blob: 99a995128492f2f52f29db73196b7bcf8cb73fa0 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
// Copyright 2016 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CORE_FXCRT_INCLUDE_CFX_OBSERVABLE_H_
#define CORE_FXCRT_INCLUDE_CFX_OBSERVABLE_H_
#include <set>
#include "core/fxcrt/include/fx_system.h"
#include "third_party/base/stl_util.h"
template <class T>
class CFX_Observable {
public:
class Observer {
public:
Observer() : m_pWatchedPtr(nullptr) {}
Observer(T** pWatchedPtr) : m_pWatchedPtr(pWatchedPtr) {
if (m_pWatchedPtr)
(*m_pWatchedPtr)->AddObserver(this);
}
Observer(const Observer& that) = delete;
~Observer() {
if (m_pWatchedPtr)
(*m_pWatchedPtr)->RemoveObserver(this);
}
void SetWatchedPtr(T** pWatchedPtr) {
if (m_pWatchedPtr)
(*m_pWatchedPtr)->RemoveObserver(this);
m_pWatchedPtr = pWatchedPtr;
if (m_pWatchedPtr)
(*m_pWatchedPtr)->AddObserver(this);
}
void OnDestroy() {
ASSERT(m_pWatchedPtr);
*m_pWatchedPtr = nullptr;
m_pWatchedPtr = nullptr;
}
Observer& operator=(const Observer& that) = delete;
private:
T** m_pWatchedPtr;
};
CFX_Observable() {}
CFX_Observable(const CFX_Observable& that) = delete;
~CFX_Observable() { NotifyObservers(); }
void AddObserver(Observer* pObserver) {
ASSERT(!pdfium::ContainsKey(m_Observers, pObserver));
m_Observers.insert(pObserver);
}
void RemoveObserver(Observer* pObserver) {
ASSERT(pdfium::ContainsKey(m_Observers, pObserver));
m_Observers.erase(pObserver);
}
void NotifyObservers() {
for (auto* pObserver : m_Observers)
pObserver->OnDestroy();
m_Observers.clear();
}
CFX_Observable& operator=(const CFX_Observable& that) = delete;
private:
std::set<Observer*> m_Observers;
};
#endif // CORE_FXCRT_INCLUDE_CFX_OBSERVABLE_H_
|
