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
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
|
// 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.
#include "components/undo/undo_manager.h"
#include <memory>
#include <utility>
#include "base/auto_reset.h"
#include "base/check_op.h"
#include "base/containers/adapters.h"
#include "base/memory/ptr_util.h"
#include "base/observer_list.h"
#include "components/strings/grit/components_strings.h"
#include "components/undo/undo_manager_observer.h"
#include "components/undo/undo_operation.h"
#include "ui/base/l10n/l10n_util.h"
namespace {
// Maximum number of changes that can be undone.
const size_t kMaxUndoGroups = 100;
} // namespace
// UndoGroup ------------------------------------------------------------------
UndoGroup::UndoGroup()
: undo_label_id_(IDS_BOOKMARK_BAR_UNDO),
redo_label_id_(IDS_BOOKMARK_BAR_REDO) {
}
UndoGroup::~UndoGroup() {
}
void UndoGroup::AddOperation(std::unique_ptr<UndoOperation> operation) {
if (operations_.empty()) {
set_undo_label_id(operation->GetUndoLabelId());
set_redo_label_id(operation->GetRedoLabelId());
}
operations_.push_back(std::move(operation));
}
void UndoGroup::Undo() {
for (const std::unique_ptr<UndoOperation>& operation :
base::Reversed(operations_))
operation->Undo();
}
// UndoManager ----------------------------------------------------------------
UndoManager::UndoManager()
: group_actions_count_(0),
undo_in_progress_action_(nullptr),
undo_suspended_count_(0),
performing_undo_(false),
performing_redo_(false) {}
UndoManager::~UndoManager() {
DCHECK_EQ(0, group_actions_count_);
DCHECK_EQ(0, undo_suspended_count_);
DCHECK(!performing_undo_);
DCHECK(!performing_redo_);
}
void UndoManager::Undo() {
Undo(&performing_undo_, &undo_actions_);
}
void UndoManager::Redo() {
Undo(&performing_redo_, &redo_actions_);
}
std::u16string UndoManager::GetUndoLabel() const {
return l10n_util::GetStringUTF16(
undo_actions_.empty() ? IDS_BOOKMARK_BAR_UNDO
: undo_actions_.back()->get_undo_label_id());
}
std::u16string UndoManager::GetRedoLabel() const {
return l10n_util::GetStringUTF16(
redo_actions_.empty() ? IDS_BOOKMARK_BAR_REDO
: redo_actions_.back()->get_redo_label_id());
}
void UndoManager::AddUndoOperation(std::unique_ptr<UndoOperation> operation) {
if (IsUndoTrakingSuspended()) {
RemoveAllOperations();
operation.reset();
return;
}
if (group_actions_count_) {
pending_grouped_action_->AddOperation(std::move(operation));
} else {
auto new_action = std::make_unique<UndoGroup>();
new_action->AddOperation(std::move(operation));
AddUndoGroup(std::move(new_action));
}
}
void UndoManager::StartGroupingActions() {
if (!group_actions_count_)
pending_grouped_action_ = std::make_unique<UndoGroup>();
++group_actions_count_;
}
void UndoManager::EndGroupingActions() {
--group_actions_count_;
if (group_actions_count_ > 0)
return;
// Check that StartGroupingActions and EndGroupingActions are paired.
DCHECK_GE(group_actions_count_, 0);
bool is_user_action = !performing_undo_ && !performing_redo_;
if (!pending_grouped_action_->undo_operations().empty()) {
AddUndoGroup(std::move(pending_grouped_action_));
} else {
// No changes were executed since we started grouping actions, so the
// pending UndoGroup should be discarded.
pending_grouped_action_.reset();
// This situation is only expected when it is a user initiated action.
// Undo/Redo should have at least one operation performed.
DCHECK(is_user_action);
}
}
void UndoManager::SuspendUndoTracking() {
++undo_suspended_count_;
}
void UndoManager::ResumeUndoTracking() {
DCHECK_GT(undo_suspended_count_, 0);
--undo_suspended_count_;
}
bool UndoManager::IsUndoTrakingSuspended() const {
return undo_suspended_count_ > 0;
}
void UndoManager::RemoveAllOperations() {
DCHECK(!group_actions_count_);
undo_actions_.clear();
redo_actions_.clear();
NotifyOnUndoManagerStateChange();
}
void UndoManager::AddObserver(UndoManagerObserver* observer) {
observers_.AddObserver(observer);
}
void UndoManager::RemoveObserver(UndoManagerObserver* observer) {
observers_.RemoveObserver(observer);
}
void UndoManager::Undo(
bool* performing_indicator,
std::vector<std::unique_ptr<UndoGroup>>* active_undo_group) {
// Check that action grouping has been correctly ended.
DCHECK(!group_actions_count_);
if (active_undo_group->empty())
return;
base::AutoReset<bool> incoming_changes(performing_indicator, true);
std::unique_ptr<UndoGroup> action = std::move(active_undo_group->back());
base::AutoReset<raw_ptr<UndoGroup>> action_context(&undo_in_progress_action_,
action.get());
active_undo_group->erase(active_undo_group->begin() +
active_undo_group->size() - 1);
StartGroupingActions();
action->Undo();
EndGroupingActions();
NotifyOnUndoManagerStateChange();
}
void UndoManager::NotifyOnUndoManagerStateChange() {
for (auto& observer : observers_)
observer.OnUndoManagerStateChange();
}
void UndoManager::AddUndoGroup(std::unique_ptr<UndoGroup> new_undo_group) {
GetActiveUndoGroup()->push_back(std::move(new_undo_group));
// User actions invalidate any available redo actions.
if (is_user_action())
redo_actions_.clear();
// Limit the number of undo levels so the undo stack does not grow unbounded.
if (GetActiveUndoGroup()->size() > kMaxUndoGroups)
GetActiveUndoGroup()->erase(GetActiveUndoGroup()->begin());
NotifyOnUndoManagerStateChange();
}
std::vector<std::unique_ptr<UndoGroup>>* UndoManager::GetActiveUndoGroup() {
return performing_undo_ ? &redo_actions_ : &undo_actions_;
}
|
