboBoxImpDelegate(CFWL_ComboBoxImp* pOwner)
     : m_pOwner(pOwner) {}
 
-int32_t CFWL_ComboBoxImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
-  if (m_pOwner->m_pWidgetMgr->IsFormDisabled())
-    return DisForm_OnProcessMessage(pMessage);
-
+void CFWL_ComboBoxImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+  if (m_pOwner->m_pWidgetMgr->IsFormDisabled()) {
+    DisForm_OnProcessMessage(pMessage);
+    return;
+  }
   if (!pMessage)
-    return 0;
+    return;
 
-  FX_BOOL iRet = 1;
   switch (pMessage->GetClassID()) {
     case CFWL_MessageType::SetFocus: {
       OnFocusChanged(pMessage, TRUE);
@@ -1407,16 +1417,14 @@ int32_t CFWL_ComboBoxImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
       break;
     }
     default: {
-      iRet = 0;
       break;
     }
   }
 
   CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
-  return iRet;
 }
 
-FWL_ERR CFWL_ComboBoxImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
+void CFWL_ComboBoxImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
   CFWL_EventType dwFlag = pEvent->GetClassID();
   if (dwFlag == CFWL_EventType::DrawItem) {
     CFWL_EvtLtbDrawItem* pDrawItemEvent =
@@ -1444,13 +1452,13 @@ FWL_ERR CFWL_ComboBoxImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
     pTemp.nChangeType = pTextChangedEvent->nChangeType;
     m_pOwner->DispatchEvent(&pTemp);
   }
-  return FWL_ERR_Succeeded;
 }
 
-FWL_ERR CFWL_ComboBoxImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                               const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+void CFWL_ComboBoxImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                            const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
+
 void CFWL_ComboBoxImpDelegate::OnFocusChanged(CFWL_Message* pMsg,
                                               FX_BOOL bSet) {
   IFWL_Widget* pDstTarget = pMsg->m_pDstTarget;
@@ -1594,10 +1602,10 @@ void CFWL_ComboBoxImpDelegate::DoSubCtrlKey(CFWL_MsgKey* pMsg) {
     pDelegate->OnProcessMessage(pMsg);
   }
 }
-int32_t CFWL_ComboBoxImpDelegate::DisForm_OnProcessMessage(
+void CFWL_ComboBoxImpDelegate::DisForm_OnProcessMessage(
     CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
 
   FX_BOOL backDefault = TRUE;
   switch (pMessage->GetClassID()) {
@@ -1652,9 +1660,8 @@ int32_t CFWL_ComboBoxImpDelegate::DisForm_OnProcessMessage(
     default:
       break;
   }
-  if (!backDefault)
-    return 1;
-  return CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
+  if (backDefault)
+    CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
 }
 
 void CFWL_ComboBoxImpDelegate::DisForm_OnLButtonDown(CFWL_MsgMouse* pMsg) {
@@ -1750,9 +1757,9 @@ CFWL_ComboProxyImpDelegate::CFWL_ComboProxyImpDelegate(
       m_pForm(pForm),
       m_pComboBox(pComboBox) {}
 
-int32_t CFWL_ComboProxyImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+void CFWL_ComboProxyImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
 
   switch (pMessage->GetClassID()) {
     case CFWL_MessageType::Mouse: {
@@ -1790,14 +1797,14 @@ int32_t CFWL_ComboProxyImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
     default:
       break;
   }
-  return CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
+  CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
 }
 
-FWL_ERR CFWL_ComboProxyImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                                 const CFX_Matrix* pMatrix) {
+void CFWL_ComboProxyImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                              const CFX_Matrix* pMatrix) {
   m_pComboBox->DrawStretchHandler(pGraphics, pMatrix);
-  return FWL_ERR_Succeeded;
 }
+
 void CFWL_ComboProxyImpDelegate::OnLButtonDown(CFWL_MsgMouse* pMsg) {
   IFWL_App* pApp = m_pForm->GetOwnerApp();
   if (!pApp)
diff --git a/xfa/fwl/basewidget/fwl_comboboximp.h b/xfa/fwl/basewidget/fwl_comboboximp.h
index 202ba7cae2..6fa097a4c0 100644
--- a/xfa/fwl/basewidget/fwl_comboboximp.h
+++ b/xfa/fwl/basewidget/fwl_comboboximp.h
@@ -44,7 +44,7 @@ class CFWL_ComboEditImp : public CFWL_EditImp {
 class CFWL_ComboEditImpDelegate : public CFWL_EditImpDelegate {
  public:
   CFWL_ComboEditImpDelegate(CFWL_ComboEditImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
 
  protected:
   CFWL_ComboEditImp* m_pOwner;
@@ -53,8 +53,8 @@ class CFWL_ComboListImp : public CFWL_ListBoxImp {
  public:
   CFWL_ComboListImp(const CFWL_WidgetImpProperties& properties,
                     IFWL_Widget* pOuter);
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
   int32_t MatchItem(const CFX_WideString& wsMatch);
   void ChangeSelected(int32_t iSel);
   int32_t CountItems();
@@ -68,7 +68,7 @@ class CFWL_ComboListImp : public CFWL_ListBoxImp {
 class CFWL_ComboListImpDelegate : public CFWL_ListBoxImpDelegate {
  public:
   CFWL_ComboListImpDelegate(CFWL_ComboListImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
 
  protected:
   void OnDropListFocusChanged(CFWL_Message* pMsg, FX_BOOL bSet = TRUE);
@@ -84,36 +84,36 @@ class CFWL_ComboBoxImp : public CFWL_WidgetImp {
   CFWL_ComboBoxImp(const CFWL_WidgetImpProperties& properties,
                    IFWL_Widget* pOuter);
   virtual ~CFWL_ComboBoxImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  virtual FWL_ERR ModifyStylesEx(uint32_t dwStylesExAdded,
-                                 uint32_t dwStylesExRemoved);
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error ModifyStylesEx(uint32_t dwStylesExAdded,
+                                   uint32_t dwStylesExRemoved);
   virtual void SetStates(uint32_t dwStates, FX_BOOL bSet = TRUE);
-  virtual FWL_ERR Update();
+  virtual FWL_Error Update();
   virtual FWL_WidgetHit HitTest(FX_FLOAT fx, FX_FLOAT fy);
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
-  virtual FWL_ERR SetThemeProvider(IFWL_ThemeProvider* pThemeProvider);
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error SetThemeProvider(IFWL_ThemeProvider* pThemeProvider);
   virtual int32_t GetCurSel();
-  virtual FWL_ERR SetCurSel(int32_t iSel);
-  virtual FWL_ERR SetEditText(const CFX_WideString& wsText);
+  virtual FWL_Error SetCurSel(int32_t iSel);
+  virtual FWL_Error SetEditText(const CFX_WideString& wsText);
   virtual int32_t GetEditTextLength() const;
-  virtual FWL_ERR GetEditText(CFX_WideString& wsText,
-                              int32_t nStart = 0,
-                              int32_t nCount = -1) const;
-  virtual FWL_ERR SetEditSelRange(int32_t nStart, int32_t nCount = -1);
+  virtual FWL_Error GetEditText(CFX_WideString& wsText,
+                                int32_t nStart = 0,
+                                int32_t nCount = -1) const;
+  virtual FWL_Error SetEditSelRange(int32_t nStart, int32_t nCount = -1);
   virtual int32_t GetEditSelRange(int32_t nIndex, int32_t& nStart);
   virtual int32_t GetEditLimit();
-  virtual FWL_ERR SetEditLimit(int32_t nLimit);
-  virtual FWL_ERR EditDoClipboard(int32_t iCmd);
+  virtual FWL_Error SetEditLimit(int32_t nLimit);
+  virtual FWL_Error EditDoClipboard(int32_t iCmd);
   virtual FX_BOOL EditRedo(const CFX_ByteStringC& bsRecord);
   virtual FX_BOOL EditUndo(const CFX_ByteStringC& bsRecord);
   virtual IFWL_ListBox* GetListBoxt();
   virtual FX_BOOL AfterFocusShowDropList();
-  virtual FX_ERR OpenDropDownList(FX_BOOL bActivate);
+  virtual FWL_Error OpenDropDownList(FX_BOOL bActivate);
   virtual FX_BOOL EditCanUndo();
   virtual FX_BOOL EditCanRedo();
   virtual FX_BOOL EditUndo();
@@ -127,9 +127,9 @@ class CFWL_ComboBoxImp : public CFWL_WidgetImp {
   virtual FX_BOOL EditSelectAll();
   virtual FX_BOOL EditDelete();
   virtual FX_BOOL EditDeSelect();
-  virtual FWL_ERR GetBBox(CFX_RectF& rect);
-  virtual FWL_ERR EditModifyStylesEx(uint32_t dwStylesExAdded,
-                                     uint32_t dwStylesExRemoved);
+  virtual FWL_Error GetBBox(CFX_RectF& rect);
+  virtual FWL_Error EditModifyStylesEx(uint32_t dwStylesExAdded,
+                                       uint32_t dwStylesExRemoved);
 
  protected:
   void DrawStretchHandler(CFX_Graphics* pGraphics, const CFX_Matrix* pMatrix);
@@ -145,18 +145,18 @@ class CFWL_ComboBoxImp : public CFWL_WidgetImp {
   void ReSetListItemAlignment();
   void ProcessSelChanged(FX_BOOL bLButtonUp);
   void InitProxyForm();
-  FWL_ERR DisForm_Initialize();
+  FWL_Error DisForm_Initialize();
   void DisForm_InitComboList();
   void DisForm_InitComboEdit();
   void DisForm_ShowDropList(FX_BOOL bActivate);
   FX_BOOL DisForm_IsDropListShowed();
-  FWL_ERR DisForm_ModifyStylesEx(uint32_t dwStylesExAdded,
-                                 uint32_t dwStylesExRemoved);
-  FWL_ERR DisForm_Update();
+  FWL_Error DisForm_ModifyStylesEx(uint32_t dwStylesExAdded,
+                                   uint32_t dwStylesExRemoved);
+  FWL_Error DisForm_Update();
   FWL_WidgetHit DisForm_HitTest(FX_FLOAT fx, FX_FLOAT fy);
-  FWL_ERR DisForm_DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
-  FWL_ERR DisForm_GetBBox(CFX_RectF& rect);
+  FWL_Error DisForm_DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
+  FWL_Error DisForm_GetBBox(CFX_RectF& rect);
   void DisForm_Layout();
 
   CFX_RectF m_rtClient;
@@ -188,10 +188,10 @@ class CFWL_ComboBoxImp : public CFWL_WidgetImp {
 class CFWL_ComboBoxImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_ComboBoxImpDelegate(CFWL_ComboBoxImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnProcessEvent(CFWL_Event* pEvent) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessEvent(CFWL_Event* pEvent) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void OnFocusChanged(CFWL_Message* pMsg, FX_BOOL bSet = TRUE);
@@ -203,7 +203,7 @@ class CFWL_ComboBoxImpDelegate : public CFWL_WidgetImpDelegate {
   void DoSubCtrlKey(CFWL_MsgKey* pMsg);
 
  protected:
-  int32_t DisForm_OnProcessMessage(CFWL_Message* pMessage);
+  void DisForm_OnProcessMessage(CFWL_Message* pMessage);
   void DisForm_OnLButtonDown(CFWL_MsgMouse* pMsg);
   void DisForm_OnFocusChanged(CFWL_Message* pMsg, FX_BOOL bSet = TRUE);
   void DisForm_OnKey(CFWL_MsgKey* pMsg);
@@ -216,9 +216,9 @@ class CFWL_ComboBoxImpDelegate : public CFWL_WidgetImpDelegate {
 class CFWL_ComboProxyImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_ComboProxyImpDelegate(IFWL_Form* pForm, CFWL_ComboBoxImp* pComboBox);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
   void Reset() { m_bLButtonUpSelf = FALSE; }
 
  protected:
diff --git a/xfa/fwl/basewidget/fwl_datetimepickerimp.cpp b/xfa/fwl/basewidget/fwl_datetimepickerimp.cpp
index 7cefdc3477..e65b5bfb3d 100644
--- a/xfa/fwl/basewidget/fwl_datetimepickerimp.cpp
+++ b/xfa/fwl/basewidget/fwl_datetimepickerimp.cpp
@@ -83,24 +83,24 @@ int32_t IFWL_DateTimePicker::GetSelRange(int32_t nIndex, int32_t& nStart) {
       ->GetDataTimeEdit()
       ->GetSelRange(nIndex, nStart);
 }
-FWL_ERR IFWL_DateTimePicker::GetCurSel(int32_t& iYear,
-                                       int32_t& iMonth,
-                                       int32_t& iDay) {
+FWL_Error IFWL_DateTimePicker::GetCurSel(int32_t& iYear,
+                                         int32_t& iMonth,
+                                         int32_t& iDay) {
   return static_cast<CFWL_DateTimePickerImp*>(GetImpl())
       ->GetCurSel(iYear, iMonth, iDay);
 }
-FWL_ERR IFWL_DateTimePicker::SetCurSel(int32_t iYear,
-                                       int32_t iMonth,
-                                       int32_t iDay) {
+FWL_Error IFWL_DateTimePicker::SetCurSel(int32_t iYear,
+                                         int32_t iMonth,
+                                         int32_t iDay) {
   return static_cast<CFWL_DateTimePickerImp*>(GetImpl())
       ->SetCurSel(iYear, iMonth, iDay);
 }
-FWL_ERR IFWL_DateTimePicker::SetEditText(const CFX_WideString& wsText) {
+FWL_Error IFWL_DateTimePicker::SetEditText(const CFX_WideString& wsText) {
   return static_cast<CFWL_DateTimePickerImp*>(GetImpl())->SetEditText(wsText);
 }
-FWL_ERR IFWL_DateTimePicker::GetEditText(CFX_WideString& wsText,
-                                         int32_t nStart,
-                                         int32_t nCount) const {
+FWL_Error IFWL_DateTimePicker::GetEditText(CFX_WideString& wsText,
+                                           int32_t nStart,
+                                           int32_t nCount) const {
   return static_cast<CFWL_DateTimePickerImp*>(GetImpl())
       ->GetEditText(wsText, nStart, nCount);
 }
@@ -143,27 +143,27 @@ FX_BOOL IFWL_DateTimePicker::Delete() {
 FX_BOOL IFWL_DateTimePicker::DeSelect() {
   return static_cast<CFWL_DateTimePickerImp*>(GetImpl())->DeSelect();
 }
-FWL_ERR IFWL_DateTimePicker::GetBBox(CFX_RectF& rect) {
+FWL_Error IFWL_DateTimePicker::GetBBox(CFX_RectF& rect) {
   return static_cast<CFWL_DateTimePickerImp*>(GetImpl())->GetBBox(rect);
 }
-FWL_ERR IFWL_DateTimePicker::SetEditLimit(int32_t nLimit) {
+FWL_Error IFWL_DateTimePicker::SetEditLimit(int32_t nLimit) {
   return static_cast<CFWL_DateTimePickerImp*>(GetImpl())->SetEditLimit(nLimit);
 }
-FWL_ERR IFWL_DateTimePicker::ModifyEditStylesEx(uint32_t dwStylesExAdded,
-                                                uint32_t dwStylesExRemoved) {
+FWL_Error IFWL_DateTimePicker::ModifyEditStylesEx(uint32_t dwStylesExAdded,
+                                                  uint32_t dwStylesExRemoved) {
   return static_cast<CFWL_DateTimePickerImp*>(GetImpl())
       ->ModifyEditStylesEx(dwStylesExAdded, dwStylesExRemoved);
 }
 CFWL_DateTimeEdit::CFWL_DateTimeEdit(const CFWL_WidgetImpProperties& properties,
                                      IFWL_Widget* pOuter)
     : CFWL_EditImp(properties, pOuter) {}
-FWL_ERR CFWL_DateTimeEdit::Initialize() {
+FWL_Error CFWL_DateTimeEdit::Initialize() {
   m_pDelegate = new CFWL_DateTimeEditImpDelegate(this);
-  if (CFWL_EditImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
-  return FWL_ERR_Succeeded;
+  if (CFWL_EditImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimeEdit::Finalize() {
+FWL_Error CFWL_DateTimeEdit::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_EditImp::Finalize();
@@ -173,9 +173,11 @@ CFWL_DateTimeEditImpDelegate::CFWL_DateTimeEditImpDelegate(
     CFWL_DateTimeEdit* pOwner)
     : CFWL_EditImpDelegate(pOwner), m_pOwner(pOwner) {}
 
-int32_t CFWL_DateTimeEditImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
-  if (m_pOwner->m_pWidgetMgr->IsFormDisabled())
-    return DisForm_OnProcessMessage(pMessage);
+void CFWL_DateTimeEditImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+  if (m_pOwner->m_pWidgetMgr->IsFormDisabled()) {
+    DisForm_OnProcessMessage(pMessage);
+    return;
+  }
 
   CFWL_MessageType dwHashCode = pMessage->GetClassID();
   if (dwHashCode == CFWL_MessageType::SetFocus ||
@@ -184,10 +186,9 @@ int32_t CFWL_DateTimeEditImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
     IFWL_WidgetDelegate* pDelegate = pOuter->SetDelegate(NULL);
     pDelegate->OnProcessMessage(pMessage);
   }
-  return 1;
 }
 
-int32_t CFWL_DateTimeEditImpDelegate::DisForm_OnProcessMessage(
+void CFWL_DateTimeEditImpDelegate::DisForm_OnProcessMessage(
     CFWL_Message* pMessage) {
   CFWL_MessageType dwHashCode = pMessage->GetClassID();
   if (m_pOwner->m_pWidgetMgr->IsFormDisabled()) {
@@ -208,25 +209,23 @@ int32_t CFWL_DateTimeEditImpDelegate::DisForm_OnProcessMessage(
           pDateTime->Repaint(&rtInvalidate);
         }
       }
-    } else if (dwHashCode == CFWL_MessageType::Key) {
-      return CFWL_EditImpDelegate::OnProcessMessage(pMessage);
     }
   }
-  return CFWL_EditImpDelegate::OnProcessMessage(pMessage);
+  CFWL_EditImpDelegate::OnProcessMessage(pMessage);
 }
 
 CFWL_DateTimeCalendar::CFWL_DateTimeCalendar(
     const CFWL_WidgetImpProperties& properties,
     IFWL_Widget* pOuter)
     : CFWL_MonthCalendarImp(properties, pOuter) {}
-FWL_ERR CFWL_DateTimeCalendar::Initialize() {
-  if (CFWL_MonthCalendarImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_DateTimeCalendar::Initialize() {
+  if (CFWL_MonthCalendarImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   delete m_pDelegate;
   m_pDelegate = new CFWL_DateTimeCalendarImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimeCalendar::Finalize() {
+FWL_Error CFWL_DateTimeCalendar::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_MonthCalendarImp::Finalize();
@@ -238,25 +237,25 @@ CFWL_DateTimeCalendarImpDelegate::CFWL_DateTimeCalendarImpDelegate(
   m_bFlag = FALSE;
 }
 
-int32_t CFWL_DateTimeCalendarImpDelegate::OnProcessMessage(
+void CFWL_DateTimeCalendarImpDelegate::OnProcessMessage(
     CFWL_Message* pMessage) {
   CFWL_MessageType dwCode = pMessage->GetClassID();
   if (dwCode == CFWL_MessageType::SetFocus ||
       dwCode == CFWL_MessageType::KillFocus) {
     IFWL_Widget* pOuter = m_pOwner->GetOuter();
     IFWL_WidgetDelegate* pDelegate = pOuter->SetDelegate(NULL);
-    return pDelegate->OnProcessMessage(pMessage);
-  } else if (dwCode == CFWL_MessageType::Mouse) {
+    pDelegate->OnProcessMessage(pMessage);
+    return;
+  }
+  if (dwCode == CFWL_MessageType::Mouse) {
     CFWL_MsgMouse* pMsg = static_cast<CFWL_MsgMouse*>(pMessage);
-    if (pMsg->m_dwCmd == FWL_MouseCommand::LeftButtonDown) {
+    if (pMsg->m_dwCmd == FWL_MouseCommand::LeftButtonDown)
       OnLButtonDownEx(pMsg);
-      return 1;
-    } else if (pMsg->m_dwCmd == FWL_MouseCommand::LeftButtonUp) {
+    else if (pMsg->m_dwCmd == FWL_MouseCommand::LeftButtonUp)
       OnLButtonUpEx(pMsg);
-      return 1;
-    }
+    return;
   }
-  return CFWL_MonthCalendarImpDelegate::OnProcessMessage(pMessage);
+  CFWL_MonthCalendarImpDelegate::OnProcessMessage(pMessage);
 }
 
 void CFWL_DateTimeCalendarImpDelegate::OnLButtonDownEx(CFWL_MsgMouse* pMsg) {
@@ -375,16 +374,16 @@ void CFWL_DateTimeCalendarImpDelegate::OnMouseMoveEx(CFWL_MsgMouse* pMsg) {
   }
 }
 
-int32_t CFWL_DateTimeCalendarImpDelegate::DisForm_OnProcessMessage(
+void CFWL_DateTimeCalendarImpDelegate::DisForm_OnProcessMessage(
     CFWL_Message* pMessage) {
   if (pMessage->GetClassID() == CFWL_MessageType::Mouse) {
     CFWL_MsgMouse* pMsg = static_cast<CFWL_MsgMouse*>(pMessage);
     if (pMsg->m_dwCmd == FWL_MouseCommand::LeftButtonUp) {
       DisForm_OnLButtonUpEx(pMsg);
-      return 1;
+      return;
     }
   }
-  return CFWL_MonthCalendarImpDelegate::OnProcessMessage(pMessage);
+  CFWL_MonthCalendarImpDelegate::OnProcessMessage(pMessage);
 }
 
 void CFWL_DateTimeCalendarImpDelegate::DisForm_OnLButtonUpEx(
@@ -437,16 +436,16 @@ CFWL_DateTimePickerImp::CFWL_DateTimePickerImp(
   m_rtBtn.Set(0, 0, 0, 0);
 }
 CFWL_DateTimePickerImp::~CFWL_DateTimePickerImp() {}
-FWL_ERR CFWL_DateTimePickerImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_DateTimePickerImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_DateTimePicker;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_DateTimePickerImp::GetClassID() const {
   return FWL_CLASSHASH_DateTimePicker;
 }
-FWL_ERR CFWL_DateTimePickerImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_DateTimePickerImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_DateTimePickerImpDelegate(this);
   m_pProperties->m_dwStyleExes = FWL_STYLEEXT_DTP_ShortDateFormat;
   CFWL_WidgetImpProperties propMonth;
@@ -468,9 +467,9 @@ FWL_ERR CFWL_DateTimePickerImp::Initialize() {
   m_pEdit->Initialize();
   RegisterEventTarget(m_pMonthCal.get());
   RegisterEventTarget(m_pEdit.get());
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::Finalize() {
+FWL_Error CFWL_DateTimePickerImp::Finalize() {
   if (m_pEdit) {
     m_pEdit->Finalize();
   }
@@ -485,8 +484,8 @@ FWL_ERR CFWL_DateTimePickerImp::Finalize() {
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_DateTimePickerImp::GetWidgetRect(CFX_RectF& rect,
-                                              FX_BOOL bAutoSize) {
+FWL_Error CFWL_DateTimePickerImp::GetWidgetRect(CFX_RectF& rect,
+                                                FX_BOOL bAutoSize) {
   if (m_pWidgetMgr->IsFormDisabled()) {
     return DisForm_GetWidgetRect(rect, bAutoSize);
   }
@@ -496,14 +495,14 @@ FWL_ERR CFWL_DateTimePickerImp::GetWidgetRect(CFX_RectF& rect,
   } else {
     rect = m_pProperties->m_rtWidget;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::Update() {
+FWL_Error CFWL_DateTimePickerImp::Update() {
   if (m_pWidgetMgr->IsFormDisabled()) {
     return DisForm_Update();
   }
   if (m_iLock) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   if (!m_pProperties->m_pThemeProvider) {
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
@@ -513,7 +512,7 @@ FWL_ERR CFWL_DateTimePickerImp::Update() {
   FX_FLOAT* pFWidth = static_cast<FX_FLOAT*>(
       GetThemeCapacity(CFWL_WidgetCapacity::ScrollBarWidth));
   if (!pFWidth)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   FX_FLOAT fBtn = *pFWidth;
   m_rtBtn.Set(m_rtClient.right() - fBtn, m_rtClient.top, fBtn - 1,
               m_rtClient.height - 1);
@@ -539,7 +538,7 @@ FWL_ERR CFWL_DateTimePickerImp::Update() {
               rtMonthCal.width, rtMonthCal.height);
   m_pMonthCal->SetWidgetRect(rtPopUp);
   m_pMonthCal->Update();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FWL_WidgetHit CFWL_DateTimePickerImp::HitTest(FX_FLOAT fx, FX_FLOAT fy) {
   if (m_pWidgetMgr->IsFormDisabled())
@@ -554,12 +553,12 @@ FWL_WidgetHit CFWL_DateTimePickerImp::HitTest(FX_FLOAT fx, FX_FLOAT fy) {
   }
   return FWL_WidgetHit::Unknown;
 }
-FWL_ERR CFWL_DateTimePickerImp::DrawWidget(CFX_Graphics* pGraphics,
-                                           const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_DateTimePickerImp::DrawWidget(CFX_Graphics* pGraphics,
+                                             const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   IFWL_ThemeProvider* pTheme = m_pProperties->m_pThemeProvider;
   if (HasBorder()) {
     DrawBorder(pGraphics, CFWL_Part::Border, pTheme, pMatrix);
@@ -573,53 +572,56 @@ FWL_ERR CFWL_DateTimePickerImp::DrawWidget(CFX_Graphics* pGraphics,
   if (m_pWidgetMgr->IsFormDisabled()) {
     return DisForm_DrawWidget(pGraphics, pMatrix);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::SetThemeProvider(IFWL_ThemeProvider* pTP) {
+FWL_Error CFWL_DateTimePickerImp::SetThemeProvider(IFWL_ThemeProvider* pTP) {
   m_pProperties->m_pThemeProvider = pTP;
   m_pMonthCal->SetThemeProvider(pTP);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::GetCurSel(int32_t& iYear,
-                                          int32_t& iMonth,
-                                          int32_t& iDay) {
+FWL_Error CFWL_DateTimePickerImp::GetCurSel(int32_t& iYear,
+                                            int32_t& iMonth,
+                                            int32_t& iDay) {
   iYear = m_iYear;
   iMonth = m_iMonth;
   iDay = m_iDay;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::SetCurSel(int32_t iYear,
-                                          int32_t iMonth,
-                                          int32_t iDay) {
+FWL_Error CFWL_DateTimePickerImp::SetCurSel(int32_t iYear,
+                                            int32_t iMonth,
+                                            int32_t iDay) {
   if (iYear <= 0 || iYear >= 3000)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (iMonth <= 0 || iMonth >= 13)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (iDay <= 0 || iDay >= 32)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   m_iYear = iYear;
   m_iMonth = iMonth;
   m_iDay = iDay;
   m_pMonthCal->SetSelect(iYear, iMonth, iDay);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::SetEditText(const CFX_WideString& wsText) {
+
+FWL_Error CFWL_DateTimePickerImp::SetEditText(const CFX_WideString& wsText) {
   if (!m_pEdit)
-    return FWL_ERR_Indefinite;
-  int32_t iRet = m_pEdit->SetText(wsText);
+    return FWL_Error::Indefinite;
+
+  FWL_Error iRet = m_pEdit->SetText(wsText);
   Repaint(&m_rtClient);
   CFWL_Event_DtpEditChanged ev;
   ev.m_wsText = wsText;
   DispatchEvent(&ev);
   return iRet;
 }
-FWL_ERR CFWL_DateTimePickerImp::GetEditText(CFX_WideString& wsText,
-                                            int32_t nStart,
-                                            int32_t nCount) const {
+
+FWL_Error CFWL_DateTimePickerImp::GetEditText(CFX_WideString& wsText,
+                                              int32_t nStart,
+                                              int32_t nCount) const {
   if (m_pEdit) {
     return m_pEdit->GetText(wsText, nStart, nCount);
   }
-  return FWL_ERR_Indefinite;
+  return FWL_Error::Indefinite;
 }
 FX_BOOL CFWL_DateTimePickerImp::CanUndo() {
   return m_pEdit->CanUndo();
@@ -657,15 +659,15 @@ FX_BOOL CFWL_DateTimePickerImp::Paste(const CFX_WideString& wsPaste) {
   return m_pEdit->Paste(wsPaste);
 }
 FX_BOOL CFWL_DateTimePickerImp::SelectAll() {
-  return m_pEdit->AddSelRange(0) == FWL_ERR_Succeeded;
+  return m_pEdit->AddSelRange(0) == FWL_Error::Succeeded;
 }
 FX_BOOL CFWL_DateTimePickerImp::Delete() {
-  return m_pEdit->ClearText() == FWL_ERR_Succeeded;
+  return m_pEdit->ClearText() == FWL_Error::Succeeded;
 }
 FX_BOOL CFWL_DateTimePickerImp::DeSelect() {
-  return m_pEdit->ClearSelections() == FWL_ERR_Succeeded;
+  return m_pEdit->ClearSelections() == FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::GetBBox(CFX_RectF& rect) {
+FWL_Error CFWL_DateTimePickerImp::GetBBox(CFX_RectF& rect) {
   if (m_pWidgetMgr->IsFormDisabled()) {
     return DisForm_GetBBox(rect);
   }
@@ -677,13 +679,14 @@ FWL_ERR CFWL_DateTimePickerImp::GetBBox(CFX_RectF& rect) {
                    m_pProperties->m_rtWidget.top);
     rect.Union(rtMonth);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::SetEditLimit(int32_t nLimit) {
+FWL_Error CFWL_DateTimePickerImp::SetEditLimit(int32_t nLimit) {
   return m_pEdit->SetLimit(nLimit);
 }
-FWL_ERR CFWL_DateTimePickerImp::ModifyEditStylesEx(uint32_t dwStylesExAdded,
-                                                   uint32_t dwStylesExRemoved) {
+FWL_Error CFWL_DateTimePickerImp::ModifyEditStylesEx(
+    uint32_t dwStylesExAdded,
+    uint32_t dwStylesExRemoved) {
   return m_pEdit->ModifyStylesEx(dwStylesExAdded, dwStylesExRemoved);
 }
 void CFWL_DateTimePickerImp::DrawDropDownButton(CFX_Graphics* pGraphics,
@@ -830,13 +833,13 @@ void CFWL_DateTimePickerImp::InitProxyForm() {
 IFWL_DateTimeEdit* CFWL_DateTimePickerImp::GetDataTimeEdit() {
   return m_pEdit.get();
 }
-FWL_ERR CFWL_DateTimePickerImp::DisForm_Initialize() {
+FWL_Error CFWL_DateTimePickerImp::DisForm_Initialize() {
   m_pProperties->m_dwStyleExes = FWL_STYLEEXT_DTP_ShortDateFormat;
   DisForm_InitDateTimeCalendar();
   DisForm_InitDateTimeEdit();
   RegisterEventTarget(m_pMonthCal.get());
   RegisterEventTarget(m_pEdit.get());
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 void CFWL_DateTimePickerImp::DisForm_InitDateTimeCalendar() {
   if (m_pMonthCal) {
@@ -932,21 +935,21 @@ FX_BOOL CFWL_DateTimePickerImp::DisForm_IsNeedShowButton() {
                    m_pEdit->GetStates() & FWL_WGTSTATE_Focused;
   return bFocus;
 }
-FWL_ERR CFWL_DateTimePickerImp::DisForm_Update() {
-  if (m_iLock) {
-    return FWL_ERR_Indefinite;
-  }
-  if (!m_pProperties->m_pThemeProvider) {
+
+FWL_Error CFWL_DateTimePickerImp::DisForm_Update() {
+  if (m_iLock)
+    return FWL_Error::Indefinite;
+  if (!m_pProperties->m_pThemeProvider)
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
-  }
+
   m_pEdit->SetThemeProvider(m_pProperties->m_pThemeProvider);
   GetClientRect(m_rtClient);
   m_pEdit->SetWidgetRect(m_rtClient);
   ReSetEditAlignment();
   m_pEdit->Update();
-  if (m_pMonthCal->GetThemeProvider() == NULL) {
+  if (!m_pMonthCal->GetThemeProvider())
     m_pMonthCal->SetThemeProvider(m_pProperties->m_pThemeProvider);
-  }
+
   if (m_pProperties->m_pDataProvider) {
     IFWL_DateTimePickerDP* pData =
         static_cast<IFWL_DateTimePickerDP*>(m_pProperties->m_pDataProvider);
@@ -956,7 +959,8 @@ FWL_ERR CFWL_DateTimePickerImp::DisForm_Update() {
   FX_FLOAT* pWidth = static_cast<FX_FLOAT*>(
       GetThemeCapacity(CFWL_WidgetCapacity::ScrollBarWidth));
   if (!pWidth)
-    return 0;
+    return FWL_Error::Succeeded;
+
   m_fBtn = *pWidth;
   CFX_RectF rtMonthCal;
   m_pMonthCal->GetWidgetRect(rtMonthCal, TRUE);
@@ -965,17 +969,18 @@ FWL_ERR CFWL_DateTimePickerImp::DisForm_Update() {
               rtMonthCal.width, rtMonthCal.height);
   m_pMonthCal->SetWidgetRect(rtPopUp);
   m_pMonthCal->Update();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::DisForm_GetWidgetRect(CFX_RectF& rect,
-                                                      FX_BOOL bAutoSize) {
+
+FWL_Error CFWL_DateTimePickerImp::DisForm_GetWidgetRect(CFX_RectF& rect,
+                                                        FX_BOOL bAutoSize) {
   rect = m_pProperties->m_rtWidget;
   if (DisForm_IsNeedShowButton()) {
     rect.width += m_fBtn;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::DisForm_GetBBox(CFX_RectF& rect) {
+FWL_Error CFWL_DateTimePickerImp::DisForm_GetBBox(CFX_RectF& rect) {
   rect = m_pProperties->m_rtWidget;
   if (DisForm_IsNeedShowButton()) {
     rect.width += m_fBtn;
@@ -987,12 +992,13 @@ FWL_ERR CFWL_DateTimePickerImp::DisForm_GetBBox(CFX_RectF& rect) {
                    m_pProperties->m_rtWidget.top);
     rect.Union(rtMonth);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_DateTimePickerImp::DisForm_DrawWidget(CFX_Graphics* pGraphics,
-                                                   const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_DateTimePickerImp::DisForm_DrawWidget(
+    CFX_Graphics* pGraphics,
+    const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (m_pEdit) {
     CFX_RectF rtEdit;
     m_pEdit->GetWidgetRect(rtEdit);
@@ -1013,17 +1019,16 @@ FWL_ERR CFWL_DateTimePickerImp::DisForm_DrawWidget(CFX_Graphics* pGraphics,
     }
     m_pMonthCal->DrawWidget(pGraphics, &mt);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 
 CFWL_DateTimePickerImpDelegate::CFWL_DateTimePickerImpDelegate(
     CFWL_DateTimePickerImp* pOwner)
     : m_pOwner(pOwner) {}
 
-int32_t CFWL_DateTimePickerImpDelegate::OnProcessMessage(
-    CFWL_Message* pMessage) {
+void CFWL_DateTimePickerImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
 
   switch (pMessage->GetClassID()) {
     case CFWL_MessageType::SetFocus: {
@@ -1061,7 +1066,8 @@ int32_t CFWL_DateTimePickerImpDelegate::OnProcessMessage(
     case CFWL_MessageType::Key: {
       if (m_pOwner->m_pEdit->GetStates() & FWL_WGTSTATE_Focused) {
         IFWL_WidgetDelegate* pDelegate = m_pOwner->m_pEdit->SetDelegate(NULL);
-        return pDelegate->OnProcessMessage(pMessage);
+        pDelegate->OnProcessMessage(pMessage);
+        return;
       }
       break;
     }
@@ -1069,14 +1075,14 @@ int32_t CFWL_DateTimePickerImpDelegate::OnProcessMessage(
       break;
   }
 
-  return CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
+  CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
 }
 
-FWL_ERR CFWL_DateTimePickerImpDelegate::OnDrawWidget(
-    CFX_Graphics* pGraphics,
-    const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+void CFWL_DateTimePickerImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                                  const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
+
 void CFWL_DateTimePickerImpDelegate::OnFocusChanged(CFWL_Message* pMsg,
                                                     FX_BOOL bSet) {
   if (!pMsg)
diff --git a/xfa/fwl/basewidget/fwl_datetimepickerimp.h b/xfa/fwl/basewidget/fwl_datetimepickerimp.h
index 7276928332..3fd86bed05 100644
--- a/xfa/fwl/basewidget/fwl_datetimepickerimp.h
+++ b/xfa/fwl/basewidget/fwl_datetimepickerimp.h
@@ -58,8 +58,8 @@ class CFWL_DateTimeEdit : public CFWL_EditImp {
  public:
   CFWL_DateTimeEdit(const CFWL_WidgetImpProperties& properties,
                     IFWL_Widget* pOuter);
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
 
  protected:
   friend class CFWL_DateTimeEditImpDelegate;
@@ -67,10 +67,10 @@ class CFWL_DateTimeEdit : public CFWL_EditImp {
 class CFWL_DateTimeEditImpDelegate : public CFWL_EditImpDelegate {
  public:
   CFWL_DateTimeEditImpDelegate(CFWL_DateTimeEdit* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
 
  private:
-  int32_t DisForm_OnProcessMessage(CFWL_Message* pMessage);
+  void DisForm_OnProcessMessage(CFWL_Message* pMessage);
 
  protected:
   CFWL_DateTimeEdit* m_pOwner;
@@ -79,8 +79,8 @@ class CFWL_DateTimeCalendar : public CFWL_MonthCalendarImp {
  public:
   CFWL_DateTimeCalendar(const CFWL_WidgetImpProperties& properties,
                         IFWL_Widget* pOuter);
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
 
  protected:
   friend class CFWL_DateTimeCalendarImpDelegate;
@@ -88,14 +88,14 @@ class CFWL_DateTimeCalendar : public CFWL_MonthCalendarImp {
 class CFWL_DateTimeCalendarImpDelegate : public CFWL_MonthCalendarImpDelegate {
  public:
   CFWL_DateTimeCalendarImpDelegate(CFWL_DateTimeCalendar* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
 
   void OnLButtonDownEx(CFWL_MsgMouse* pMsg);
   void OnLButtonUpEx(CFWL_MsgMouse* pMsg);
   void OnMouseMoveEx(CFWL_MsgMouse* pMsg);
 
  private:
-  int32_t DisForm_OnProcessMessage(CFWL_Message* pMessage);
+  void DisForm_OnProcessMessage(CFWL_Message* pMessage);
   void DisForm_OnLButtonUpEx(CFWL_MsgMouse* pMsg);
 
  protected:
@@ -107,22 +107,22 @@ class CFWL_DateTimePickerImp : public CFWL_WidgetImp {
   CFWL_DateTimePickerImp(const CFWL_WidgetImpProperties& properties,
                          IFWL_Widget* pOuter);
   virtual ~CFWL_DateTimePickerImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  virtual FWL_ERR Update();
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error Update();
   virtual FWL_WidgetHit HitTest(FX_FLOAT fx, FX_FLOAT fy);
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
-  virtual FWL_ERR SetThemeProvider(IFWL_ThemeProvider* pTP);
-  virtual FWL_ERR GetCurSel(int32_t& iYear, int32_t& iMonth, int32_t& iDay);
-  virtual FWL_ERR SetCurSel(int32_t iYear, int32_t iMonth, int32_t iDay);
-  virtual FWL_ERR SetEditText(const CFX_WideString& wsText);
-  virtual FWL_ERR GetEditText(CFX_WideString& wsText,
-                              int32_t nStart = 0,
-                              int32_t nCount = -1) const;
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error SetThemeProvider(IFWL_ThemeProvider* pTP);
+  virtual FWL_Error GetCurSel(int32_t& iYear, int32_t& iMonth, int32_t& iDay);
+  virtual FWL_Error SetCurSel(int32_t iYear, int32_t iMonth, int32_t iDay);
+  virtual FWL_Error SetEditText(const CFX_WideString& wsText);
+  virtual FWL_Error GetEditText(CFX_WideString& wsText,
+                                int32_t nStart = 0,
+                                int32_t nCount = -1) const;
 
  public:
   virtual FX_BOOL CanUndo();
@@ -138,10 +138,10 @@ class CFWL_DateTimePickerImp : public CFWL_WidgetImp {
   virtual FX_BOOL SelectAll();
   virtual FX_BOOL Delete();
   virtual FX_BOOL DeSelect();
-  virtual FWL_ERR GetBBox(CFX_RectF& rect);
-  virtual FWL_ERR SetEditLimit(int32_t nLimit);
-  virtual FWL_ERR ModifyEditStylesEx(uint32_t dwStylesExAdded,
-                                     uint32_t dwStylesExRemoved);
+  virtual FWL_Error GetBBox(CFX_RectF& rect);
+  virtual FWL_Error SetEditLimit(int32_t nLimit);
+  virtual FWL_Error ModifyEditStylesEx(uint32_t dwStylesExAdded,
+                                       uint32_t dwStylesExRemoved);
 
  public:
   IFWL_DateTimeEdit* GetDataTimeEdit();
@@ -161,18 +161,18 @@ class CFWL_DateTimePickerImp : public CFWL_WidgetImp {
   void ProcessSelChanged(int32_t iYear, int32_t iMonth, int32_t iDay);
 
  private:
-  FWL_ERR DisForm_Initialize();
+  FWL_Error DisForm_Initialize();
   void DisForm_InitDateTimeCalendar();
   void DisForm_InitDateTimeEdit();
   FX_BOOL DisForm_IsMonthCalendarShowed();
   void DisForm_ShowMonthCalendar(FX_BOOL bActivate);
   FWL_WidgetHit DisForm_HitTest(FX_FLOAT fx, FX_FLOAT fy);
   FX_BOOL DisForm_IsNeedShowButton();
-  FWL_ERR DisForm_Update();
-  FWL_ERR DisForm_GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  FWL_ERR DisForm_GetBBox(CFX_RectF& rect);
-  FWL_ERR DisForm_DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  FWL_Error DisForm_Update();
+  FWL_Error DisForm_GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  FWL_Error DisForm_GetBBox(CFX_RectF& rect);
+  FWL_Error DisForm_DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
 
  protected:
   CFX_RectF m_rtBtn;
@@ -193,9 +193,9 @@ class CFWL_DateTimePickerImp : public CFWL_WidgetImp {
       m_iCurMonth = 3;
       m_iCurDay = 29;
     }
-    virtual FWL_ERR GetCaption(IFWL_Widget* pWidget,
-                               CFX_WideString& wsCaption) {
-      return FWL_ERR_Succeeded;
+    virtual FWL_Error GetCaption(IFWL_Widget* pWidget,
+                                 CFX_WideString& wsCaption) {
+      return FWL_Error::Succeeded;
     }
     virtual int32_t GetCurDay(IFWL_Widget* pWidget) { return m_iCurDay; }
     virtual int32_t GetCurMonth(IFWL_Widget* pWidget) { return m_iCurMonth; }
@@ -214,9 +214,9 @@ class CFWL_DateTimePickerImp : public CFWL_WidgetImp {
 class CFWL_DateTimePickerImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_DateTimePickerImpDelegate(CFWL_DateTimePickerImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void OnFocusChanged(CFWL_Message* pMsg, FX_BOOL bSet = TRUE);
diff --git a/xfa/fwl/basewidget/fwl_editimp.cpp b/xfa/fwl/basewidget/fwl_editimp.cpp
index bf4f911ea8..563519a475 100644
--- a/xfa/fwl/basewidget/fwl_editimp.cpp
+++ b/xfa/fwl/basewidget/fwl_editimp.cpp
@@ -74,18 +74,18 @@ IFWL_Edit* IFWL_Edit::CreateComboEdit(
   return pEdit;
 }
 IFWL_Edit::IFWL_Edit() {}
-FWL_ERR IFWL_Edit::SetText(const CFX_WideString& wsText) {
+FWL_Error IFWL_Edit::SetText(const CFX_WideString& wsText) {
   return static_cast<CFWL_EditImp*>(GetImpl())->SetText(wsText);
 }
 int32_t IFWL_Edit::GetTextLength() const {
   return static_cast<CFWL_EditImp*>(GetImpl())->GetTextLength();
 }
-FWL_ERR IFWL_Edit::GetText(CFX_WideString& wsText,
-                           int32_t nStart,
-                           int32_t nCount) const {
+FWL_Error IFWL_Edit::GetText(CFX_WideString& wsText,
+                             int32_t nStart,
+                             int32_t nCount) const {
   return static_cast<CFWL_EditImp*>(GetImpl())->GetText(wsText, nStart, nCount);
 }
-FWL_ERR IFWL_Edit::ClearText() {
+FWL_Error IFWL_Edit::ClearText() {
   return static_cast<CFWL_EditImp*>(GetImpl())->ClearText();
 }
 int32_t IFWL_Edit::GetCaretPos() const {
@@ -94,7 +94,7 @@ int32_t IFWL_Edit::GetCaretPos() const {
 int32_t IFWL_Edit::SetCaretPos(int32_t nIndex, FX_BOOL bBefore) {
   return static_cast<CFWL_EditImp*>(GetImpl())->SetCaretPos(nIndex, bBefore);
 }
-FWL_ERR IFWL_Edit::AddSelRange(int32_t nStart, int32_t nCount) {
+FWL_Error IFWL_Edit::AddSelRange(int32_t nStart, int32_t nCount) {
   return static_cast<CFWL_EditImp*>(GetImpl())->AddSelRange(nStart, nCount);
 }
 int32_t IFWL_Edit::CountSelRanges() {
@@ -103,39 +103,39 @@ int32_t IFWL_Edit::CountSelRanges() {
 int32_t IFWL_Edit::GetSelRange(int32_t nIndex, int32_t& nStart) {
   return static_cast<CFWL_EditImp*>(GetImpl())->GetSelRange(nIndex, nStart);
 }
-FWL_ERR IFWL_Edit::ClearSelections() {
+FWL_Error IFWL_Edit::ClearSelections() {
   return static_cast<CFWL_EditImp*>(GetImpl())->ClearSelections();
 }
 int32_t IFWL_Edit::GetLimit() {
   return static_cast<CFWL_EditImp*>(GetImpl())->GetLimit();
 }
-FWL_ERR IFWL_Edit::SetLimit(int32_t nLimit) {
+FWL_Error IFWL_Edit::SetLimit(int32_t nLimit) {
   return static_cast<CFWL_EditImp*>(GetImpl())->SetLimit(nLimit);
 }
-FWL_ERR IFWL_Edit::SetAliasChar(FX_WCHAR wAlias) {
+FWL_Error IFWL_Edit::SetAliasChar(FX_WCHAR wAlias) {
   return static_cast<CFWL_EditImp*>(GetImpl())->SetAliasChar(wAlias);
 }
-FWL_ERR IFWL_Edit::Insert(int32_t nStart,
-                          const FX_WCHAR* lpText,
-                          int32_t nLen) {
+FWL_Error IFWL_Edit::Insert(int32_t nStart,
+                            const FX_WCHAR* lpText,
+                            int32_t nLen) {
   return static_cast<CFWL_EditImp*>(GetImpl())->Insert(nStart, lpText, nLen);
 }
-FWL_ERR IFWL_Edit::DeleteSelections() {
+FWL_Error IFWL_Edit::DeleteSelections() {
   return static_cast<CFWL_EditImp*>(GetImpl())->DeleteSelections();
 }
-FWL_ERR IFWL_Edit::DeleteRange(int32_t nStart, int32_t nCount) {
+FWL_Error IFWL_Edit::DeleteRange(int32_t nStart, int32_t nCount) {
   return static_cast<CFWL_EditImp*>(GetImpl())->DeleteRange(nStart, nCount);
 }
-FWL_ERR IFWL_Edit::ReplaceSelections(const CFX_WideStringC& wsReplace) {
+FWL_Error IFWL_Edit::ReplaceSelections(const CFX_WideStringC& wsReplace) {
   return static_cast<CFWL_EditImp*>(GetImpl())->ReplaceSelections(wsReplace);
 }
-FWL_ERR IFWL_Edit::Replace(int32_t nStart,
-                           int32_t nLen,
-                           const CFX_WideStringC& wsReplace) {
+FWL_Error IFWL_Edit::Replace(int32_t nStart,
+                             int32_t nLen,
+                             const CFX_WideStringC& wsReplace) {
   return static_cast<CFWL_EditImp*>(GetImpl())
       ->Replace(nStart, nLen, wsReplace);
 }
-FWL_ERR IFWL_Edit::DoClipboard(int32_t iCmd) {
+FWL_Error IFWL_Edit::DoClipboard(int32_t iCmd) {
   return static_cast<CFWL_EditImp*>(GetImpl())->DoClipboard(iCmd);
 }
 FX_BOOL IFWL_Edit::Copy(CFX_WideString& wsCopy) {
@@ -168,20 +168,20 @@ FX_BOOL IFWL_Edit::CanUndo() {
 FX_BOOL IFWL_Edit::CanRedo() {
   return static_cast<CFWL_EditImp*>(GetImpl())->CanRedo();
 }
-FWL_ERR IFWL_Edit::SetTabWidth(FX_FLOAT fTabWidth, FX_BOOL bEquidistant) {
+FWL_Error IFWL_Edit::SetTabWidth(FX_FLOAT fTabWidth, FX_BOOL bEquidistant) {
   return static_cast<CFWL_EditImp*>(GetImpl())
       ->SetTabWidth(fTabWidth, bEquidistant);
 }
-FWL_ERR IFWL_Edit::SetOuter(IFWL_Widget* pOuter) {
+FWL_Error IFWL_Edit::SetOuter(IFWL_Widget* pOuter) {
   return static_cast<CFWL_EditImp*>(GetImpl())->SetOuter(pOuter);
 }
-FWL_ERR IFWL_Edit::SetNumberRange(int32_t iMin, int32_t iMax) {
+FWL_Error IFWL_Edit::SetNumberRange(int32_t iMin, int32_t iMax) {
   return static_cast<CFWL_EditImp*>(GetImpl())->SetNumberRange(iMin, iMax);
 }
-FWL_ERR IFWL_Edit::SetBackColor(uint32_t dwColor) {
+FWL_Error IFWL_Edit::SetBackColor(uint32_t dwColor) {
   return static_cast<CFWL_EditImp*>(GetImpl())->SetBackgroundColor(dwColor);
 }
-FWL_ERR IFWL_Edit::SetFont(const CFX_WideString& wsFont, FX_FLOAT fSize) {
+FWL_Error IFWL_Edit::SetFont(const CFX_WideString& wsFont, FX_FLOAT fSize) {
   return static_cast<CFWL_EditImp*>(GetImpl())->SetFont(wsFont, fSize);
 }
 void IFWL_Edit::SetScrollOffset(FX_FLOAT fScrollOffset) {
@@ -229,16 +229,16 @@ CFWL_EditImp::~CFWL_EditImp() {
   }
   ClearRecord();
 }
-FWL_ERR CFWL_EditImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_EditImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_Edit;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_EditImp::GetClassID() const {
   return FWL_CLASSHASH_Edit;
 }
-FWL_ERR CFWL_EditImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_EditImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   if (!m_pDelegate) {
     m_pDelegate = new CFWL_EditImpDelegate(this);
   }
@@ -246,9 +246,9 @@ FWL_ERR CFWL_EditImp::Initialize() {
   if (!m_pEdtEngine) {
     InitEngine();
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::Finalize() {
+FWL_Error CFWL_EditImp::Finalize() {
   if (m_pProperties->m_dwStates & FWL_WGTSTATE_Focused) {
     ShowCaret(FALSE);
   }
@@ -262,7 +262,7 @@ FWL_ERR CFWL_EditImp::Finalize() {
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_EditImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
+FWL_Error CFWL_EditImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   if (bAutoSize) {
     rect.Set(0, 0, 0, 0);
     if (m_pEdtEngine) {
@@ -294,7 +294,7 @@ FWL_ERR CFWL_EditImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
       }
     }
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 
 void CFWL_EditImp::SetStates(uint32_t dwStates, FX_BOOL bSet) {
@@ -305,25 +305,25 @@ void CFWL_EditImp::SetStates(uint32_t dwStates, FX_BOOL bSet) {
   CFWL_WidgetImp::SetStates(dwStates, bSet);
 }
 
-FWL_ERR CFWL_EditImp::SetWidgetRect(const CFX_RectF& rect) {
+FWL_Error CFWL_EditImp::SetWidgetRect(const CFX_RectF& rect) {
   return CFWL_WidgetImp::SetWidgetRect(rect);
 }
-FWL_ERR CFWL_EditImp::Update() {
+FWL_Error CFWL_EditImp::Update() {
   if (IsLocked()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   if (!m_pProperties->m_pThemeProvider) {
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
   }
   Layout();
   if (m_rtClient.IsEmpty()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   UpdateEditEngine();
   UpdateVAlignment();
   UpdateScroll();
   InitCaret();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 
 FWL_WidgetHit CFWL_EditImp::HitTest(FX_FLOAT fx, FX_FLOAT fy) {
@@ -492,14 +492,14 @@ void CFWL_EditImp::DrawSpellCheck(CFX_Graphics* pGraphics,
   }
   pGraphics->RestoreGraphState();
 }
-FWL_ERR CFWL_EditImp::DrawWidget(CFX_Graphics* pGraphics,
-                                 const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_EditImp::DrawWidget(CFX_Graphics* pGraphics,
+                                   const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (m_rtClient.IsEmpty()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   IFWL_ThemeProvider* pTheme = m_pProperties->m_pThemeProvider;
   if (!m_pWidgetMgr->IsFormDisabled()) {
@@ -518,11 +518,11 @@ FWL_ERR CFWL_EditImp::DrawWidget(CFX_Graphics* pGraphics,
   if (HasEdge()) {
     DrawEdge(pGraphics, CFWL_Part::Edge, pTheme, pMatrix);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::SetThemeProvider(IFWL_ThemeProvider* pThemeProvider) {
+FWL_Error CFWL_EditImp::SetThemeProvider(IFWL_ThemeProvider* pThemeProvider) {
   if (!pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (m_pHorzScrollBar) {
     m_pHorzScrollBar->SetThemeProvider(pThemeProvider);
   }
@@ -533,142 +533,173 @@ FWL_ERR CFWL_EditImp::SetThemeProvider(IFWL_ThemeProvider* pThemeProvider) {
     m_pCaret->SetThemeProvider(pThemeProvider);
   }
   m_pProperties->m_pThemeProvider = pThemeProvider;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::SetText(const CFX_WideString& wsText) {
+
+FWL_Error CFWL_EditImp::SetText(const CFX_WideString& wsText) {
   m_pEdtEngine->SetText(wsText);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
+
 int32_t CFWL_EditImp::GetTextLength() const {
   if (!m_pEdtEngine)
     return -1;
   return m_pEdtEngine->GetTextLength();
 }
-FWL_ERR CFWL_EditImp::GetText(CFX_WideString& wsText,
-                              int32_t nStart,
-                              int32_t nCount) const {
+
+FWL_Error CFWL_EditImp::GetText(CFX_WideString& wsText,
+                                int32_t nStart,
+                                int32_t nCount) const {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   m_pEdtEngine->GetText(wsText, nStart, nCount);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::ClearText() {
+
+FWL_Error CFWL_EditImp::ClearText() {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   m_pEdtEngine->ClearText();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
+
 int32_t CFWL_EditImp::GetCaretPos() const {
   if (!m_pEdtEngine)
     return -1;
   return m_pEdtEngine->GetCaretPos();
 }
+
 int32_t CFWL_EditImp::SetCaretPos(int32_t nIndex, FX_BOOL bBefore) {
   if (!m_pEdtEngine)
     return -1;
   return m_pEdtEngine->SetCaretPos(nIndex, bBefore);
 }
-FWL_ERR CFWL_EditImp::AddSelRange(int32_t nStart, int32_t nCount) {
+
+FWL_Error CFWL_EditImp::AddSelRange(int32_t nStart, int32_t nCount) {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   m_pEdtEngine->AddSelRange(nStart, nCount);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
+
 int32_t CFWL_EditImp::CountSelRanges() {
   if (!m_pEdtEngine)
     return 0;
   return m_pEdtEngine->CountSelRanges();
-  return FWL_ERR_Succeeded;
 }
+
 int32_t CFWL_EditImp::GetSelRange(int32_t nIndex, int32_t& nStart) {
   if (!m_pEdtEngine)
     return -1;
   return m_pEdtEngine->GetSelRange(nIndex, nStart);
 }
-FWL_ERR CFWL_EditImp::ClearSelections() {
+
+FWL_Error CFWL_EditImp::ClearSelections() {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   m_pEdtEngine->ClearSelection();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
+
 int32_t CFWL_EditImp::GetLimit() {
   return m_nLimit;
 }
-FWL_ERR CFWL_EditImp::SetLimit(int32_t nLimit) {
+
+FWL_Error CFWL_EditImp::SetLimit(int32_t nLimit) {
   m_nLimit = nLimit;
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   m_pEdtEngine->SetLimit(nLimit);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::SetAliasChar(FX_WCHAR wAlias) {
+
+FWL_Error CFWL_EditImp::SetAliasChar(FX_WCHAR wAlias) {
   if (!m_pEdtEngine)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
+
   m_pEdtEngine->SetAliasChar(wAlias);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::Insert(int32_t nStart,
-                             const FX_WCHAR* lpText,
-                             int32_t nLen) {
+
+FWL_Error CFWL_EditImp::Insert(int32_t nStart,
+                               const FX_WCHAR* lpText,
+                               int32_t nLen) {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   if ((m_pProperties->m_dwStyleExes & FWL_STYLEEXT_EDT_ReadOnly) ||
       (m_pProperties->m_dwStates & FWL_WGTSTATE_Disabled)) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   m_pEdtEngine->Insert(nStart, lpText, nLen);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::DeleteSelections() {
+
+FWL_Error CFWL_EditImp::DeleteSelections() {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   int32_t iCount = m_pEdtEngine->CountSelRanges();
-  if (iCount > 0) {
+  if (iCount > 0)
     m_pEdtEngine->Delete(-1);
-  }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::DeleteRange(int32_t nStart, int32_t nCount) {
+
+FWL_Error CFWL_EditImp::DeleteRange(int32_t nStart, int32_t nCount) {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   m_pEdtEngine->DeleteRange(nStart, nCount);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::ReplaceSelections(const CFX_WideStringC& wsReplace) {
+
+FWL_Error CFWL_EditImp::ReplaceSelections(const CFX_WideStringC& wsReplace) {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   int32_t iCount = m_pEdtEngine->CountSelRanges();
   for (int i = 0; i < iCount; i++) {
     int32_t nStart;
     int32_t nCount = m_pEdtEngine->GetSelRange(i, nStart);
     m_pEdtEngine->Replace(nStart, nCount, wsReplace);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::Replace(int32_t nStart,
-                              int32_t nLen,
-                              const CFX_WideStringC& wsReplace) {
+
+FWL_Error CFWL_EditImp::Replace(int32_t nStart,
+                                int32_t nLen,
+                                const CFX_WideStringC& wsReplace) {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   m_pEdtEngine->Replace(nStart, nLen, wsReplace);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::DoClipboard(int32_t iCmd) {
+
+FWL_Error CFWL_EditImp::DoClipboard(int32_t iCmd) {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   if ((m_pProperties->m_dwStyleExes & FWL_STYLEEXT_EDT_ReadOnly) ||
       (m_pProperties->m_dwStates & FWL_WGTSTATE_Disabled)) {
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Succeeded;
   }
-  return FWL_ERR_Indefinite;
+  return FWL_Error::Indefinite;
 }
+
 FX_BOOL CFWL_EditImp::Copy(CFX_WideString& wsCopy) {
   if (!m_pEdtEngine)
     return FALSE;
+
   int32_t nCount = m_pEdtEngine->CountSelRanges();
-  if (nCount == 0) {
+  if (nCount == 0)
     return FALSE;
-  }
+
   wsCopy.clear();
   CFX_WideString wsTemp;
   int32_t nStart, nLength;
@@ -680,13 +711,15 @@ FX_BOOL CFWL_EditImp::Copy(CFX_WideString& wsCopy) {
   }
   return TRUE;
 }
+
 FX_BOOL CFWL_EditImp::Cut(CFX_WideString& wsCut) {
   if (!m_pEdtEngine)
     return FALSE;
+
   int32_t nCount = m_pEdtEngine->CountSelRanges();
-  if (nCount == 0) {
+  if (nCount == 0)
     return FALSE;
-  }
+
   wsCut.clear();
   CFX_WideString wsTemp;
   int32_t nStart, nLength;
@@ -699,9 +732,11 @@ FX_BOOL CFWL_EditImp::Cut(CFX_WideString& wsCut) {
   m_pEdtEngine->Delete(0);
   return TRUE;
 }
+
 FX_BOOL CFWL_EditImp::Paste(const CFX_WideString& wsPaste) {
   if (!m_pEdtEngine)
     return FALSE;
+
   int32_t nCaret = m_pEdtEngine->GetCaretPos();
   int32_t iError =
       m_pEdtEngine->Insert(nCaret, wsPaste.c_str(), wsPaste.GetLength());
@@ -711,79 +746,89 @@ FX_BOOL CFWL_EditImp::Paste(const CFX_WideString& wsPaste) {
   }
   return TRUE;
 }
+
 FX_BOOL CFWL_EditImp::Delete() {
   if (!m_pEdtEngine)
     return FALSE;
+
   int32_t nCount = m_pEdtEngine->CountSelRanges();
-  if (nCount < 1) {
+  if (nCount < 1)
     return FALSE;
-  }
+
   m_pEdtEngine->Delete(0);
   return TRUE;
 }
+
 FX_BOOL CFWL_EditImp::Redo(const CFX_ByteStringC& bsRecord) {
   if (!m_pEdtEngine)
     return FALSE;
-  if (m_pProperties->m_dwStyleExes & FWL_STYLEEXT_EDT_NoRedoUndo) {
+  if (m_pProperties->m_dwStyleExes & FWL_STYLEEXT_EDT_NoRedoUndo)
     return TRUE;
-  }
   return m_pEdtEngine->Redo(bsRecord);
 }
+
 FX_BOOL CFWL_EditImp::Undo(const CFX_ByteStringC& bsRecord) {
   if (!m_pEdtEngine)
     return FALSE;
-  if (m_pProperties->m_dwStyleExes & FWL_STYLEEXT_EDT_NoRedoUndo) {
+  if (m_pProperties->m_dwStyleExes & FWL_STYLEEXT_EDT_NoRedoUndo)
     return TRUE;
-  }
   return m_pEdtEngine->Undo(bsRecord);
 }
+
 FX_BOOL CFWL_EditImp::Undo() {
-  if (!CanUndo()) {
+  if (!CanUndo())
     return FALSE;
-  }
+
   CFX_ByteString bsRecord = m_RecordArr[m_iCurRecord--];
   return Undo(bsRecord.AsStringC());
 }
+
 FX_BOOL CFWL_EditImp::Redo() {
-  if (!CanRedo()) {
+  if (!CanRedo())
     return FALSE;
-  }
+
   CFX_ByteString bsRecord = m_RecordArr[++m_iCurRecord];
   return Redo(bsRecord.AsStringC());
 }
+
 FX_BOOL CFWL_EditImp::CanUndo() {
   return m_iCurRecord >= 0;
 }
+
 FX_BOOL CFWL_EditImp::CanRedo() {
   return m_iCurRecord < m_RecordArr.GetSize() - 1;
 }
-FWL_ERR CFWL_EditImp::SetTabWidth(FX_FLOAT fTabWidth, FX_BOOL bEquidistant) {
+
+FWL_Error CFWL_EditImp::SetTabWidth(FX_FLOAT fTabWidth, FX_BOOL bEquidistant) {
   if (!m_pEdtEngine)
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Indefinite;
+
   FDE_TXTEDTPARAMS* pParams = m_pEdtEngine->GetEditParams();
   pParams->fTabWidth = fTabWidth;
   pParams->bTabEquidistant = bEquidistant;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::SetOuter(IFWL_Widget* pOuter) {
+
+FWL_Error CFWL_EditImp::SetOuter(IFWL_Widget* pOuter) {
   m_pOuter = pOuter;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::SetNumberRange(int32_t iMin, int32_t iMax) {
+
+FWL_Error CFWL_EditImp::SetNumberRange(int32_t iMin, int32_t iMax) {
   m_iMin = iMin;
   m_iMax = iMax;
   m_bSetRange = TRUE;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
+
 void CFWL_EditImp::On_CaretChanged(CFDE_TxtEdtEngine* pEdit,
                                    int32_t nPage,
                                    FX_BOOL bVisible) {
-  if (m_rtEngine.IsEmpty()) {
+  if (m_rtEngine.IsEmpty())
     return;
-  }
-  if ((m_pProperties->m_dwStates & FWL_WGTSTATE_Focused) == 0) {
+  if ((m_pProperties->m_dwStates & FWL_WGTSTATE_Focused) == 0)
     return;
-  }
+
   FX_BOOL bRepaintContent = UpdateOffset();
   UpdateCaret();
   CFX_RectF rtInvalid;
@@ -803,12 +848,13 @@ void CFWL_EditImp::On_CaretChanged(CFDE_TxtEdtEngine* pEdit,
     Repaint(&rtInvalid);
   }
 }
+
 void CFWL_EditImp::On_TextChanged(CFDE_TxtEdtEngine* pEdit,
                                   FDE_TXTEDT_TEXTCHANGE_INFO& ChangeInfo) {
   uint32_t dwStyleEx = m_pProperties->m_dwStyleExes;
-  if (dwStyleEx & FWL_STYLEEXT_EDT_VAlignMask) {
+  if (dwStyleEx & FWL_STYLEEXT_EDT_VAlignMask)
     UpdateVAlignment();
-  }
+
   IFDE_TxtEdtPage* page = m_pEdtEngine->GetPage(0);
   FX_FLOAT fContentWidth = page->GetContentsBox().width;
   FX_FLOAT fContentHeight = page->GetContentsBox().height;
@@ -913,15 +959,15 @@ FX_BOOL CFWL_EditImp::On_Validate(CFDE_TxtEdtEngine* pEdit,
   DispatchEvent(&event);
   return event.bValidate;
 }
-FWL_ERR CFWL_EditImp::SetBackgroundColor(uint32_t color) {
+FWL_Error CFWL_EditImp::SetBackgroundColor(uint32_t color) {
   m_backColor = color;
   m_updateBackColor = TRUE;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_EditImp::SetFont(const CFX_WideString& wsFont, FX_FLOAT fSize) {
+FWL_Error CFWL_EditImp::SetFont(const CFX_WideString& wsFont, FX_FLOAT fSize) {
   m_wsFont = wsFont;
   m_fFontSize = fSize;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 void CFWL_EditImp::SetScrollOffset(FX_FLOAT fScrollOffset) {
   m_fScrollOffsetY = fScrollOffset;
@@ -1718,12 +1764,11 @@ void CFWL_EditImp::ProcessInsertError(int32_t iError) {
 CFWL_EditImpDelegate::CFWL_EditImpDelegate(CFWL_EditImp* pOwner)
     : m_pOwner(pOwner) {}
 
-int32_t CFWL_EditImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+void CFWL_EditImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
 
   CFWL_MessageType dwMsgCode = pMessage->GetClassID();
-  int32_t iRet = 1;
   switch (dwMsgCode) {
     case CFWL_MessageType::Activate: {
       DoActivate(static_cast<CFWL_MsgActivate*>(pMessage));
@@ -1775,19 +1820,17 @@ int32_t CFWL_EditImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
       break;
     }
     default: {
-      iRet = 0;
       break;
     }
   }
   CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
-  return iRet;
 }
 
-FWL_ERR CFWL_EditImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
+void CFWL_EditImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
   if (!pEvent)
-    return FWL_ERR_Indefinite;
+    return;
   if (pEvent->GetClassID() != CFWL_EventType::Scroll)
-    return FWL_ERR_Succeeded;
+    return;
 
   IFWL_Widget* pSrcTarget = pEvent->m_pSrcTarget;
   if ((pSrcTarget == m_pOwner->m_pVertScrollBar.get() &&
@@ -1798,13 +1841,13 @@ FWL_ERR CFWL_EditImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
     OnScroll(static_cast<IFWL_ScrollBar*>(pSrcTarget),
              pScrollEvent->m_iScrollCode, pScrollEvent->m_fPos);
   }
-  return FWL_ERR_Succeeded;
 }
 
-FWL_ERR CFWL_EditImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                           const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+void CFWL_EditImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                        const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
+
 void CFWL_EditImpDelegate::DoActivate(CFWL_MsgActivate* pMsg) {
   m_pOwner->m_pProperties->m_dwStates |= ~FWL_WGTSTATE_Deactivated;
   m_pOwner->Repaint(&m_pOwner->m_rtClient);
diff --git a/xfa/fwl/basewidget/fwl_editimp.h b/xfa/fwl/basewidget/fwl_editimp.h
index 72f2ad03e4..96e56d0c33 100644
--- a/xfa/fwl/basewidget/fwl_editimp.h
+++ b/xfa/fwl/basewidget/fwl_editimp.h
@@ -30,42 +30,44 @@ class CFWL_EditImp : public CFWL_WidgetImp {
   ~CFWL_EditImp() override;
 
   // CFWL_WidgetImp:
-  FWL_ERR GetClassName(CFX_WideString& wsClass) const override;
+  FWL_Error GetClassName(CFX_WideString& wsClass) const override;
   uint32_t GetClassID() const override;
-  FWL_ERR Initialize() override;
-  FWL_ERR Finalize() override;
-  FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE) override;
-  FWL_ERR SetWidgetRect(const CFX_RectF& rect) override;
-  FWL_ERR Update() override;
+  FWL_Error Initialize() override;
+  FWL_Error Finalize() override;
+  FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE) override;
+  FWL_Error SetWidgetRect(const CFX_RectF& rect) override;
+  FWL_Error Update() override;
   FWL_WidgetHit HitTest(FX_FLOAT fx, FX_FLOAT fy) override;
   void SetStates(uint32_t dwStates, FX_BOOL bSet = TRUE) override;
-  FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                     const CFX_Matrix* pMatrix = NULL) override;
-  FWL_ERR SetThemeProvider(IFWL_ThemeProvider* pThemeProvider) override;
+  FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                       const CFX_Matrix* pMatrix = NULL) override;
+  FWL_Error SetThemeProvider(IFWL_ThemeProvider* pThemeProvider) override;
 
-  virtual FWL_ERR SetText(const CFX_WideString& wsText);
+  virtual FWL_Error SetText(const CFX_WideString& wsText);
   virtual int32_t GetTextLength() const;
-  virtual FWL_ERR GetText(CFX_WideString& wsText,
-                          int32_t nStart = 0,
-                          int32_t nCount = -1) const;
-  virtual FWL_ERR ClearText();
+  virtual FWL_Error GetText(CFX_WideString& wsText,
+                            int32_t nStart = 0,
+                            int32_t nCount = -1) const;
+  virtual FWL_Error ClearText();
   virtual int32_t GetCaretPos() const;
   virtual int32_t SetCaretPos(int32_t nIndex, FX_BOOL bBefore = TRUE);
-  virtual FWL_ERR AddSelRange(int32_t nStart, int32_t nCount = -1);
+  virtual FWL_Error AddSelRange(int32_t nStart, int32_t nCount = -1);
   virtual int32_t CountSelRanges();
   virtual int32_t GetSelRange(int32_t nIndex, int32_t& nStart);
-  virtual FWL_ERR ClearSelections();
+  virtual FWL_Error ClearSelections();
   virtual int32_t GetLimit();
-  virtual FWL_ERR SetLimit(int32_t nLimit);
-  virtual FWL_ERR SetAliasChar(FX_WCHAR wAlias);
-  virtual FWL_ERR Insert(int32_t nStart, const FX_WCHAR* lpText, int32_t nLen);
-  virtual FWL_ERR DeleteSelections();
-  virtual FWL_ERR DeleteRange(int32_t nStart, int32_t nCount = -1);
-  virtual FWL_ERR ReplaceSelections(const CFX_WideStringC& wsReplace);
-  virtual FWL_ERR Replace(int32_t nStart,
-                          int32_t nLen,
-                          const CFX_WideStringC& wsReplace);
-  virtual FWL_ERR DoClipboard(int32_t iCmd);
+  virtual FWL_Error SetLimit(int32_t nLimit);
+  virtual FWL_Error SetAliasChar(FX_WCHAR wAlias);
+  virtual FWL_Error Insert(int32_t nStart,
+                           const FX_WCHAR* lpText,
+                           int32_t nLen);
+  virtual FWL_Error DeleteSelections();
+  virtual FWL_Error DeleteRange(int32_t nStart, int32_t nCount = -1);
+  virtual FWL_Error ReplaceSelections(const CFX_WideStringC& wsReplace);
+  virtual FWL_Error Replace(int32_t nStart,
+                            int32_t nLen,
+                            const CFX_WideStringC& wsReplace);
+  virtual FWL_Error DoClipboard(int32_t iCmd);
   virtual FX_BOOL Copy(CFX_WideString& wsCopy);
   virtual FX_BOOL Cut(CFX_WideString& wsCut);
   virtual FX_BOOL Paste(const CFX_WideString& wsPaste);
@@ -76,11 +78,11 @@ class CFWL_EditImp : public CFWL_WidgetImp {
   virtual FX_BOOL Redo();
   virtual FX_BOOL CanUndo();
   virtual FX_BOOL CanRedo();
-  virtual FWL_ERR SetTabWidth(FX_FLOAT fTabWidth, FX_BOOL bEquidistant);
-  virtual FWL_ERR SetOuter(IFWL_Widget* pOuter);
-  virtual FWL_ERR SetNumberRange(int32_t iMin, int32_t iMax);
-  virtual FWL_ERR SetBackgroundColor(uint32_t color);
-  virtual FWL_ERR SetFont(const CFX_WideString& wsFont, FX_FLOAT fSize);
+  virtual FWL_Error SetTabWidth(FX_FLOAT fTabWidth, FX_BOOL bEquidistant);
+  virtual FWL_Error SetOuter(IFWL_Widget* pOuter);
+  virtual FWL_Error SetNumberRange(int32_t iMin, int32_t iMax);
+  virtual FWL_Error SetBackgroundColor(uint32_t color);
+  virtual FWL_Error SetFont(const CFX_WideString& wsFont, FX_FLOAT fSize);
 
   void On_CaretChanged(CFDE_TxtEdtEngine* pEdit,
                        int32_t nPage,
@@ -174,10 +176,10 @@ class CFWL_EditImp : public CFWL_WidgetImp {
 class CFWL_EditImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_EditImpDelegate(CFWL_EditImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnProcessEvent(CFWL_Event* pEvent) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessEvent(CFWL_Event* pEvent) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void DoActivate(CFWL_MsgActivate* pMsg);
diff --git a/xfa/fwl/basewidget/fwl_formproxyimp.cpp b/xfa/fwl/basewidget/fwl_formproxyimp.cpp
index 0a5bb67aec..1e70da64ad 100644
--- a/xfa/fwl/basewidget/fwl_formproxyimp.cpp
+++ b/xfa/fwl/basewidget/fwl_formproxyimp.cpp
@@ -14,9 +14,9 @@ CFWL_FormProxyImp::CFWL_FormProxyImp(const CFWL_WidgetImpProperties& properties,
                                      IFWL_Widget* pOuter)
     : CFWL_FormImp(properties, pOuter) {}
 CFWL_FormProxyImp::~CFWL_FormProxyImp() {}
-FWL_ERR CFWL_FormProxyImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_FormProxyImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_FormProxy;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_FormProxyImp::GetClassID() const {
   return FWL_CLASSHASH_FormProxy;
@@ -27,27 +27,29 @@ FX_BOOL CFWL_FormProxyImp::IsInstance(const CFX_WideStringC& wsClass) const {
   }
   return CFWL_FormImp::IsInstance(wsClass);
 }
-FWL_ERR CFWL_FormProxyImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_FormProxyImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_FormProxyImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_FormProxyImp::Finalize() {
+FWL_Error CFWL_FormProxyImp::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_FormProxyImp::Update() {
-  return FWL_ERR_Succeeded;
+FWL_Error CFWL_FormProxyImp::Update() {
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_FormProxyImp::DrawWidget(CFX_Graphics* pGraphics,
-                                      const CFX_Matrix* pMatrix) {
-  return FWL_ERR_Succeeded;
+FWL_Error CFWL_FormProxyImp::DrawWidget(CFX_Graphics* pGraphics,
+                                        const CFX_Matrix* pMatrix) {
+  return FWL_Error::Succeeded;
 }
+
 CFWL_FormProxyImpDelegate::CFWL_FormProxyImpDelegate(CFWL_FormProxyImp* pOwner)
     : m_pOwner(pOwner) {}
-int32_t CFWL_FormProxyImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+
+void CFWL_FormProxyImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   IFWL_WidgetDelegate* pDelegate = m_pOwner->m_pOuter->SetDelegate(NULL);
-  return pDelegate->OnProcessMessage(pMessage);
+  pDelegate->OnProcessMessage(pMessage);
 }
diff --git a/xfa/fwl/basewidget/fwl_formproxyimp.h b/xfa/fwl/basewidget/fwl_formproxyimp.h
index 4e5e807507..1fbff200ba 100644
--- a/xfa/fwl/basewidget/fwl_formproxyimp.h
+++ b/xfa/fwl/basewidget/fwl_formproxyimp.h
@@ -18,14 +18,14 @@ class CFWL_FormProxyImp : public CFWL_FormImp {
   CFWL_FormProxyImp(const CFWL_WidgetImpProperties& properties,
                     IFWL_Widget* pOuter);
   ~CFWL_FormProxyImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
   virtual FX_BOOL IsInstance(const CFX_WideStringC& wsClass) const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR Update();
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error Update();
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
 
  protected:
   friend class CFWL_FormProxyImpDelegate;
@@ -33,7 +33,7 @@ class CFWL_FormProxyImp : public CFWL_FormImp {
 class CFWL_FormProxyImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_FormProxyImpDelegate(CFWL_FormProxyImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
 
  protected:
   CFWL_FormProxyImp* m_pOwner;
diff --git a/xfa/fwl/basewidget/fwl_listboximp.cpp b/xfa/fwl/basewidget/fwl_listboximp.cpp
index 3a0df152c2..e585a17d7d 100644
--- a/xfa/fwl/basewidget/fwl_listboximp.cpp
+++ b/xfa/fwl/basewidget/fwl_listboximp.cpp
@@ -52,18 +52,16 @@ FWL_HLISTITEM IFWL_ListBox::GetSelItem(int32_t nIndexSel) {
 int32_t IFWL_ListBox::GetSelIndex(int32_t nIndex) {
   return static_cast<CFWL_ListBoxImp*>(GetImpl())->GetSelIndex(nIndex);
 }
-FWL_ERR IFWL_ListBox::SetSelItem(FWL_HLISTITEM hItem, FX_BOOL bSelect) {
+FWL_Error IFWL_ListBox::SetSelItem(FWL_HLISTITEM hItem, FX_BOOL bSelect) {
   return static_cast<CFWL_ListBoxImp*>(GetImpl())->SetSelItem(hItem, bSelect);
 }
-FWL_ERR IFWL_ListBox::GetItemText(FWL_HLISTITEM hItem, CFX_WideString& wsText) {
+FWL_Error IFWL_ListBox::GetItemText(FWL_HLISTITEM hItem,
+                                    CFX_WideString& wsText) {
   return static_cast<CFWL_ListBoxImp*>(GetImpl())->GetItemText(hItem, wsText);
 }
-FWL_ERR IFWL_ListBox::GetScrollPos(FX_FLOAT& fPos, FX_BOOL bVert) {
+FWL_Error IFWL_ListBox::GetScrollPos(FX_FLOAT& fPos, FX_BOOL bVert) {
   return static_cast<CFWL_ListBoxImp*>(GetImpl())->GetScrollPos(fPos, bVert);
 }
-FWL_ERR* IFWL_ListBox::Sort(IFWL_ListBoxCompare* pCom) {
-  return static_cast<CFWL_ListBoxImp*>(GetImpl())->Sort(pCom);
-}
 
 CFWL_ListBoxImp::CFWL_ListBoxImp(const CFWL_WidgetImpProperties& properties,
                                  IFWL_Widget* pOuter)
@@ -79,20 +77,20 @@ CFWL_ListBoxImp::CFWL_ListBoxImp(const CFWL_WidgetImpProperties& properties,
   m_rtStatic.Reset();
 }
 CFWL_ListBoxImp::~CFWL_ListBoxImp() {}
-FWL_ERR CFWL_ListBoxImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_ListBoxImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_ListBox;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_ListBoxImp::GetClassID() const {
   return FWL_CLASSHASH_ListBox;
 }
-FWL_ERR CFWL_ListBoxImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_ListBoxImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_ListBoxImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ListBoxImp::Finalize() {
+FWL_Error CFWL_ListBoxImp::Finalize() {
   if (m_pVertScrollBar) {
     m_pVertScrollBar->Finalize();
   }
@@ -103,7 +101,7 @@ FWL_ERR CFWL_ListBoxImp::Finalize() {
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_ListBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
+FWL_Error CFWL_ListBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   if (bAutoSize) {
     rect.Set(0, 0, 0, 0);
     if (!m_pProperties->m_pThemeProvider) {
@@ -115,11 +113,11 @@ FWL_ERR CFWL_ListBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   } else {
     rect = m_pProperties->m_rtWidget;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ListBoxImp::Update() {
+FWL_Error CFWL_ListBoxImp::Update() {
   if (IsLocked()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   if (!m_pProperties->m_pThemeProvider) {
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
@@ -142,9 +140,8 @@ FWL_ERR CFWL_ListBoxImp::Update() {
   }
   m_dwTTOStyles |= FDE_TTOSTYLE_SingleLine;
   m_fScorllBarWidth = GetScrollWidth();
-  SortItem();
   CalcSize();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FWL_WidgetHit CFWL_ListBoxImp::HitTest(FX_FLOAT fx, FX_FLOAT fy) {
   if (IsShowScrollBar(FALSE)) {
@@ -163,12 +160,12 @@ FWL_WidgetHit CFWL_ListBoxImp::HitTest(FX_FLOAT fx, FX_FLOAT fy) {
     return FWL_WidgetHit::Client;
   return FWL_WidgetHit::Unknown;
 }
-FWL_ERR CFWL_ListBoxImp::DrawWidget(CFX_Graphics* pGraphics,
-                                    const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_ListBoxImp::DrawWidget(CFX_Graphics* pGraphics,
+                                      const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   IFWL_ThemeProvider* pTheme = m_pProperties->m_pThemeProvider;
   pGraphics->SaveGraphState();
   if (HasBorder()) {
@@ -193,17 +190,18 @@ FWL_ERR CFWL_ListBoxImp::DrawWidget(CFX_Graphics* pGraphics,
   }
   DrawItems(pGraphics, pTheme, pMatrix);
   pGraphics->RestoreGraphState();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ListBoxImp::SetThemeProvider(IFWL_ThemeProvider* pThemeProvider) {
+FWL_Error CFWL_ListBoxImp::SetThemeProvider(
+    IFWL_ThemeProvider* pThemeProvider) {
   if (!pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!pThemeProvider->IsValidWidget(m_pInterface)) {
     m_pScrollBarTP = pThemeProvider;
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Succeeded;
   }
   m_pProperties->m_pThemeProvider = pThemeProvider;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 int32_t CFWL_ListBoxImp::CountSelItems() {
   if (!m_pProperties->m_pDataProvider)
@@ -270,9 +268,9 @@ int32_t CFWL_ListBoxImp::GetSelIndex(int32_t nIndex) {
   }
   return -1;
 }
-FWL_ERR CFWL_ListBoxImp::SetSelItem(FWL_HLISTITEM hItem, FX_BOOL bSelect) {
+FWL_Error CFWL_ListBoxImp::SetSelItem(FWL_HLISTITEM hItem, FX_BOOL bSelect) {
   if (!m_pProperties->m_pDataProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!hItem) {
     if (bSelect) {
       SelectAll();
@@ -280,52 +278,37 @@ FWL_ERR CFWL_ListBoxImp::SetSelItem(FWL_HLISTITEM hItem, FX_BOOL bSelect) {
       ClearSelection();
       SetFocusItem(NULL);
     }
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   if (m_pProperties->m_dwStyleExes & FWL_STYLEEXT_LTB_MultiSelection) {
     SetSelectionDirect(hItem, bSelect);
   } else {
     SetSelection(hItem, hItem, bSelect);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ListBoxImp::GetItemText(FWL_HLISTITEM hItem,
-                                     CFX_WideString& wsText) {
+FWL_Error CFWL_ListBoxImp::GetItemText(FWL_HLISTITEM hItem,
+                                       CFX_WideString& wsText) {
   if (!m_pProperties->m_pDataProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   IFWL_ListBoxDP* pData =
       static_cast<IFWL_ListBoxDP*>(m_pProperties->m_pDataProvider);
   if (!hItem)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   pData->GetItemText(m_pInterface, hItem, wsText);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ListBoxImp::GetScrollPos(FX_FLOAT& fPos, FX_BOOL bVert) {
+
+FWL_Error CFWL_ListBoxImp::GetScrollPos(FX_FLOAT& fPos, FX_BOOL bVert) {
   if ((bVert && IsShowScrollBar(TRUE)) || (!bVert && IsShowScrollBar(FALSE))) {
     IFWL_ScrollBar* pScrollBar =
         bVert ? m_pVertScrollBar.get() : m_pHorzScrollBar.get();
     fPos = pScrollBar->GetPos();
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Succeeded;
   }
-  return FWL_ERR_Indefinite;
-}
-FWL_ERR* CFWL_ListBoxImp::Sort(IFWL_ListBoxCompare* pCom) {
-  FWL_HLISTITEM hTemp;
-  IFWL_ListBoxDP* pData =
-      static_cast<IFWL_ListBoxDP*>(m_pProperties->m_pDataProvider);
-  int32_t sz = pData->CountItems(m_pInterface);
-  for (int32_t i = 0; i < sz - 1; i++) {
-    for (int32_t j = i + 1; j < sz; j++) {
-      if (pCom->Compare(pData->GetItem(m_pInterface, i),
-                        pData->GetItem(m_pInterface, j)) > 0) {
-        hTemp = pData->GetItem(m_pInterface, i);
-        pData->SetItemIndex(m_pInterface, pData->GetItem(m_pInterface, j), i);
-        pData->SetItemIndex(m_pInterface, hTemp, j);
-      }
-    }
-  }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Indefinite;
 }
+
 FWL_HLISTITEM CFWL_ListBoxImp::GetItem(FWL_HLISTITEM hItem,
                                        uint32_t dwKeyCode) {
   FWL_HLISTITEM hRet = NULL;
@@ -951,7 +934,7 @@ void CFWL_ListBoxImp::InitScrollBar(FX_BOOL bVert) {
   pScrollBar->Initialize();
   (bVert ? &m_pVertScrollBar : &m_pHorzScrollBar)->reset(pScrollBar);
 }
-void CFWL_ListBoxImp::SortItem() {}
+
 FX_BOOL CFWL_ListBoxImp::IsShowScrollBar(FX_BOOL bVert) {
   IFWL_ScrollBar* pScrollbar =
       bVert ? m_pVertScrollBar.get() : m_pHorzScrollBar.get();
@@ -980,14 +963,13 @@ void CFWL_ListBoxImp::ProcessSelChanged() {
 CFWL_ListBoxImpDelegate::CFWL_ListBoxImpDelegate(CFWL_ListBoxImp* pOwner)
     : m_pOwner(pOwner) {}
 
-int32_t CFWL_ListBoxImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+void CFWL_ListBoxImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
   if (!m_pOwner->IsEnabled())
-    return 1;
+    return;
 
   CFWL_MessageType dwMsgCode = pMessage->GetClassID();
-  int32_t iRet = 1;
   switch (dwMsgCode) {
     case CFWL_MessageType::SetFocus: {
       OnFocusChanged(pMessage, TRUE);
@@ -1024,19 +1006,17 @@ int32_t CFWL_ListBoxImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
       break;
     }
     default: {
-      iRet = 0;
       break;
     }
   }
   CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
-  return iRet;
 }
 
-FWL_ERR CFWL_ListBoxImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
+void CFWL_ListBoxImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
   if (!pEvent)
-    return FWL_ERR_Indefinite;
+    return;
   if (pEvent->GetClassID() != CFWL_EventType::Scroll)
-    return FWL_ERR_Succeeded;
+    return;
 
   IFWL_Widget* pSrcTarget = pEvent->m_pSrcTarget;
   if ((pSrcTarget == m_pOwner->m_pVertScrollBar.get() &&
@@ -1047,13 +1027,13 @@ FWL_ERR CFWL_ListBoxImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
     OnScroll(static_cast<IFWL_ScrollBar*>(pSrcTarget),
              pScrollEvent->m_iScrollCode, pScrollEvent->m_fPos);
   }
-  return FWL_ERR_Succeeded;
 }
 
-FWL_ERR CFWL_ListBoxImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                              const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+void CFWL_ListBoxImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                           const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
+
 void CFWL_ListBoxImpDelegate::OnFocusChanged(CFWL_Message* pMsg, FX_BOOL bSet) {
   if (m_pOwner->GetStylesEx() & FWL_STYLEEXT_LTB_ShowScrollBarFocus) {
     if (m_pOwner->m_pVertScrollBar) {
diff --git a/xfa/fwl/basewidget/fwl_listboximp.h b/xfa/fwl/basewidget/fwl_listboximp.h
index 65fbf6a45a..0d938fe778 100644
--- a/xfa/fwl/basewidget/fwl_listboximp.h
+++ b/xfa/fwl/basewidget/fwl_listboximp.h
@@ -25,23 +25,22 @@ class CFWL_ListBoxImp : public CFWL_WidgetImp {
   CFWL_ListBoxImp(const CFWL_WidgetImpProperties& properties,
                   IFWL_Widget* pOuter);
   ~CFWL_ListBoxImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  virtual FWL_ERR Update();
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error Update();
   virtual FWL_WidgetHit HitTest(FX_FLOAT fx, FX_FLOAT fy);
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
-  virtual FWL_ERR SetThemeProvider(IFWL_ThemeProvider* pThemeProvider);
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error SetThemeProvider(IFWL_ThemeProvider* pThemeProvider);
   virtual int32_t CountSelItems();
   virtual FWL_HLISTITEM GetSelItem(int32_t nIndexSel);
   virtual int32_t GetSelIndex(int32_t nIndex);
-  virtual FWL_ERR SetSelItem(FWL_HLISTITEM hItem, FX_BOOL bSelect = TRUE);
-  virtual FWL_ERR GetItemText(FWL_HLISTITEM hItem, CFX_WideString& wsText);
-  virtual FWL_ERR GetScrollPos(FX_FLOAT& fPos, FX_BOOL bVert = TRUE);
-  virtual FWL_ERR* Sort(IFWL_ListBoxCompare* pCom);
+  virtual FWL_Error SetSelItem(FWL_HLISTITEM hItem, FX_BOOL bSelect = TRUE);
+  virtual FWL_Error GetItemText(FWL_HLISTITEM hItem, CFX_WideString& wsText);
+  virtual FWL_Error GetScrollPos(FX_FLOAT& fPos, FX_BOOL bVert = TRUE);
 
  protected:
   FWL_HLISTITEM GetItem(FWL_HLISTITEM hItem, uint32_t dwKeyCode);
@@ -82,7 +81,6 @@ class CFWL_ListBoxImp : public CFWL_WidgetImp {
   FX_FLOAT GetScrollWidth();
   FX_FLOAT GetItemHeigt();
   void InitScrollBar(FX_BOOL bVert = TRUE);
-  void SortItem();
   FX_BOOL IsShowScrollBar(FX_BOOL bVert);
   void ProcessSelChanged();
 
@@ -104,10 +102,10 @@ class CFWL_ListBoxImp : public CFWL_WidgetImp {
 class CFWL_ListBoxImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_ListBoxImpDelegate(CFWL_ListBoxImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnProcessEvent(CFWL_Event* pEvent) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessEvent(CFWL_Event* pEvent) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void OnFocusChanged(CFWL_Message* pMsg, FX_BOOL bSet = TRUE);
diff --git a/xfa/fwl/basewidget/fwl_monthcalendarimp.cpp b/xfa/fwl/basewidget/fwl_monthcalendarimp.cpp
index 3feb1122a7..2d495d1fd5 100644
--- a/xfa/fwl/basewidget/fwl_monthcalendarimp.cpp
+++ b/xfa/fwl/basewidget/fwl_monthcalendarimp.cpp
@@ -180,26 +180,26 @@ CFWL_MonthCalendarImp::~CFWL_MonthCalendarImp() {
   delete m_pDateTime;
   m_arrSelDays.RemoveAll();
 }
-FWL_ERR CFWL_MonthCalendarImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_MonthCalendarImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_MonthCalendar;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_MonthCalendarImp::GetClassID() const {
   return FWL_CLASSHASH_MonthCalendar;
 }
-FWL_ERR CFWL_MonthCalendarImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_MonthCalendarImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_MonthCalendarImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_MonthCalendarImp::Finalize() {
+FWL_Error CFWL_MonthCalendarImp::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_MonthCalendarImp::GetWidgetRect(CFX_RectF& rect,
-                                             FX_BOOL bAutoSize) {
+FWL_Error CFWL_MonthCalendarImp::GetWidgetRect(CFX_RectF& rect,
+                                               FX_BOOL bAutoSize) {
   if (bAutoSize) {
     CFX_SizeF fs = CalcSize(TRUE);
     rect.Set(0, 0, fs.x, fs.y);
@@ -207,11 +207,11 @@ FWL_ERR CFWL_MonthCalendarImp::GetWidgetRect(CFX_RectF& rect,
   } else {
     rect = m_pProperties->m_rtWidget;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_MonthCalendarImp::Update() {
+FWL_Error CFWL_MonthCalendarImp::Update() {
   if (IsLocked()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   if (!m_pProperties->m_pThemeProvider) {
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
@@ -223,12 +223,12 @@ FWL_ERR CFWL_MonthCalendarImp::Update() {
   ClearDateItem();
   ReSetDateItem();
   LayOut();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_MonthCalendarImp::DrawWidget(CFX_Graphics* pGraphics,
-                                          const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_MonthCalendarImp::DrawWidget(CFX_Graphics* pGraphics,
+                                            const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (m_pProperties->m_pThemeProvider == NULL) {
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
   }
@@ -255,7 +255,7 @@ FWL_ERR CFWL_MonthCalendarImp::DrawWidget(CFX_Graphics* pGraphics,
     DrawWeekNumberSep(pGraphics, pTheme, pMatrix);
     DrawWeekNumber(pGraphics, pTheme, pMatrix);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 int32_t CFWL_MonthCalendarImp::CountSelect() {
   return m_arrSelDays.GetSize();
@@ -1017,13 +1017,11 @@ CFWL_MonthCalendarImpDelegate::CFWL_MonthCalendarImpDelegate(
     CFWL_MonthCalendarImp* pOwner)
     : m_pOwner(pOwner) {}
 
-int32_t CFWL_MonthCalendarImpDelegate::OnProcessMessage(
-    CFWL_Message* pMessage) {
+void CFWL_MonthCalendarImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
 
   CFWL_MessageType dwMsgCode = pMessage->GetClassID();
-  int32_t iRet = 1;
   switch (dwMsgCode) {
     case CFWL_MessageType::SetFocus: {
       OnFocusChanged(pMessage, TRUE);
@@ -1061,17 +1059,15 @@ int32_t CFWL_MonthCalendarImpDelegate::OnProcessMessage(
       break;
     }
     default: {
-      iRet = 0;
       break;
     }
   }
   CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
-  return iRet;
 }
 
-FWL_ERR CFWL_MonthCalendarImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                                    const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+void CFWL_MonthCalendarImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                                 const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
 
 void CFWL_MonthCalendarImpDelegate::OnActivate(CFWL_Message* pMsg) {}
diff --git a/xfa/fwl/basewidget/fwl_monthcalendarimp.h b/xfa/fwl/basewidget/fwl_monthcalendarimp.h
index a7deb9a098..d1096b40ce 100644
--- a/xfa/fwl/basewidget/fwl_monthcalendarimp.h
+++ b/xfa/fwl/basewidget/fwl_monthcalendarimp.h
@@ -24,14 +24,14 @@ class CFWL_MonthCalendarImp : public CFWL_WidgetImp {
   CFWL_MonthCalendarImp(const CFWL_WidgetImpProperties& properties,
                         IFWL_Widget* pOuter);
   ~CFWL_MonthCalendarImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  virtual FWL_ERR Update();
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error Update();
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
   virtual int32_t CountSelect();
   virtual FX_BOOL GetSelect(int32_t& iYear,
                             int32_t& iMonth,
@@ -229,9 +229,9 @@ struct FWL_DATEINFO {
 class CFWL_MonthCalendarImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_MonthCalendarImpDelegate(CFWL_MonthCalendarImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void OnActivate(CFWL_Message* pMsg);
diff --git a/xfa/fwl/basewidget/fwl_pictureboximp.cpp b/xfa/fwl/basewidget/fwl_pictureboximp.cpp
index 4495a495ba..c2cd09d342 100644
--- a/xfa/fwl/basewidget/fwl_pictureboximp.cpp
+++ b/xfa/fwl/basewidget/fwl_pictureboximp.cpp
@@ -35,29 +35,30 @@ CFWL_PictureBoxImp::CFWL_PictureBoxImp(
   m_matrix.SetIdentity();
 }
 CFWL_PictureBoxImp::~CFWL_PictureBoxImp() {}
-FWL_ERR CFWL_PictureBoxImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_PictureBoxImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_PictureBox;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_PictureBoxImp::GetClassID() const {
   return FWL_CLASSHASH_PictureBox;
 }
-FWL_ERR CFWL_PictureBoxImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_PictureBoxImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_PictureBoxImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_PictureBoxImp::Finalize() {
+FWL_Error CFWL_PictureBoxImp::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_PictureBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
+FWL_Error CFWL_PictureBoxImp::GetWidgetRect(CFX_RectF& rect,
+                                            FX_BOOL bAutoSize) {
   if (bAutoSize) {
     rect.Set(0, 0, 0, 0);
     if (!m_pProperties->m_pDataProvider)
-      return FWL_ERR_Indefinite;
+      return FWL_Error::Indefinite;
     CFX_DIBitmap* pBitmap =
         static_cast<IFWL_PictureBoxDP*>(m_pProperties->m_pDataProvider)
             ->GetPicture(m_pInterface);
@@ -69,24 +70,24 @@ FWL_ERR CFWL_PictureBoxImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   } else {
     rect = m_pProperties->m_rtWidget;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_PictureBoxImp::Update() {
+FWL_Error CFWL_PictureBoxImp::Update() {
   if (IsLocked()) {
-    return FWL_ERR_Succeeded;
+    return FWL_Error::Succeeded;
   }
   if (!m_pProperties->m_pThemeProvider) {
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
   }
   GetClientRect(m_rtClient);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_PictureBoxImp::DrawWidget(CFX_Graphics* pGraphics,
-                                       const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_PictureBoxImp::DrawWidget(CFX_Graphics* pGraphics,
+                                         const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   IFWL_ThemeProvider* pTheme = GetAvailableTheme();
   if (HasBorder()) {
     DrawBorder(pGraphics, CFWL_Part::Border, pTheme, pMatrix);
@@ -95,7 +96,7 @@ FWL_ERR CFWL_PictureBoxImp::DrawWidget(CFX_Graphics* pGraphics,
     DrawEdge(pGraphics, CFWL_Part::Edge, pTheme, pMatrix);
   }
   DrawBkground(pGraphics, pTheme, pMatrix);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 void CFWL_PictureBoxImp::DrawBkground(CFX_Graphics* pGraphics,
                                       IFWL_ThemeProvider* pTheme,
@@ -141,10 +142,12 @@ FX_BOOL CFWL_PictureBoxImp::VStyle(FX_BOOL dwStyle) {
   }
   return FALSE;
 }
+
 CFWL_PictureBoxImpDelegate::CFWL_PictureBoxImpDelegate(
     CFWL_PictureBoxImp* pOwner)
     : m_pOwner(pOwner) {}
-FWL_ERR CFWL_PictureBoxImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                                 const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+
+void CFWL_PictureBoxImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                              const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
diff --git a/xfa/fwl/basewidget/fwl_pictureboximp.h b/xfa/fwl/basewidget/fwl_pictureboximp.h
index f2e67124f6..d6f0ccc935 100644
--- a/xfa/fwl/basewidget/fwl_pictureboximp.h
+++ b/xfa/fwl/basewidget/fwl_pictureboximp.h
@@ -18,14 +18,14 @@ class CFWL_PictureBoxImp : public CFWL_WidgetImp {
   CFWL_PictureBoxImp(const CFWL_WidgetImpProperties& properties,
                      IFWL_Widget* pOuter);
   ~CFWL_PictureBoxImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  virtual FWL_ERR Update();
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error Update();
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
 
  protected:
   void DrawBkground(CFX_Graphics* pGraphics,
@@ -40,11 +40,12 @@ class CFWL_PictureBoxImp : public CFWL_WidgetImp {
   FX_BOOL m_bButton;
   friend class CFWL_PictureBoxImpDelegate;
 };
+
 class CFWL_PictureBoxImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_PictureBoxImpDelegate(CFWL_PictureBoxImp* pOwner);
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   CFWL_PictureBoxImp* m_pOwner;
diff --git a/xfa/fwl/basewidget/fwl_pushbuttonimp.cpp b/xfa/fwl/basewidget/fwl_pushbuttonimp.cpp
index 6fab925c91..3b18ad0fa0 100644
--- a/xfa/fwl/basewidget/fwl_pushbuttonimp.cpp
+++ b/xfa/fwl/basewidget/fwl_pushbuttonimp.cpp
@@ -39,25 +39,26 @@ CFWL_PushButtonImp::CFWL_PushButtonImp(
   m_rtCaption.Set(0, 0, 0, 0);
 }
 CFWL_PushButtonImp::~CFWL_PushButtonImp() {}
-FWL_ERR CFWL_PushButtonImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_PushButtonImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_PushButton;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_PushButtonImp::GetClassID() const {
   return FWL_CLASSHASH_PushButton;
 }
-FWL_ERR CFWL_PushButtonImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_PushButtonImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_PushButtonImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_PushButtonImp::Finalize() {
+FWL_Error CFWL_PushButtonImp::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_PushButtonImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
+FWL_Error CFWL_PushButtonImp::GetWidgetRect(CFX_RectF& rect,
+                                            FX_BOOL bAutoSize) {
   if (bAutoSize) {
     rect.Set(0, 0, 0, 0);
     if (m_pProperties->m_pThemeProvider == NULL) {
@@ -81,7 +82,7 @@ FWL_ERR CFWL_PushButtonImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   } else {
     rect = m_pProperties->m_rtWidget;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 
 void CFWL_PushButtonImp::SetStates(uint32_t dwStates, FX_BOOL bSet) {
@@ -92,9 +93,9 @@ void CFWL_PushButtonImp::SetStates(uint32_t dwStates, FX_BOOL bSet) {
   CFWL_WidgetImp::SetStates(dwStates, bSet);
 }
 
-FWL_ERR CFWL_PushButtonImp::Update() {
+FWL_Error CFWL_PushButtonImp::Update() {
   if (IsLocked()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   if (!m_pProperties->m_pThemeProvider) {
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
@@ -105,14 +106,14 @@ FWL_ERR CFWL_PushButtonImp::Update() {
   FX_FLOAT* fcaption =
       static_cast<FX_FLOAT*>(GetThemeCapacity(CFWL_WidgetCapacity::Margin));
   m_rtCaption.Inflate(-*fcaption, -*fcaption);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_PushButtonImp::DrawWidget(CFX_Graphics* pGraphics,
-                                       const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_PushButtonImp::DrawWidget(CFX_Graphics* pGraphics,
+                                         const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   IFWL_PushButtonDP* pData =
       static_cast<IFWL_PushButtonDP*>(m_pProperties->m_pDataProvider);
   CFX_DIBitmap* pPicture = NULL;
@@ -293,7 +294,7 @@ FWL_ERR CFWL_PushButtonImp::DrawWidget(CFX_Graphics* pGraphics,
       DrawText(pGraphics, m_pProperties->m_pThemeProvider, &matrix);
       break;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 void CFWL_PushButtonImp::DrawBkground(CFX_Graphics* pGraphics,
                                       IFWL_ThemeProvider* pTheme,
@@ -404,13 +405,12 @@ CFWL_PushButtonImpDelegate::CFWL_PushButtonImpDelegate(
     CFWL_PushButtonImp* pOwner)
     : m_pOwner(pOwner) {}
 
-int32_t CFWL_PushButtonImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+void CFWL_PushButtonImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
   if (!m_pOwner->IsEnabled())
-    return 1;
+    return;
 
-  int32_t iRet = 1;
   CFWL_MessageType dwMsgCode = pMessage->GetClassID();
   switch (dwMsgCode) {
     case CFWL_MessageType::SetFocus: {
@@ -452,21 +452,19 @@ int32_t CFWL_PushButtonImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
       break;
     }
     default: {
-      iRet = 0;
       break;
     }
   }
   CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
-  return iRet;
 }
 
-FWL_ERR CFWL_PushButtonImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
-  return FWL_ERR_Succeeded;
-}
-FWL_ERR CFWL_PushButtonImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                                 const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+void CFWL_PushButtonImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {}
+
+void CFWL_PushButtonImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                              const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
+
 void CFWL_PushButtonImpDelegate::OnFocusChanged(CFWL_Message* pMsg,
                                                 FX_BOOL bSet) {
   if (bSet) {
diff --git a/xfa/fwl/basewidget/fwl_pushbuttonimp.h b/xfa/fwl/basewidget/fwl_pushbuttonimp.h
index 50a984f5c1..89913be6c1 100644
--- a/xfa/fwl/basewidget/fwl_pushbuttonimp.h
+++ b/xfa/fwl/basewidget/fwl_pushbuttonimp.h
@@ -19,15 +19,15 @@ class CFWL_PushButtonImp : public CFWL_WidgetImp {
   CFWL_PushButtonImp(const CFWL_WidgetImpProperties& properties,
                      IFWL_Widget* pOuter);
   virtual ~CFWL_PushButtonImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
   virtual void SetStates(uint32_t dwStates, FX_BOOL bSet = TRUE);
-  virtual FWL_ERR Update();
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error Update();
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
 
  protected:
   void DrawBkground(CFX_Graphics* pGraphics,
@@ -49,10 +49,10 @@ class CFWL_PushButtonImp : public CFWL_WidgetImp {
 class CFWL_PushButtonImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_PushButtonImpDelegate(CFWL_PushButtonImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnProcessEvent(CFWL_Event* pEvent) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessEvent(CFWL_Event* pEvent) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void OnFocusChanged(CFWL_Message* pMsg, FX_BOOL bSet = TRUE);
diff --git a/xfa/fwl/basewidget/fwl_scrollbarimp.cpp b/xfa/fwl/basewidget/fwl_scrollbarimp.cpp
index 0db7c29e9d..b03846da91 100644
--- a/xfa/fwl/basewidget/fwl_scrollbarimp.cpp
+++ b/xfa/fwl/basewidget/fwl_scrollbarimp.cpp
@@ -31,34 +31,34 @@ IFWL_ScrollBar::IFWL_ScrollBar() {}
 FX_BOOL IFWL_ScrollBar::IsVertical() {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->IsVertical();
 }
-FWL_ERR IFWL_ScrollBar::GetRange(FX_FLOAT& fMin, FX_FLOAT& fMax) {
+FWL_Error IFWL_ScrollBar::GetRange(FX_FLOAT& fMin, FX_FLOAT& fMax) {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->GetRange(fMin, fMax);
 }
-FWL_ERR IFWL_ScrollBar::SetRange(FX_FLOAT fMin, FX_FLOAT fMax) {
+FWL_Error IFWL_ScrollBar::SetRange(FX_FLOAT fMin, FX_FLOAT fMax) {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->SetRange(fMin, fMax);
 }
 FX_FLOAT IFWL_ScrollBar::GetPageSize() {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->GetPageSize();
 }
-FWL_ERR IFWL_ScrollBar::SetPageSize(FX_FLOAT fPageSize) {
+FWL_Error IFWL_ScrollBar::SetPageSize(FX_FLOAT fPageSize) {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->SetPageSize(fPageSize);
 }
 FX_FLOAT IFWL_ScrollBar::GetStepSize() {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->GetStepSize();
 }
-FWL_ERR IFWL_ScrollBar::SetStepSize(FX_FLOAT fStepSize) {
+FWL_Error IFWL_ScrollBar::SetStepSize(FX_FLOAT fStepSize) {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->SetStepSize(fStepSize);
 }
 FX_FLOAT IFWL_ScrollBar::GetPos() {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->GetPos();
 }
-FWL_ERR IFWL_ScrollBar::SetPos(FX_FLOAT fPos) {
+FWL_Error IFWL_ScrollBar::SetPos(FX_FLOAT fPos) {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->SetPos(fPos);
 }
 FX_FLOAT IFWL_ScrollBar::GetTrackPos() {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->GetTrackPos();
 }
-FWL_ERR IFWL_ScrollBar::SetTrackPos(FX_FLOAT fTrackPos) {
+FWL_Error IFWL_ScrollBar::SetTrackPos(FX_FLOAT fTrackPos) {
   return static_cast<CFWL_ScrollBarImp*>(GetImpl())->SetTrackPos(fTrackPos);
 }
 FX_BOOL IFWL_ScrollBar::DoScroll(uint32_t dwCode, FX_FLOAT fPos) {
@@ -99,31 +99,31 @@ CFWL_ScrollBarImp::CFWL_ScrollBarImp(const CFWL_WidgetImpProperties& properties,
   m_rtMaxTrack.Reset();
 }
 CFWL_ScrollBarImp::~CFWL_ScrollBarImp() {}
-FWL_ERR CFWL_ScrollBarImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_ScrollBarImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_ScrollBar;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_ScrollBarImp::GetClassID() const {
   return FWL_CLASSHASH_ScrollBar;
 }
-FWL_ERR CFWL_ScrollBarImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_ScrollBarImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_ScrollBarImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ScrollBarImp::Finalize() {
+FWL_Error CFWL_ScrollBarImp::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_ScrollBarImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
+FWL_Error CFWL_ScrollBarImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   if (bAutoSize) {
     rect.Set(0, 0, 0, 0);
     FX_FLOAT* pfMinWidth = static_cast<FX_FLOAT*>(
         GetThemeCapacity(CFWL_WidgetCapacity::ScrollBarWidth));
     if (!pfMinWidth)
-      return FWL_ERR_Indefinite;
+      return FWL_Error::Indefinite;
     if (IsVertical()) {
       rect.Set(0, 0, (*pfMinWidth), (*pfMinWidth) * 3);
     } else {
@@ -133,24 +133,24 @@ FWL_ERR CFWL_ScrollBarImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   } else {
     rect = m_pProperties->m_rtWidget;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ScrollBarImp::Update() {
+FWL_Error CFWL_ScrollBarImp::Update() {
   if (IsLocked()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   if (!m_pProperties->m_pThemeProvider) {
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
   }
   Layout();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ScrollBarImp::DrawWidget(CFX_Graphics* pGraphics,
-                                      const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_ScrollBarImp::DrawWidget(CFX_Graphics* pGraphics,
+                                        const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   IFWL_ThemeProvider* pTheme = m_pProperties->m_pThemeProvider;
   if (HasBorder()) {
     DrawBorder(pGraphics, CFWL_Part::Border, pTheme, pMatrix);
@@ -163,51 +163,51 @@ FWL_ERR CFWL_ScrollBarImp::DrawWidget(CFX_Graphics* pGraphics,
   DrawArrowBtn(pGraphics, pTheme, TRUE, pMatrix);
   DrawArrowBtn(pGraphics, pTheme, FALSE, pMatrix);
   DrawThumb(pGraphics, pTheme, pMatrix);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 inline FX_BOOL CFWL_ScrollBarImp::IsVertical() {
   return m_pProperties->m_dwStyleExes & FWL_STYLEEXT_SCB_Vert;
 }
-FWL_ERR CFWL_ScrollBarImp::GetRange(FX_FLOAT& fMin, FX_FLOAT& fMax) {
+FWL_Error CFWL_ScrollBarImp::GetRange(FX_FLOAT& fMin, FX_FLOAT& fMax) {
   fMin = m_fRangeMin;
   fMax = m_fRangeMax;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ScrollBarImp::SetRange(FX_FLOAT fMin, FX_FLOAT fMax) {
+FWL_Error CFWL_ScrollBarImp::SetRange(FX_FLOAT fMin, FX_FLOAT fMax) {
   m_fRangeMin = fMin;
   m_fRangeMax = fMax;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FX_FLOAT CFWL_ScrollBarImp::GetPageSize() {
   return m_fPageSize;
 }
-FWL_ERR CFWL_ScrollBarImp::SetPageSize(FX_FLOAT fPageSize) {
+FWL_Error CFWL_ScrollBarImp::SetPageSize(FX_FLOAT fPageSize) {
   m_fPageSize = fPageSize;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FX_FLOAT CFWL_ScrollBarImp::GetStepSize() {
   return m_fStepSize;
 }
-FWL_ERR CFWL_ScrollBarImp::SetStepSize(FX_FLOAT fStepSize) {
+FWL_Error CFWL_ScrollBarImp::SetStepSize(FX_FLOAT fStepSize) {
   m_fStepSize = fStepSize;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FX_FLOAT CFWL_ScrollBarImp::GetPos() {
   return m_fPos;
 }
-FWL_ERR CFWL_ScrollBarImp::SetPos(FX_FLOAT fPos) {
+FWL_Error CFWL_ScrollBarImp::SetPos(FX_FLOAT fPos) {
   m_fPos = fPos;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FX_FLOAT CFWL_ScrollBarImp::GetTrackPos() {
   return m_fTrackPos;
 }
-FWL_ERR CFWL_ScrollBarImp::SetTrackPos(FX_FLOAT fTrackPos) {
+FWL_Error CFWL_ScrollBarImp::SetTrackPos(FX_FLOAT fTrackPos) {
   m_fTrackPos = fTrackPos;
   CalcThumbButtonRect(m_rtThumb);
   CalcMinTrackRect(m_rtMinTrack);
   CalcMaxTrackRect(m_rtMaxTrack);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FX_BOOL CFWL_ScrollBarImp::DoScroll(uint32_t dwCode, FX_FLOAT fPos) {
   switch (dwCode) {
@@ -236,9 +236,9 @@ int32_t CFWL_ScrollBarImp::Run(FWL_HTIMER hTimer) {
   }
   return 1;
 }
-FWL_ERR CFWL_ScrollBarImp::SetOuter(IFWL_Widget* pOuter) {
+FWL_Error CFWL_ScrollBarImp::SetOuter(IFWL_Widget* pOuter) {
   m_pOuter = pOuter;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 void CFWL_ScrollBarImp::DrawTrack(CFX_Graphics* pGraphics,
                                   IFWL_ThemeProvider* pTheme,
@@ -628,11 +628,10 @@ FX_BOOL CFWL_ScrollBarImp::OnScroll(uint32_t dwCode, FX_FLOAT fPos) {
 CFWL_ScrollBarImpDelegate::CFWL_ScrollBarImpDelegate(CFWL_ScrollBarImp* pOwner)
     : m_pOwner(pOwner) {}
 
-int32_t CFWL_ScrollBarImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+void CFWL_ScrollBarImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
 
-  int32_t iRet = 1;
   CFWL_MessageType dwMsgCode = pMessage->GetClassID();
   if (dwMsgCode == CFWL_MessageType::Mouse) {
     CFWL_MsgMouse* pMsg = static_cast<CFWL_MsgMouse*>(pMessage);
@@ -654,7 +653,6 @@ int32_t CFWL_ScrollBarImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
         break;
       }
       default: {
-        iRet = 0;
         break;
       }
     }
@@ -662,16 +660,14 @@ int32_t CFWL_ScrollBarImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
     CFWL_MsgMouseWheel* pMsg = static_cast<CFWL_MsgMouseWheel*>(pMessage);
     OnMouseWheel(pMsg->m_fx, pMsg->m_fy, pMsg->m_dwFlags, pMsg->m_fDeltaX,
                  pMsg->m_fDeltaY);
-  } else {
-    iRet = 0;
   }
-  return iRet;
 }
 
-FWL_ERR CFWL_ScrollBarImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                                const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+void CFWL_ScrollBarImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                             const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
+
 void CFWL_ScrollBarImpDelegate::OnLButtonDown(uint32_t dwFlags,
                                               FX_FLOAT fx,
                                               FX_FLOAT fy) {
diff --git a/xfa/fwl/basewidget/fwl_scrollbarimp.h b/xfa/fwl/basewidget/fwl_scrollbarimp.h
index 08f7c69bf7..6cee702f5c 100644
--- a/xfa/fwl/basewidget/fwl_scrollbarimp.h
+++ b/xfa/fwl/basewidget/fwl_scrollbarimp.h
@@ -19,27 +19,27 @@ class CFWL_ScrollBarImp : public CFWL_WidgetImp, public IFWL_Timer {
   CFWL_ScrollBarImp(const CFWL_WidgetImpProperties& properties,
                     IFWL_Widget* pOuter);
   ~CFWL_ScrollBarImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  virtual FWL_ERR Update();
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error Update();
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
   virtual FX_BOOL IsVertical();
-  virtual FWL_ERR GetRange(FX_FLOAT& fMin, FX_FLOAT& fMax);
-  virtual FWL_ERR SetRange(FX_FLOAT fMin, FX_FLOAT fMax);
+  virtual FWL_Error GetRange(FX_FLOAT& fMin, FX_FLOAT& fMax);
+  virtual FWL_Error SetRange(FX_FLOAT fMin, FX_FLOAT fMax);
   virtual FX_FLOAT GetPageSize();
-  virtual FWL_ERR SetPageSize(FX_FLOAT fPageSize);
+  virtual FWL_Error SetPageSize(FX_FLOAT fPageSize);
   virtual FX_FLOAT GetStepSize();
-  virtual FWL_ERR SetStepSize(FX_FLOAT fStepSize);
+  virtual FWL_Error SetStepSize(FX_FLOAT fStepSize);
   virtual FX_FLOAT GetPos();
-  virtual FWL_ERR SetPos(FX_FLOAT fPos);
+  virtual FWL_Error SetPos(FX_FLOAT fPos);
   virtual FX_FLOAT GetTrackPos();
-  virtual FWL_ERR SetTrackPos(FX_FLOAT fTrackPos);
+  virtual FWL_Error SetTrackPos(FX_FLOAT fTrackPos);
   virtual FX_BOOL DoScroll(uint32_t dwCode, FX_FLOAT fPos = 0.0f);
-  virtual FWL_ERR SetOuter(IFWL_Widget* pOuter);
+  virtual FWL_Error SetOuter(IFWL_Widget* pOuter);
   virtual int32_t Run(FWL_HTIMER hTimer);
 
  protected:
@@ -101,9 +101,9 @@ class CFWL_ScrollBarImp : public CFWL_WidgetImp, public IFWL_Timer {
 class CFWL_ScrollBarImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_ScrollBarImpDelegate(CFWL_ScrollBarImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void OnLButtonDown(uint32_t dwFlags, FX_FLOAT fx, FX_FLOAT fy);
diff --git a/xfa/fwl/basewidget/fwl_spinbuttonimp.cpp b/xfa/fwl/basewidget/fwl_spinbuttonimp.cpp
index 9a70d7187d..27b84bae92 100644
--- a/xfa/fwl/basewidget/fwl_spinbuttonimp.cpp
+++ b/xfa/fwl/basewidget/fwl_spinbuttonimp.cpp
@@ -36,7 +36,7 @@ IFWL_SpinButton* IFWL_SpinButton::Create(
   return pSpinButton;
 }
 IFWL_SpinButton::IFWL_SpinButton() {}
-FWL_ERR IFWL_SpinButton::EnableButton(FX_BOOL bEnable, FX_BOOL bUp) {
+FWL_Error IFWL_SpinButton::EnableButton(FX_BOOL bEnable, FX_BOOL bUp) {
   return static_cast<CFWL_SpinButtonImp*>(GetImpl())
       ->EnableButton(bEnable, bUp);
 }
@@ -59,36 +59,37 @@ CFWL_SpinButtonImp::CFWL_SpinButtonImp(
   m_pProperties->m_dwStyleExes |= FWL_STYLEEXE_SPB_Vert;
 }
 CFWL_SpinButtonImp::~CFWL_SpinButtonImp() {}
-FWL_ERR CFWL_SpinButtonImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_SpinButtonImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_SpinButton;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_SpinButtonImp::GetClassID() const {
   return FWL_CLASSHASH_SpinButton;
 }
-FWL_ERR CFWL_SpinButtonImp::Initialize() {
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+FWL_Error CFWL_SpinButtonImp::Initialize() {
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_SpinButtonImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_SpinButtonImp::Finalize() {
+FWL_Error CFWL_SpinButtonImp::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_SpinButtonImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
+FWL_Error CFWL_SpinButtonImp::GetWidgetRect(CFX_RectF& rect,
+                                            FX_BOOL bAutoSize) {
   if (bAutoSize) {
     rect.Set(0, 0, kMinWidth, kMinHeight);
     CFWL_WidgetImp::GetWidgetRect(rect, TRUE);
   } else {
     rect = m_pProperties->m_rtWidget;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_SpinButtonImp::Update() {
+FWL_Error CFWL_SpinButtonImp::Update() {
   if (IsLocked()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   GetClientRect(m_rtClient);
   if (m_pProperties->m_dwStyleExes & FWL_STYLEEXE_SPB_Vert) {
@@ -102,7 +103,7 @@ FWL_ERR CFWL_SpinButtonImp::Update() {
     m_rtDnButton.Set(m_rtClient.left + m_rtClient.width / 2, m_rtClient.top,
                      m_rtClient.width / 2, m_rtClient.height);
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FWL_WidgetHit CFWL_SpinButtonImp::HitTest(FX_FLOAT fx, FX_FLOAT fy) {
   if (m_rtClient.Contains(fx, fy))
@@ -121,10 +122,10 @@ FWL_WidgetHit CFWL_SpinButtonImp::HitTest(FX_FLOAT fx, FX_FLOAT fy) {
     return FWL_WidgetHit::DownButton;
   return FWL_WidgetHit::Unknown;
 }
-FWL_ERR CFWL_SpinButtonImp::DrawWidget(CFX_Graphics* pGraphics,
-                                       const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_SpinButtonImp::DrawWidget(CFX_Graphics* pGraphics,
+                                         const CFX_Matrix* pMatrix) {
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   CFX_RectF rtClip(m_rtClient);
   if (pMatrix != NULL) {
     pMatrix->TransformRect(rtClip);
@@ -138,7 +139,7 @@ FWL_ERR CFWL_SpinButtonImp::DrawWidget(CFX_Graphics* pGraphics,
   }
   DrawUpButton(pGraphics, pTheme, pMatrix);
   DrawDownButton(pGraphics, pTheme, pMatrix);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 int32_t CFWL_SpinButtonImp::Run(FWL_HTIMER hTimer) {
   if (m_hTimer) {
@@ -149,7 +150,7 @@ int32_t CFWL_SpinButtonImp::Run(FWL_HTIMER hTimer) {
   }
   return 1;
 }
-FWL_ERR CFWL_SpinButtonImp::EnableButton(FX_BOOL bEnable, FX_BOOL bUp) {
+FWL_Error CFWL_SpinButtonImp::EnableButton(FX_BOOL bEnable, FX_BOOL bUp) {
   if (bUp) {
     if (bEnable) {
       m_dwUpState = CFWL_PartState_Normal;
@@ -163,7 +164,7 @@ FWL_ERR CFWL_SpinButtonImp::EnableButton(FX_BOOL bEnable, FX_BOOL bUp) {
       m_dwDnState = CFWL_PartState_Disabled;
     }
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 FX_BOOL CFWL_SpinButtonImp::IsButtonEnable(FX_BOOL bUp) {
   if (bUp) {
@@ -204,11 +205,10 @@ CFWL_SpinButtonImpDelegate::CFWL_SpinButtonImpDelegate(
     CFWL_SpinButtonImp* pOwner)
     : m_pOwner(pOwner) {}
 
-int32_t CFWL_SpinButtonImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+void CFWL_SpinButtonImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
   if (!pMessage)
-    return 0;
+    return;
 
-  int32_t iRet = 1;
   CFWL_MessageType dwMsgCode = pMessage->GetClassID();
   switch (dwMsgCode) {
     case CFWL_MessageType::SetFocus: {
@@ -250,21 +250,19 @@ int32_t CFWL_SpinButtonImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
       break;
     }
     default: {
-      iRet = 0;
       break;
     }
   }
   CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
-  return iRet;
 }
 
-FWL_ERR CFWL_SpinButtonImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
-  return FWL_ERR_Succeeded;
-}
-FWL_ERR CFWL_SpinButtonImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                                 const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+void CFWL_SpinButtonImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {}
+
+void CFWL_SpinButtonImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                              const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
+
 void CFWL_SpinButtonImpDelegate::OnFocusChanged(CFWL_Message* pMsg,
                                                 FX_BOOL bSet) {
   if (bSet) {
diff --git a/xfa/fwl/basewidget/fwl_spinbuttonimp.h b/xfa/fwl/basewidget/fwl_spinbuttonimp.h
index 3f9dc77c4e..aa963c9da4 100644
--- a/xfa/fwl/basewidget/fwl_spinbuttonimp.h
+++ b/xfa/fwl/basewidget/fwl_spinbuttonimp.h
@@ -20,17 +20,17 @@ class CFWL_SpinButtonImp : public CFWL_WidgetImp, public IFWL_Timer {
   CFWL_SpinButtonImp(const CFWL_WidgetImpProperties& properties,
                      IFWL_Widget* pOuter);
   ~CFWL_SpinButtonImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  virtual FWL_ERR Update();
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error Update();
   virtual FWL_WidgetHit HitTest(FX_FLOAT fx, FX_FLOAT fy);
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
   virtual int32_t Run(FWL_HTIMER hTimer);
-  FWL_ERR EnableButton(FX_BOOL bEnable, FX_BOOL bUp = TRUE);
+  FWL_Error EnableButton(FX_BOOL bEnable, FX_BOOL bUp = TRUE);
   FX_BOOL IsButtonEnable(FX_BOOL bUp = TRUE);
 
  protected:
@@ -53,10 +53,10 @@ class CFWL_SpinButtonImp : public CFWL_WidgetImp, public IFWL_Timer {
 class CFWL_SpinButtonImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_SpinButtonImpDelegate(CFWL_SpinButtonImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnProcessEvent(CFWL_Event* pEvent) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessEvent(CFWL_Event* pEvent) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void OnFocusChanged(CFWL_Message* pMsg, FX_BOOL bSet = TRUE);
diff --git a/xfa/fwl/basewidget/fwl_tooltipctrlimp.cpp b/xfa/fwl/basewidget/fwl_tooltipctrlimp.cpp
index 0a8d343cef..f1878edee8 100644
--- a/xfa/fwl/basewidget/fwl_tooltipctrlimp.cpp
+++ b/xfa/fwl/basewidget/fwl_tooltipctrlimp.cpp
@@ -27,16 +27,21 @@ IFWL_ToolTip* IFWL_ToolTip::Create(const CFWL_WidgetImpProperties& properties,
   pToolTipImpl->SetInterface(pToolTip);
   return pToolTip;
 }
-FWL_ERR IFWL_ToolTip::SetAnchor(const CFX_RectF& rtAnchor) {
-  return static_cast<CFWL_ToolTipImp*>(GetImpl())->SetAnchor(rtAnchor);
+
+void IFWL_ToolTip::SetAnchor(const CFX_RectF& rtAnchor) {
+  static_cast<CFWL_ToolTipImp*>(GetImpl())->SetAnchor(rtAnchor);
 }
-FWL_ERR IFWL_ToolTip::Show() {
-  return static_cast<CFWL_ToolTipImp*>(GetImpl())->Show();
+
+void IFWL_ToolTip::Show() {
+  static_cast<CFWL_ToolTipImp*>(GetImpl())->Show();
 }
-FWL_ERR IFWL_ToolTip::Hide() {
-  return static_cast<CFWL_ToolTipImp*>(GetImpl())->Hide();
+
+void IFWL_ToolTip::Hide() {
+  static_cast<CFWL_ToolTipImp*>(GetImpl())->Hide();
 }
+
 IFWL_ToolTip::IFWL_ToolTip() {}
+
 CFWL_ToolTipImp::CFWL_ToolTipImp(const CFWL_WidgetImpProperties& properties,
                                  IFWL_Widget* pOuter)
     : CFWL_FormImp(properties, pOuter),
@@ -58,27 +63,27 @@ CFWL_ToolTipImp::~CFWL_ToolTipImp() {
     m_pTimer = NULL;
   }
 }
-FWL_ERR CFWL_ToolTipImp::GetClassName(CFX_WideString& wsClass) const {
+FWL_Error CFWL_ToolTipImp::GetClassName(CFX_WideString& wsClass) const {
   wsClass = FWL_CLASS_ToolTip;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 uint32_t CFWL_ToolTipImp::GetClassID() const {
   return FWL_CLASSHASH_ToolTip;
 }
-FWL_ERR CFWL_ToolTipImp::Initialize() {
+FWL_Error CFWL_ToolTipImp::Initialize() {
   m_pProperties->m_dwStyles |= FWL_WGTSTYLE_Popup;
   m_pProperties->m_dwStyles &= ~FWL_WGTSTYLE_Child;
-  if (CFWL_WidgetImp::Initialize() != FWL_ERR_Succeeded)
-    return FWL_ERR_Indefinite;
+  if (CFWL_WidgetImp::Initialize() != FWL_Error::Succeeded)
+    return FWL_Error::Indefinite;
   m_pDelegate = new CFWL_ToolTipImpDelegate(this);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ToolTipImp::Finalize() {
+FWL_Error CFWL_ToolTipImp::Finalize() {
   delete m_pDelegate;
   m_pDelegate = nullptr;
   return CFWL_WidgetImp::Finalize();
 }
-FWL_ERR CFWL_ToolTipImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
+FWL_Error CFWL_ToolTipImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   if (bAutoSize) {
     rect.Set(0, 0, 0, 0);
     if (m_pProperties->m_pThemeProvider == NULL) {
@@ -101,11 +106,11 @@ FWL_ERR CFWL_ToolTipImp::GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize) {
   } else {
     rect = m_pProperties->m_rtWidget;
   }
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ToolTipImp::Update() {
+FWL_Error CFWL_ToolTipImp::Update() {
   if (IsLocked()) {
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   }
   if (!m_pProperties->m_pThemeProvider) {
     m_pProperties->m_pThemeProvider = GetAvailableTheme();
@@ -113,9 +118,9 @@ FWL_ERR CFWL_ToolTipImp::Update() {
   UpdateTextOutStyles();
   GetClientRect(m_rtClient);
   m_rtCaption = m_rtClient;
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ToolTipImp::GetClientRect(CFX_RectF& rect) {
+FWL_Error CFWL_ToolTipImp::GetClientRect(CFX_RectF& rect) {
   FX_FLOAT x = 0;
   FX_FLOAT y = 0;
   FX_FLOAT t = 0;
@@ -131,23 +136,23 @@ FWL_ERR CFWL_ToolTipImp::GetClientRect(CFX_RectF& rect) {
   rect = m_pProperties->m_rtWidget;
   rect.Offset(-rect.left, -rect.top);
   rect.Deflate(x, t, x, y);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
-FWL_ERR CFWL_ToolTipImp::DrawWidget(CFX_Graphics* pGraphics,
-                                    const CFX_Matrix* pMatrix) {
+FWL_Error CFWL_ToolTipImp::DrawWidget(CFX_Graphics* pGraphics,
+                                      const CFX_Matrix* pMatrix) {
   IFWL_ToolTipTarget* toolTipTarget =
       CFWL_ToolTipContainer::getInstance()->GetCurrentToolTipTarget();
   if (toolTipTarget && !toolTipTarget->UseDefaultTheme()) {
     return toolTipTarget->DrawToolTip(pGraphics, pMatrix, m_pInterface);
   }
   if (!pGraphics)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   if (!m_pProperties->m_pThemeProvider)
-    return FWL_ERR_Indefinite;
+    return FWL_Error::Indefinite;
   IFWL_ThemeProvider* pTheme = m_pProperties->m_pThemeProvider;
   DrawBkground(pGraphics, pTheme, pMatrix);
   DrawText(pGraphics, pTheme, pMatrix);
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 void CFWL_ToolTipImp::DrawBkground(CFX_Graphics* pGraphics,
                                    IFWL_ThemeProvider* pTheme,
@@ -200,30 +205,29 @@ void CFWL_ToolTipImp::UpdateTextOutStyles() {
     m_dwTTOStyles &= ~FDE_TTOSTYLE_SingleLine;
   }
 }
-FWL_ERR CFWL_ToolTipImp::SetAnchor(const CFX_RectF& rtAnchor) {
+
+void CFWL_ToolTipImp::SetAnchor(const CFX_RectF& rtAnchor) {
   m_rtAnchor = rtAnchor;
-  return TRUE;
 }
-FWL_ERR CFWL_ToolTipImp::Show() {
+
+void CFWL_ToolTipImp::Show() {
   IFWL_ToolTipDP* pData =
       static_cast<IFWL_ToolTipDP*>(m_pProperties->m_pDataProvider);
   int32_t nInitDelay = pData->GetInitialDelay(m_pInterface);
-  if ((m_pProperties->m_dwStates & FWL_WGTSTATE_Invisible)) {
+  if ((m_pProperties->m_dwStates & FWL_WGTSTATE_Invisible))
     m_hTimerShow = FWL_StartTimer(&m_TimerShow, nInitDelay, FALSE);
-  }
-  return TRUE;
 }
-FWL_ERR CFWL_ToolTipImp::Hide() {
+
+void CFWL_ToolTipImp::Hide() {
   SetStates(FWL_WGTSTATE_Invisible, TRUE);
   if (m_hTimerHide) {
     FWL_StopTimer(m_hTimerHide);
-    m_hTimerHide = NULL;
+    m_hTimerHide = nullptr;
   }
   if (m_hTimerShow) {
     FWL_StopTimer(m_hTimerShow);
-    m_hTimerShow = NULL;
+    m_hTimerShow = nullptr;
   }
-  return TRUE;
 }
 
 void CFWL_ToolTipImp::SetStates(uint32_t dwStates, FX_BOOL bSet) {
@@ -284,15 +288,17 @@ int32_t CFWL_ToolTipImp::CFWL_ToolTipTimer::Run(FWL_HTIMER hTimer) {
   }
   return TRUE;
 }
+
 CFWL_ToolTipImpDelegate::CFWL_ToolTipImpDelegate(CFWL_ToolTipImp* pOwner)
     : m_pOwner(pOwner) {}
-int32_t CFWL_ToolTipImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
-  return CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
-}
-FWL_ERR CFWL_ToolTipImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {
-  return FWL_ERR_Succeeded;
+
+void CFWL_ToolTipImpDelegate::OnProcessMessage(CFWL_Message* pMessage) {
+  CFWL_WidgetImpDelegate::OnProcessMessage(pMessage);
 }
-FWL_ERR CFWL_ToolTipImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                              const CFX_Matrix* pMatrix) {
-  return m_pOwner->DrawWidget(pGraphics, pMatrix);
+
+void CFWL_ToolTipImpDelegate::OnProcessEvent(CFWL_Event* pEvent) {}
+
+void CFWL_ToolTipImpDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                           const CFX_Matrix* pMatrix) {
+  m_pOwner->DrawWidget(pGraphics, pMatrix);
 }
diff --git a/xfa/fwl/basewidget/fwl_tooltipctrlimp.h b/xfa/fwl/basewidget/fwl_tooltipctrlimp.h
index 0c053869ed..16ff424c7c 100644
--- a/xfa/fwl/basewidget/fwl_tooltipctrlimp.h
+++ b/xfa/fwl/basewidget/fwl_tooltipctrlimp.h
@@ -20,19 +20,19 @@ class CFWL_ToolTipImp : public CFWL_FormImp {
   CFWL_ToolTipImp(const CFWL_WidgetImpProperties& properties,
                   IFWL_Widget* pOuter);
   virtual ~CFWL_ToolTipImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  virtual FWL_ERR Update();
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error Update();
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
   virtual void SetStates(uint32_t dwStates, FX_BOOL bSet);
-  virtual FWL_ERR GetClientRect(CFX_RectF& rect);
-  FWL_ERR SetAnchor(const CFX_RectF& rtAnchor);
-  FWL_ERR Show();
-  FWL_ERR Hide();
+  virtual FWL_Error GetClientRect(CFX_RectF& rect);
+  void SetAnchor(const CFX_RectF& rtAnchor);
+  void Show();
+  void Hide();
 
  protected:
   void DrawBkground(CFX_Graphics* pGraphics,
@@ -68,10 +68,10 @@ class CFWL_ToolTipImp : public CFWL_FormImp {
 class CFWL_ToolTipImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_ToolTipImpDelegate(CFWL_ToolTipImp* pOwner);
-  int32_t OnProcessMessage(CFWL_Message* pMessage) override;
-  FWL_ERR OnProcessEvent(CFWL_Event* pEvent) override;
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  void OnProcessMessage(CFWL_Message* pMessage) override;
+  void OnProcessEvent(CFWL_Event* pEvent) override;
+  void OnDrawWidget(CFX_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   void OnFocusChanged(CFWL_Message* pMsg, FX_BOOL bSet = TRUE);
diff --git a/xfa/fwl/basewidget/ifwl_caret.h b/xfa/fwl/basewidget/ifwl_caret.h
index 9d0c8a70f9..c7481bdb3c 100644
--- a/xfa/fwl/basewidget/ifwl_caret.h
+++ b/xfa/fwl/basewidget/ifwl_caret.h
@@ -20,9 +20,9 @@ class IFWL_Caret : public IFWL_Widget {
                             IFWL_Widget* pOuter);
 
   void ShowCaret(FX_BOOL bFlag = TRUE);
-  FWL_ERR GetFrequency(uint32_t& elapse);
-  FWL_ERR SetFrequency(uint32_t elapse);
-  FWL_ERR SetColor(CFX_Color crFill);
+  FWL_Error GetFrequency(uint32_t& elapse);
+  FWL_Error SetFrequency(uint32_t elapse);
+  FWL_Error SetColor(CFX_Color crFill);
 
  protected:
   IFWL_Caret();
diff --git a/xfa/fwl/basewidget/ifwl_checkbox.h b/xfa/fwl/basewidget/ifwl_checkbox.h
index 0f4b42c2c8..83c0dd4724 100644
--- a/xfa/fwl/basewidget/ifwl_checkbox.h
+++ b/xfa/fwl/basewidget/ifwl_checkbox.h
@@ -59,7 +59,7 @@ class IFWL_CheckBox : public IFWL_Widget {
   static IFWL_CheckBox* Create(const CFWL_WidgetImpProperties& properties,
                                IFWL_Widget* pOuter);
   int32_t GetCheckState();
-  FWL_ERR SetCheckState(int32_t iCheck);
+  FWL_Error SetCheckState(int32_t iCheck);
 
  protected:
   IFWL_CheckBox();
diff --git a/xfa/fwl/basewidget/ifwl_combobox.h b/xfa/fwl/basewidget/ifwl_combobox.h
index b76724811b..92e213f9d0 100644
--- a/xfa/fwl/basewidget/ifwl_combobox.h
+++ b/xfa/fwl/basewidget/ifwl_combobox.h
@@ -80,22 +80,22 @@ class IFWL_ComboBox : public IFWL_Widget {
   static IFWL_ComboBox* Create(const CFWL_WidgetImpProperties& properties);
 
   int32_t GetCurSel();
-  FWL_ERR SetCurSel(int32_t iSel);
-  FWL_ERR SetEditText(const CFX_WideString& wsText);
+  FWL_Error SetCurSel(int32_t iSel);
+  FWL_Error SetEditText(const CFX_WideString& wsText);
   int32_t GetEditTextLength() const;
-  FWL_ERR GetEditText(CFX_WideString& wsText,
-                      int32_t nStart = 0,
-                      int32_t nCount = -1) const;
-  FWL_ERR SetEditSelRange(int32_t nStart, int32_t nCount = -1);
+  FWL_Error GetEditText(CFX_WideString& wsText,
+                        int32_t nStart = 0,
+                        int32_t nCount = -1) const;
+  FWL_Error SetEditSelRange(int32_t nStart, int32_t nCount = -1);
   int32_t GetEditSelRange(int32_t nIndex, int32_t& nStart);
   int32_t GetEditLimit();
-  FWL_ERR SetEditLimit(int32_t nLimit);
-  FWL_ERR EditDoClipboard(int32_t iCmd);
+  FWL_Error SetEditLimit(int32_t nLimit);
+  FWL_Error EditDoClipboard(int32_t iCmd);
   FX_BOOL EditRedo(const CFX_ByteStringC& bsRecord);
   FX_BOOL EditUndo(const CFX_ByteStringC& bsRecord);
   IFWL_ListBox* GetListBoxt();
   FX_BOOL AfterFocusShowDropList();
-  FX_ERR OpenDropDownList(FX_BOOL bActivate);
+  FWL_Error OpenDropDownList(FX_BOOL bActivate);
   FX_BOOL EditCanUndo();
   FX_BOOL EditCanRedo();
   FX_BOOL EditUndo();
@@ -109,9 +109,9 @@ class IFWL_ComboBox : public IFWL_Widget {
   FX_BOOL EditSelectAll();
   FX_BOOL EditDelete();
   FX_BOOL EditDeSelect();
-  FWL_ERR GetBBox(CFX_RectF& rect);
-  FWL_ERR EditModifyStylesEx(uint32_t dwStylesExAdded,
-                             uint32_t dwStylesExRemoved);
+  FWL_Error GetBBox(CFX_RectF& rect);
+  FWL_Error EditModifyStylesEx(uint32_t dwStylesExAdded,
+                               uint32_t dwStylesExRemoved);
 
  protected:
   IFWL_ComboBox();
diff --git a/xfa/fwl/basewidget/ifwl_datetimepicker.h b/xfa/fwl/basewidget/ifwl_datetimepicker.h
index 3d1188eead..446f988fd3 100644
--- a/xfa/fwl/basewidget/ifwl_datetimepicker.h
+++ b/xfa/fwl/basewidget/ifwl_datetimepicker.h
@@ -53,10 +53,10 @@ END_FWL_EVENT_DEF
 
 class IFWL_DateTimePickerDP : public IFWL_DataProvider {
  public:
-  virtual FWL_ERR GetToday(IFWL_Widget* pWidget,
-                           int32_t& iYear,
-                           int32_t& iMonth,
-                           int32_t& iDay) = 0;
+  virtual FWL_Error GetToday(IFWL_Widget* pWidget,
+                             int32_t& iYear,
+                             int32_t& iMonth,
+                             int32_t& iDay) = 0;
 };
 
 class IFWL_DateTimePicker : public IFWL_Widget {
@@ -64,12 +64,12 @@ class IFWL_DateTimePicker : public IFWL_Widget {
   static IFWL_DateTimePicker* Create(const CFWL_WidgetImpProperties& properties,
                                      IFWL_Widget* pOuter);
 
-  FWL_ERR GetCurSel(int32_t& iYear, int32_t& iMonth, int32_t& iDay);
-  FWL_ERR SetCurSel(int32_t iYear, int32_t iMonth, int32_t iDay);
-  FWL_ERR SetEditText(const CFX_WideString& wsText);
-  FWL_ERR GetEditText(CFX_WideString& wsText,
-                      int32_t nStart = 0,
-                      int32_t nCount = -1) const;
+  FWL_Error GetCurSel(int32_t& iYear, int32_t& iMonth, int32_t& iDay);
+  FWL_Error SetCurSel(int32_t iYear, int32_t iMonth, int32_t iDay);
+  FWL_Error SetEditText(const CFX_WideString& wsText);
+  FWL_Error GetEditText(CFX_WideString& wsText,
+                        int32_t nStart = 0,
+                        int32_t nCount = -1) const;
   int32_t CountSelRanges();
   int32_t GetSelRange(int32_t nIndex, int32_t& nStart);
   FX_BOOL CanUndo();
@@ -85,10 +85,10 @@ class IFWL_DateTimePicker : public IFWL_Widget {
   FX_BOOL SelectAll();
   FX_BOOL Delete();
   FX_BOOL DeSelect();
-  FWL_ERR GetBBox(CFX_RectF& rect);
-  FWL_ERR SetEditLimit(int32_t nLimit);
-  FWL_ERR ModifyEditStylesEx(uint32_t dwStylesExAdded,
-                             uint32_t dwStylesExRemoved);
+  FWL_Error GetBBox(CFX_RectF& rect);
+  FWL_Error SetEditLimit(int32_t nLimit);
+  FWL_Error ModifyEditStylesEx(uint32_t dwStylesExAdded,
+                               uint32_t dwStylesExRemoved);
 
  protected:
   IFWL_DateTimePicker();
diff --git a/xfa/fwl/basewidget/ifwl_edit.h b/xfa/fwl/basewidget/ifwl_edit.h
index 3b25eaf548..87f55d7d1e 100644
--- a/xfa/fwl/basewidget/ifwl_edit.h
+++ b/xfa/fwl/basewidget/ifwl_edit.h
@@ -102,30 +102,30 @@ class IFWL_Edit : public IFWL_Widget {
   static IFWL_Edit* CreateComboEdit(const CFWL_WidgetImpProperties& properties,
                                     IFWL_Widget* pOuter);
 
-  FWL_ERR SetText(const CFX_WideString& wsText);
+  FWL_Error SetText(const CFX_WideString& wsText);
   int32_t GetTextLength() const;
-  FWL_ERR GetText(CFX_WideString& wsText,
-                  int32_t nStart = 0,
-                  int32_t nCount = -1) const;
-  FWL_ERR ClearText();
+  FWL_Error GetText(CFX_WideString& wsText,
+                    int32_t nStart = 0,
+                    int32_t nCount = -1) const;
+  FWL_Error ClearText();
   int32_t GetCaretPos() const;
   int32_t SetCaretPos(int32_t nIndex, FX_BOOL bBefore = TRUE);
-  FWL_ERR AddSelRange(int32_t nStart, int32_t nCount = -1);
+  FWL_Error AddSelRange(int32_t nStart, int32_t nCount = -1);
   int32_t CountSelRanges();
   int32_t GetSelRange(int32_t nIndex, int32_t& nStart);
-  FWL_ERR ClearSelections();
+  FWL_Error ClearSelections();
   int32_t GetLimit();
-  FWL_ERR SetLimit(int32_t nLimit);
-  FWL_ERR SetAliasChar(FX_WCHAR wAlias);
-  FWL_ERR SetFormatString(const CFX_WideString& wsFormat);
-  FWL_ERR Insert(int32_t nStart, const FX_WCHAR* lpText, int32_t nLen);
-  FWL_ERR DeleteSelections();
-  FWL_ERR DeleteRange(int32_t nStart, int32_t nCount = -1);
-  FWL_ERR ReplaceSelections(const CFX_WideStringC& wsReplace);
-  FWL_ERR Replace(int32_t nStart,
-                  int32_t nLen,
-                  const CFX_WideStringC& wsReplace);
-  FWL_ERR DoClipboard(int32_t iCmd);
+  FWL_Error SetLimit(int32_t nLimit);
+  FWL_Error SetAliasChar(FX_WCHAR wAlias);
+  FWL_Error SetFormatString(const CFX_WideString& wsFormat);
+  FWL_Error Insert(int32_t nStart, const FX_WCHAR* lpText, int32_t nLen);
+  FWL_Error DeleteSelections();
+  FWL_Error DeleteRange(int32_t nStart, int32_t nCount = -1);
+  FWL_Error ReplaceSelections(const CFX_WideStringC& wsReplace);
+  FWL_Error Replace(int32_t nStart,
+                    int32_t nLen,
+                    const CFX_WideStringC& wsReplace);
+  FWL_Error DoClipboard(int32_t iCmd);
   FX_BOOL Copy(CFX_WideString& wsCopy);
   FX_BOOL Cut(CFX_WideString& wsCut);
   FX_BOOL Paste(const CFX_WideString& wsPaste);
@@ -136,11 +136,11 @@ class IFWL_Edit : public IFWL_Widget {
   FX_BOOL Redo();
   FX_BOOL CanUndo();
   FX_BOOL CanRedo();
-  FWL_ERR SetTabWidth(FX_FLOAT fTabWidth, FX_BOOL bEquidistant);
-  FWL_ERR SetOuter(IFWL_Widget* pOuter);
-  FWL_ERR SetNumberRange(int32_t iMin, int32_t iMax);
-  FWL_ERR SetBackColor(uint32_t dwColor);
-  FWL_ERR SetFont(const CFX_WideString& wsFont, FX_FLOAT fSize);
+  FWL_Error SetTabWidth(FX_FLOAT fTabWidth, FX_BOOL bEquidistant);
+  FWL_Error SetOuter(IFWL_Widget* pOuter);
+  FWL_Error SetNumberRange(int32_t iMin, int32_t iMax);
+  FWL_Error SetBackColor(uint32_t dwColor);
+  FWL_Error SetFont(const CFX_WideString& wsFont, FX_FLOAT fSize);
   void SetScrollOffset(FX_FLOAT fScrollOffset);
   FX_BOOL GetSuggestWords(CFX_PointF pointf,
                           std::vector<CFX_ByteString>& sSuggest);
diff --git a/xfa/fwl/basewidget/ifwl_listbox.h b/xfa/fwl/basewidget/ifwl_listbox.h
index d32b020810..8b1e20b28f 100644
--- a/xfa/fwl/basewidget/ifwl_listbox.h
+++ b/xfa/fwl/basewidget/ifwl_listbox.h
@@ -15,7 +15,6 @@
 #define FWL_CLASS_ListBox L"FWL_LISTBOX"
 #define FWL_CLASSHASH_ListBox 1777358317
 #define FWL_STYLEEXT_LTB_MultiSelection (1L << 0)
-#define FWL_STYLEEXT_LTB_Sort (1L << 1)
 #define FWL_STYLEEXT_LTB_ShowScrollBarAlaways (1L << 2)
 #define FWL_STYLEEXT_LTB_MultiColumn (1L << 3)
 #define FWL_STYLEEXT_LTB_LeftAlign (0L << 4)
@@ -55,36 +54,36 @@ class IFWL_ListBoxDP : public IFWL_DataProvider {
                                FWL_HLISTITEM hItem,
                                int32_t nIndex) = 0;
   virtual uint32_t GetItemStyles(IFWL_Widget* pWidget, FWL_HLISTITEM hItem) = 0;
-  virtual FWL_ERR GetItemText(IFWL_Widget* pWidget,
-                              FWL_HLISTITEM hItem,
-                              CFX_WideString& wsText) = 0;
-  virtual FWL_ERR GetItemRect(IFWL_Widget* pWidget,
-                              FWL_HLISTITEM hItem,
-                              CFX_RectF& rtItem) = 0;
+  virtual FWL_Error GetItemText(IFWL_Widget* pWidget,
+                                FWL_HLISTITEM hItem,
+                                CFX_WideString& wsText) = 0;
+  virtual FWL_Error GetItemRect(IFWL_Widget* pWidget,
+                                FWL_HLISTITEM hItem,
+                                CFX_RectF& rtItem) = 0;
   virtual void* GetItemData(IFWL_Widget* pWidget, FWL_HLISTITEM hItem) = 0;
-  virtual FWL_ERR SetItemStyles(IFWL_Widget* pWidget,
+  virtual FWL_Error SetItemStyles(IFWL_Widget* pWidget,
+                                  FWL_HLISTITEM hItem,
+                                  uint32_t dwStyle) = 0;
+  virtual FWL_Error SetItemText(IFWL_Widget* pWidget,
+                                FWL_HLISTITEM hItem,
+                                const FX_WCHAR* pszText) = 0;
+  virtual FWL_Error SetItemRect(IFWL_Widget* pWidget,
                                 FWL_HLISTITEM hItem,
-                                uint32_t dwStyle) = 0;
-  virtual FWL_ERR SetItemText(IFWL_Widget* pWidget,
-                              FWL_HLISTITEM hItem,
-                              const FX_WCHAR* pszText) = 0;
-  virtual FWL_ERR SetItemRect(IFWL_Widget* pWidget,
-                              FWL_HLISTITEM hItem,
-                              const CFX_RectF& rtItem) = 0;
+                                const CFX_RectF& rtItem) = 0;
   virtual FX_FLOAT GetItemHeight(IFWL_Widget* pWidget) = 0;
   virtual CFX_DIBitmap* GetItemIcon(IFWL_Widget* pWidget,
                                     FWL_HLISTITEM hItem) = 0;
-  virtual FWL_ERR GetItemCheckRect(IFWL_Widget* pWidget,
-                                   FWL_HLISTITEM hItem,
-                                   CFX_RectF& rtCheck) = 0;
-  virtual FWL_ERR SetItemCheckRect(IFWL_Widget* pWidget,
-                                   FWL_HLISTITEM hItem,
-                                   const CFX_RectF& rtCheck) = 0;
+  virtual FWL_Error GetItemCheckRect(IFWL_Widget* pWidget,
+                                     FWL_HLISTITEM hItem,
+                                     CFX_RectF& rtCheck) = 0;
+  virtual FWL_Error SetItemCheckRect(IFWL_Widget* pWidget,
+                                     FWL_HLISTITEM hItem,
+                                     const CFX_RectF& rtCheck) = 0;
   virtual uint32_t GetItemCheckState(IFWL_Widget* pWidget,
                                      FWL_HLISTITEM hItem) = 0;
-  virtual FWL_ERR SetItemCheckState(IFWL_Widget* pWidget,
-                                    FWL_HLISTITEM hItem,
-                                    uint32_t dwCheckState) = 0;
+  virtual FWL_Error SetItemCheckState(IFWL_Widget* pWidget,
+                                      FWL_HLISTITEM hItem,
+                                      uint32_t dwCheckState) = 0;
 };
 
 class IFWL_ListBoxCompare {
@@ -104,10 +103,9 @@ class IFWL_ListBox : public IFWL_Widget {
   int32_t CountSelItems();
   FWL_HLISTITEM GetSelItem(int32_t nIndexSel);
   int32_t GetSelIndex(int32_t nIndex);
-  FWL_ERR SetSelItem(FWL_HLISTITEM hItem, FX_BOOL bSelect = TRUE);
-  FWL_ERR GetItemText(FWL_HLISTITEM hItem, CFX_WideString& wsText);
-  FWL_ERR GetScrollPos(FX_FLOAT& fPos, FX_BOOL bVert = TRUE);
-  FWL_ERR* Sort(IFWL_ListBoxCompare* pCom);
+  FWL_Error SetSelItem(FWL_HLISTITEM hItem, FX_BOOL bSelect = TRUE);
+  FWL_Error GetItemText(FWL_HLISTITEM hItem, CFX_WideString& wsText);
+  FWL_Error GetScrollPos(FX_FLOAT& fPos, FX_BOOL bVert = TRUE);
 
  protected:
   IFWL_ListBox();
diff --git a/xfa/fwl/basewidget/ifwl_picturebox.h b/xfa/fwl/basewidget/ifwl_picturebox.h
index e663f23432..d039a8a1b2 100644
--- a/xfa/fwl/basewidget/ifwl_picturebox.h
+++ b/xfa/fwl/basewidget/ifwl_picturebox.h
@@ -39,7 +39,7 @@ class IFWL_PictureBoxDP : public IFWL_DataProvider {
   virtual CFX_DIBitmap* GetInitialPicture(IFWL_Widget* pWidget) = 0;
   virtual int32_t GetOpacity(IFWL_Widget* pWidget) = 0;
   virtual int32_t GetFlipMode(IFWL_Widget* pWidget) = 0;
-  virtual FWL_ERR GetMatrix(IFWL_Widget* pWidget, CFX_Matrix& matrix) = 0;
+  virtual FWL_Error GetMatrix(IFWL_Widget* pWidget, CFX_Matrix& matrix) = 0;
 };
 
 class IFWL_PictureBox : public IFWL_Widget {
diff --git a/xfa/fwl/basewidget/ifwl_scrollbar.h b/xfa/fwl/basewidget/ifwl_scrollbar.h
index e199713686..176b997a3d 100644
--- a/xfa/fwl/basewidget/ifwl_scrollbar.h
+++ b/xfa/fwl/basewidget/ifwl_scrollbar.h
@@ -40,16 +40,16 @@ class IFWL_ScrollBar : public IFWL_Widget {
                                 IFWL_Widget* pOuter);
 
   FX_BOOL IsVertical();
-  FWL_ERR GetRange(FX_FLOAT& fMin, FX_FLOAT& fMax);
-  FWL_ERR SetRange(FX_FLOAT fMin, FX_FLOAT fMax);
+  FWL_Error GetRange(FX_FLOAT& fMin, FX_FLOAT& fMax);
+  FWL_Error SetRange(FX_FLOAT fMin, FX_FLOAT fMax);
   FX_FLOAT GetPageSize();
-  FWL_ERR SetPageSize(FX_FLOAT fPageSize);
+  FWL_Error SetPageSize(FX_FLOAT fPageSize);
   FX_FLOAT GetStepSize();
-  FWL_ERR SetStepSize(FX_FLOAT fStepSize);
+  FWL_Error SetStepSize(FX_FLOAT fStepSize);
   FX_FLOAT GetPos();
-  FWL_ERR SetPos(FX_FLOAT fPos);
+  FWL_Error SetPos(FX_FLOAT fPos);
   FX_FLOAT GetTrackPos();
-  FWL_ERR SetTrackPos(FX_FLOAT fTrackPos);
+  FWL_Error SetTrackPos(FX_FLOAT fTrackPos);
   FX_BOOL DoScroll(uint32_t dwCode, FX_FLOAT fPos = 0.0f);
 
  protected:
diff --git a/xfa/fwl/basewidget/ifwl_spinbutton.h b/xfa/fwl/basewidget/ifwl_spinbutton.h
index 2894d08197..5f032d9e7e 100644
--- a/xfa/fwl/basewidget/ifwl_spinbutton.h
+++ b/xfa/fwl/basewidget/ifwl_spinbutton.h
@@ -22,7 +22,7 @@ class IFWL_SpinButton : public IFWL_Widget {
   static IFWL_SpinButton* Create(const CFWL_WidgetImpProperties& properties,
                                  IFWL_Widget* pOuter);
 
-  FWL_ERR EnableButton(FX_BOOL bEnable, FX_BOOL bUp = TRUE);
+  FWL_Error EnableButton(FX_BOOL bEnable, FX_BOOL bUp = TRUE);
   FX_BOOL IsButtonEnable(FX_BOOL bUp = TRUE);
 
  protected:
diff --git a/xfa/fwl/basewidget/ifwl_tooltip.h b/xfa/fwl/basewidget/ifwl_tooltip.h
index b9a07613a8..1a4280fccf 100644
--- a/xfa/fwl/basewidget/ifwl_tooltip.h
+++ b/xfa/fwl/basewidget/ifwl_tooltip.h
@@ -22,8 +22,8 @@ class IFWL_ToolTip;
 
 class IFWL_ToolTipDP : public IFWL_DataProvider {
  public:
-  virtual FWL_ERR GetCaption(IFWL_Widget* pWidget,
-                             CFX_WideString& wsCaption) = 0;
+  virtual FWL_Error GetCaption(IFWL_Widget* pWidget,
+                               CFX_WideString& wsCaption) = 0;
   virtual int32_t GetInitialDelay(IFWL_Widget* pWidget) = 0;
   virtual int32_t GetAutoPopDelay(IFWL_Widget* pWidget) = 0;
   virtual CFX_DIBitmap* GetToolTipIcon(IFWL_Widget* pWidget) = 0;
@@ -35,9 +35,9 @@ class IFWL_ToolTip : public IFWL_Form {
   static IFWL_ToolTip* Create(const CFWL_WidgetImpProperties& properties,
                               IFWL_Widget* pOuter);
 
-  FWL_ERR SetAnchor(const CFX_RectF& rtAnchor);
-  FWL_ERR Show();
-  FWL_ERR Hide();
+  void SetAnchor(const CFX_RectF& rtAnchor);
+  void Show();
+  void Hide();
 
  protected:
   IFWL_ToolTip();