Forms: avoid the need to reload the page on every change

Add pdf_update_annot, which is called before rendering an annotation, and
checks that the annotation structure has correct information. There are
three reasons the information can be out of date.

  Attributes of a field may have been changed such that its appearance
  stream needs updating. In this case the field will have have "Dirty"
  added to its dictionary

  The mouse may have changed state over the field, and a different
  appearance stream needs selecting. The annotation structure now records
  the mouse states for which the current appearance stream is acceptable.

  The field may have changed state as recorded by its "AS" value, and a
  different appearance stream needs selecting.

2 files changed, 5 insertions, 11 deletions

diff --git a/android/jni/mupdf.c b/android/jni/mupdf.c
index 2ec02bf8..2adc3b7c 100644
--- a/android/jni/mupdf.c
+++ b/android/jni/mupdf.c
@@ -150,10 +150,10 @@ Java_com_artifex_mupdf_MuPDFCore_gotoPageInternal(JNIEnv *env, jobject thiz, int
 JNIEXPORT void JNICALL
 Java_com_artifex_mupdf_MuPDFCore_markDirtyInternal(JNIEnv *env, jobject thiz, int page)
 {
-	if (currentPage != NULL && page == pagenum)
+	if (currentPageList != NULL && page == pagenum)
 	{
-		fz_free_page(doc, currentPage);
-		currentPage = NULL;
+		fz_free_display_list(ctx, currentPageList);
+		currentPageList = NULL;
 	}
 }
 
diff --git a/android/src/com/artifex/mupdf/MuPDFCore.java b/android/src/com/artifex/mupdf/MuPDFCore.java
index f2017f77..2e0db110 100644
--- a/android/src/com/artifex/mupdf/MuPDFCore.java
+++ b/android/src/com/artifex/mupdf/MuPDFCore.java
@@ -114,12 +114,8 @@ public class MuPDFCore
 			break;
 		}
 
-		if (changed) {
-			if (page == pageNum)
-				pageNum = -1;
-
+		if (changed)
 			markDirtyInternal(page);
-		}
 
 		return new PassClickResult(changed, wtype, text);
 	}
@@ -129,10 +125,8 @@ public class MuPDFCore
 		gotoPage(page);
 		success = setFocusedWidgetTextInternal(text) != 0 ? true : false;
 
-		if (success) {
-			pageNum = -1;
+		if (success)
 			markDirtyInternal(page);
-		}
 
 		return success;
 	}