1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "ui/base/models/list_selection_model.h"
6
7 #include <algorithm>
8 #include <valarray>
9
10 #include "base/logging.h"
11
12 namespace ui {
13
14 // static
15 const int ListSelectionModel::kUnselectedIndex = -1;
16
IncrementFromImpl(int index,int * value)17 static void IncrementFromImpl(int index, int* value) {
18 if (*value >= index)
19 (*value)++;
20 }
21
DecrementFromImpl(int index,int * value)22 static bool DecrementFromImpl(int index, int* value) {
23 if (*value == index) {
24 *value = ListSelectionModel::kUnselectedIndex;
25 return true;
26 }
27 if (*value > index)
28 (*value)--;
29 return false;
30 }
31
ListSelectionModel()32 ListSelectionModel::ListSelectionModel()
33 : active_(kUnselectedIndex),
34 anchor_(kUnselectedIndex) {
35 }
36
~ListSelectionModel()37 ListSelectionModel::~ListSelectionModel() {
38 }
39
IncrementFrom(int index)40 void ListSelectionModel::IncrementFrom(int index) {
41 // Shift the selection to account for the newly inserted tab.
42 for (SelectedIndices::iterator i = selected_indices_.begin();
43 i != selected_indices_.end(); ++i) {
44 IncrementFromImpl(index, &(*i));
45 }
46 IncrementFromImpl(index, &anchor_);
47 IncrementFromImpl(index, &active_);
48 }
49
DecrementFrom(int index)50 void ListSelectionModel::DecrementFrom(int index) {
51 for (SelectedIndices::iterator i = selected_indices_.begin();
52 i != selected_indices_.end(); ) {
53 if (DecrementFromImpl(index, &(*i)))
54 i = selected_indices_.erase(i);
55 else
56 ++i;
57 }
58 DecrementFromImpl(index, &anchor_);
59 DecrementFromImpl(index, &active_);
60 }
61
SetSelectedIndex(int index)62 void ListSelectionModel::SetSelectedIndex(int index) {
63 anchor_ = active_ = index;
64 selected_indices_.clear();
65 if (index != kUnselectedIndex)
66 selected_indices_.push_back(index);
67 }
68
IsSelected(int index) const69 bool ListSelectionModel::IsSelected(int index) const {
70 return std::find(selected_indices_.begin(), selected_indices_.end(), index) !=
71 selected_indices_.end();
72 }
73
AddIndexToSelection(int index)74 void ListSelectionModel::AddIndexToSelection(int index) {
75 if (!IsSelected(index)) {
76 selected_indices_.push_back(index);
77 std::sort(selected_indices_.begin(), selected_indices_.end());
78 }
79 }
80
RemoveIndexFromSelection(int index)81 void ListSelectionModel::RemoveIndexFromSelection(int index) {
82 SelectedIndices::iterator i = std::find(selected_indices_.begin(),
83 selected_indices_.end(), index);
84 if (i != selected_indices_.end())
85 selected_indices_.erase(i);
86 }
87
SetSelectionFromAnchorTo(int index)88 void ListSelectionModel::SetSelectionFromAnchorTo(int index) {
89 if (anchor_ == kUnselectedIndex) {
90 SetSelectedIndex(index);
91 } else {
92 int delta = std::abs(index - anchor_);
93 SelectedIndices new_selection(delta + 1, 0);
94 for (int i = 0, min = std::min(index, anchor_); i <= delta; ++i)
95 new_selection[i] = i + min;
96 selected_indices_.swap(new_selection);
97 active_ = index;
98 }
99 }
100
AddSelectionFromAnchorTo(int index)101 void ListSelectionModel::AddSelectionFromAnchorTo(int index) {
102 if (anchor_ == kUnselectedIndex) {
103 SetSelectedIndex(index);
104 } else {
105 for (int i = std::min(index, anchor_), end = std::max(index, anchor_);
106 i <= end; ++i) {
107 if (!IsSelected(i))
108 selected_indices_.push_back(i);
109 }
110 std::sort(selected_indices_.begin(), selected_indices_.end());
111 active_ = index;
112 }
113 }
114
Move(int from,int to)115 void ListSelectionModel::Move(int from, int to) {
116 DCHECK_NE(to, from);
117 bool was_anchor = from == anchor_;
118 bool was_active = from == active_;
119 bool was_selected = IsSelected(from);
120 if (to < from) {
121 IncrementFrom(to);
122 DecrementFrom(from + 1);
123 } else {
124 DecrementFrom(from);
125 IncrementFrom(to);
126 }
127 if (was_active)
128 active_ = to;
129 if (was_anchor)
130 anchor_ = to;
131 if (was_selected)
132 AddIndexToSelection(to);
133 }
134
Clear()135 void ListSelectionModel::Clear() {
136 anchor_ = active_ = kUnselectedIndex;
137 SelectedIndices empty_selection;
138 selected_indices_.swap(empty_selection);
139 }
140
Copy(const ListSelectionModel & source)141 void ListSelectionModel::Copy(const ListSelectionModel& source) {
142 selected_indices_ = source.selected_indices_;
143 active_ = source.active_;
144 anchor_ = source.anchor_;
145 }
146
Equals(const ListSelectionModel & rhs) const147 bool ListSelectionModel::Equals(const ListSelectionModel& rhs) const {
148 return active_ == rhs.active() &&
149 anchor_ == rhs.anchor() &&
150 selected_indices() == rhs.selected_indices();
151 }
152
153 } // namespace ui
154