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
69
70
71
72
73
74
75
76
77
78
79
80
81
|
/*
* Copyright (C) 2008 Apple Inc. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_LIFECYCLE_OBSERVER_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_LIFECYCLE_OBSERVER_H_
#include "third_party/blink/renderer/platform/heap/handle.h"
namespace blink {
template <typename Context, typename Observer>
class LifecycleNotifier;
template <typename Context, typename Observer>
class LifecycleObserver : public GarbageCollectedMixin {
public:
void Trace(blink::Visitor* visitor) override {
visitor->Trace(lifecycle_context_);
}
Context* LifecycleContext() const { return lifecycle_context_; }
void ClearContext() { SetContext(nullptr); }
protected:
explicit LifecycleObserver(Context* context) : lifecycle_context_(nullptr) {
SetContext(context);
}
void SetContext(Context*);
private:
WeakMember<Context> lifecycle_context_;
};
template <typename Context, typename Observer>
inline void LifecycleObserver<Context, Observer>::SetContext(Context* context) {
using Notifier = LifecycleNotifier<Context, Observer>;
if (lifecycle_context_ == context)
return;
if (lifecycle_context_) {
static_cast<Notifier*>(lifecycle_context_)
->RemoveObserver(static_cast<Observer*>(this));
}
lifecycle_context_ = context;
if (lifecycle_context_) {
static_cast<Notifier*>(lifecycle_context_)
->AddObserver(static_cast<Observer*>(this));
}
}
} // namespace blink
#endif // THIRD_PARTY_BLINK_RENDERER_PLATFORM_LIFECYCLE_OBSERVER_H_
|
