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
|
// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef UI_EVENTS_EVENT_TARGET_ITERATOR_H_
#define UI_EVENTS_EVENT_TARGET_ITERATOR_H_
#include <memory>
#include <vector>
namespace ui {
class EventTarget;
// An interface that allows iterating over a set of EventTargets.
class EventTargetIterator {
public:
virtual ~EventTargetIterator() {}
virtual EventTarget* GetNextTarget() = 0;
};
// Provides EventTargetIterator implementations for iterating over a list of
// EventTargets. The list is iterated in the reverse order, since typically the
// EventTargets are maintained in increasing z-order in the lists.
template <typename T>
class EventTargetIteratorPtrImpl : public EventTargetIterator {
public:
explicit EventTargetIteratorPtrImpl(
const std::vector<raw_ptr<T, VectorExperimental>>& children)
: begin_(children.rbegin()), end_(children.rend()) {}
~EventTargetIteratorPtrImpl() override {}
EventTarget* GetNextTarget() override {
if (begin_ == end_)
return nullptr;
EventTarget* target = *(begin_);
++begin_;
return target;
}
private:
typename std::vector<raw_ptr<T, VectorExperimental>>::const_reverse_iterator
begin_;
typename std::vector<raw_ptr<T, VectorExperimental>>::const_reverse_iterator
end_;
};
template <typename T>
class EventTargetIteratorUniquePtrImpl : public EventTargetIterator {
public:
explicit EventTargetIteratorUniquePtrImpl(
const std::vector<std::unique_ptr<T>>& children)
: begin_(children.rbegin()), end_(children.rend()) {}
~EventTargetIteratorUniquePtrImpl() override {}
EventTarget* GetNextTarget() override {
if (begin_ == end_)
return nullptr;
EventTarget* target = begin_->get();
++begin_;
return target;
}
private:
typename std::vector<std::unique_ptr<T>>::const_reverse_iterator begin_;
typename std::vector<std::unique_ptr<T>>::const_reverse_iterator end_;
};
} // namespace ui
#endif // UI_EVENTS_EVENT_TARGET_ITERATOR_H_
|
