Revert "Reland c91b178b07b0d - Delete dead signin code (SigninGlobalError)"
[chromium-blink-merge.git] / ash / wm / overview / window_selector.cc
blob1699ceb684874807cef86c92b179868dd404cb42
1 // Copyright 2013 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.
5 #include "ash/wm/overview/window_selector.h"
7 #include <algorithm>
8 #include <functional>
9 #include <set>
10 #include <vector>
12 #include "ash/accessibility_delegate.h"
13 #include "ash/ash_switches.h"
14 #include "ash/metrics/user_metrics_recorder.h"
15 #include "ash/root_window_controller.h"
16 #include "ash/shell.h"
17 #include "ash/shell_window_ids.h"
18 #include "ash/switchable_windows.h"
19 #include "ash/wm/mru_window_tracker.h"
20 #include "ash/wm/overview/window_grid.h"
21 #include "ash/wm/overview/window_selector_delegate.h"
22 #include "ash/wm/overview/window_selector_item.h"
23 #include "ash/wm/panels/panel_layout_manager.h"
24 #include "ash/wm/window_state.h"
25 #include "ash/wm/window_util.h"
26 #include "base/auto_reset.h"
27 #include "base/command_line.h"
28 #include "base/metrics/histogram.h"
29 #include "third_party/skia/include/core/SkPaint.h"
30 #include "third_party/skia/include/core/SkPath.h"
31 #include "ui/aura/client/focus_client.h"
32 #include "ui/aura/window.h"
33 #include "ui/aura/window_event_dispatcher.h"
34 #include "ui/aura/window_observer.h"
35 #include "ui/base/resource/resource_bundle.h"
36 #include "ui/compositor/scoped_layer_animation_settings.h"
37 #include "ui/events/event.h"
38 #include "ui/gfx/canvas.h"
39 #include "ui/gfx/screen.h"
40 #include "ui/gfx/skia_util.h"
41 #include "ui/views/border.h"
42 #include "ui/views/controls/textfield/textfield.h"
43 #include "ui/views/layout/box_layout.h"
44 #include "ui/wm/core/window_util.h"
45 #include "ui/wm/public/activation_client.h"
47 namespace ash {
49 namespace {
51 // The proportion of screen width that the text filter takes.
52 const float kTextFilterScreenProportion = 0.25;
54 // The amount of padding surrounding the text in the text filtering textbox.
55 const int kTextFilterHorizontalPadding = 8;
57 // The distance between the top of the screen and the top edge of the
58 // text filtering textbox.
59 const int kTextFilterDistanceFromTop = 32;
61 // The height of the text filtering textbox.
62 const int kTextFilterHeight = 32;
64 // The font style used for text filtering.
65 static const ::ui::ResourceBundle::FontStyle kTextFilterFontStyle =
66 ::ui::ResourceBundle::FontStyle::MediumFont;
68 // The alpha value for the background of the text filtering textbox.
69 const unsigned char kTextFilterOpacity = 180;
71 // The radius used for the rounded corners on the text filtering textbox.
72 const int kTextFilterCornerRadius = 1;
74 // A comparator for locating a grid with a given root window.
75 struct RootWindowGridComparator
76 : public std::unary_function<WindowGrid*, bool> {
77 explicit RootWindowGridComparator(const aura::Window* root_window)
78 : root_window_(root_window) {
81 bool operator()(WindowGrid* grid) const {
82 return (grid->root_window() == root_window_);
85 const aura::Window* root_window_;
88 // A comparator for locating a selectable window given a targeted window.
89 struct WindowSelectorItemTargetComparator
90 : public std::unary_function<WindowSelectorItem*, bool> {
91 explicit WindowSelectorItemTargetComparator(const aura::Window* target_window)
92 : target(target_window) {
95 bool operator()(WindowSelectorItem* window) const {
96 return window->GetWindow() == target;
99 const aura::Window* target;
102 // A comparator for locating a selector item for a given root.
103 struct WindowSelectorItemForRoot
104 : public std::unary_function<WindowSelectorItem*, bool> {
105 explicit WindowSelectorItemForRoot(const aura::Window* root)
106 : root_window(root) {
109 bool operator()(WindowSelectorItem* item) const {
110 return item->root_window() == root_window;
113 const aura::Window* root_window;
116 // A View having rounded corners and a specified background color which is
117 // only painted within the bounds defined by the rounded corners.
118 // TODO(tdanderson): This duplicates code from RoundedImageView. Refactor these
119 // classes and move into ui/views.
120 class RoundedContainerView : public views::View {
121 public:
122 RoundedContainerView(int corner_radius, SkColor background)
123 : corner_radius_(corner_radius),
124 background_(background) {
127 ~RoundedContainerView() override {}
129 void OnPaint(gfx::Canvas* canvas) override {
130 views::View::OnPaint(canvas);
132 SkScalar radius = SkIntToScalar(corner_radius_);
133 const SkScalar kRadius[8] = {radius, radius, radius, radius,
134 radius, radius, radius, radius};
135 SkPath path;
136 gfx::Rect bounds(size());
137 path.addRoundRect(gfx::RectToSkRect(bounds), kRadius);
139 SkPaint paint;
140 paint.setAntiAlias(true);
141 canvas->ClipPath(path, true);
142 canvas->DrawColor(background_);
145 private:
146 int corner_radius_;
147 SkColor background_;
149 DISALLOW_COPY_AND_ASSIGN(RoundedContainerView);
152 // Triggers a shelf visibility update on all root window controllers.
153 void UpdateShelfVisibility() {
154 Shell::RootWindowControllerList root_window_controllers =
155 Shell::GetInstance()->GetAllRootWindowControllers();
156 for (Shell::RootWindowControllerList::iterator iter =
157 root_window_controllers.begin();
158 iter != root_window_controllers.end(); ++iter) {
159 (*iter)->UpdateShelfVisibility();
163 // Initializes the text filter on the top of the main root window and requests
164 // focus on its textfield.
165 views::Widget* CreateTextFilter(views::TextfieldController* controller,
166 aura::Window* root_window) {
167 views::Widget* widget = new views::Widget;
168 views::Widget::InitParams params;
169 params.type = views::Widget::InitParams::TYPE_WINDOW_FRAMELESS;
170 params.ownership = views::Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
171 params.opacity = views::Widget::InitParams::TRANSLUCENT_WINDOW;
172 params.parent = Shell::GetContainer(root_window,
173 kShellWindowId_OverlayContainer);
174 params.accept_events = true;
175 params.bounds = gfx::Rect(
176 root_window->bounds().width() / 2 * (1 - kTextFilterScreenProportion),
177 kTextFilterDistanceFromTop,
178 root_window->bounds().width() * kTextFilterScreenProportion,
179 kTextFilterHeight);
180 widget->Init(params);
182 // Use |container| to specify the padding surrounding the text and to give
183 // the textfield rounded corners.
184 views::View* container = new RoundedContainerView(
185 kTextFilterCornerRadius, SkColorSetARGB(kTextFilterOpacity, 0, 0, 0));
186 ui::ResourceBundle& bundle = ui::ResourceBundle::GetSharedInstance();
187 int text_height = bundle.GetFontList(kTextFilterFontStyle).GetHeight();
188 DCHECK(text_height);
189 int vertical_padding = (kTextFilterHeight - text_height) / 2;
190 container->SetLayoutManager(new views::BoxLayout(views::BoxLayout::kVertical,
191 kTextFilterHorizontalPadding,
192 vertical_padding,
193 0));
195 views::Textfield* textfield = new views::Textfield;
196 textfield->set_controller(controller);
197 textfield->SetBackgroundColor(SK_ColorTRANSPARENT);
198 textfield->SetBorder(views::Border::NullBorder());
199 textfield->SetTextColor(SK_ColorWHITE);
200 textfield->SetFontList(bundle.GetFontList(kTextFilterFontStyle));
202 container->AddChildView(textfield);
203 widget->SetContentsView(container);
205 // The textfield initially contains no text, so shift its position to be
206 // outside the visible bounds of the screen.
207 gfx::Transform transform;
208 transform.Translate(0, -WindowSelector::kTextFilterBottomEdge);
209 widget->GetNativeWindow()->SetTransform(transform);
210 widget->Show();
211 textfield->RequestFocus();
213 return widget;
216 } // namespace
218 const int WindowSelector::kTextFilterBottomEdge =
219 kTextFilterDistanceFromTop + kTextFilterHeight;
221 // static
222 bool WindowSelector::IsSelectable(aura::Window* window) {
223 wm::WindowState* state = wm::GetWindowState(window);
224 if (state->GetStateType() == wm::WINDOW_STATE_TYPE_DOCKED ||
225 state->GetStateType() == wm::WINDOW_STATE_TYPE_DOCKED_MINIMIZED) {
226 return false;
228 return state->IsUserPositionable();
231 WindowSelector::WindowSelector(WindowSelectorDelegate* delegate)
232 : delegate_(delegate),
233 restore_focus_window_(aura::client::GetFocusClient(
234 Shell::GetPrimaryRootWindow())->GetFocusedWindow()),
235 ignore_activations_(false),
236 selected_grid_index_(0),
237 overview_start_time_(base::Time::Now()),
238 num_key_presses_(0),
239 num_items_(0),
240 showing_selection_widget_(false),
241 text_filter_string_length_(0),
242 num_times_textfield_cleared_(0),
243 restoring_minimized_windows_(false) {
244 DCHECK(delegate_);
247 WindowSelector::~WindowSelector() {
248 RemoveAllObservers();
251 // NOTE: The work done in Init() is not done in the constructor because it may
252 // cause other, unrelated classes, (ie PanelLayoutManager) to make indirect
253 // calls to restoring_minimized_windows() on a partially constructed object.
254 void WindowSelector::Init(const WindowList& windows) {
255 if (restore_focus_window_)
256 restore_focus_window_->AddObserver(this);
258 aura::Window::Windows root_windows = Shell::GetAllRootWindows();
259 std::sort(root_windows.begin(), root_windows.end(),
260 [](const aura::Window* a, const aura::Window* b) {
261 // Since we don't know if windows are vertically or horizontally
262 // oriented we use both x and y position. This may be confusing
263 // if you have 3 or more monitors which are not strictly
264 // horizontal or vertical but that case is not yet supported.
265 return (a->GetBoundsInScreen().x() + a->GetBoundsInScreen().y()) <
266 (b->GetBoundsInScreen().x() + b->GetBoundsInScreen().y());
269 for (aura::Window::Windows::const_iterator iter = root_windows.begin();
270 iter != root_windows.end(); iter++) {
271 // Observed switchable containers for newly created windows on all root
272 // windows.
273 for (size_t i = 0; i < kSwitchableWindowContainerIdsLength; ++i) {
274 aura::Window* container = Shell::GetContainer(*iter,
275 kSwitchableWindowContainerIds[i]);
276 container->AddObserver(this);
277 observed_windows_.insert(container);
280 // Hide the callout widgets for panels. It is safe to call this for
281 // root windows that don't contain any panel windows.
282 static_cast<PanelLayoutManager*>(
283 Shell::GetContainer(*iter, kShellWindowId_PanelContainer)
284 ->layout_manager())->SetShowCalloutWidgets(false);
286 scoped_ptr<WindowGrid> grid(new WindowGrid(*iter, windows, this));
287 if (grid->empty())
288 continue;
289 num_items_ += grid->size();
290 grid_list_.push_back(grid.Pass());
294 // The calls to WindowGrid::PrepareForOverview() and CreateTextFilter(...)
295 // requires some LayoutManagers (ie PanelLayoutManager) to perform layouts
296 // so that windows are correctly visible and properly animated in overview
297 // mode. Otherwise these layouts should be suppressed during overview mode
298 // so they don't conflict with overview mode animations. The
299 // |restoring_minimized_windows_| flag enables the PanelLayoutManager to
300 // make this decision.
301 base::AutoReset<bool> auto_restoring_minimized_windows(
302 &restoring_minimized_windows_, true);
304 // Do not call PrepareForOverview until all items are added to window_list_
305 // as we don't want to cause any window updates until all windows in
306 // overview are observed. See http://crbug.com/384495.
307 for (WindowGrid* window_grid : grid_list_) {
308 window_grid->PrepareForOverview();
309 window_grid->PositionWindows(true);
312 text_filter_widget_.reset(
313 CreateTextFilter(this, Shell::GetPrimaryRootWindow()));
316 DCHECK(!grid_list_.empty());
317 UMA_HISTOGRAM_COUNTS_100("Ash.WindowSelector.Items", num_items_);
319 Shell* shell = Shell::GetInstance();
321 shell->activation_client()->AddObserver(this);
323 shell->GetScreen()->AddObserver(this);
324 shell->metrics()->RecordUserMetricsAction(UMA_WINDOW_OVERVIEW);
325 // Send an a11y alert.
326 shell->accessibility_delegate()->TriggerAccessibilityAlert(
327 ui::A11Y_ALERT_WINDOW_OVERVIEW_MODE_ENTERED);
329 UpdateShelfVisibility();
332 // NOTE: The work done in Shutdown() is not done in the destructor because it
333 // may cause other, unrelated classes, (ie PanelLayoutManager) to make indirect
334 // calls to restoring_minimized_windows() on a partially destructed object.
335 void WindowSelector::Shutdown() {
336 ResetFocusRestoreWindow(true);
337 RemoveAllObservers();
339 aura::Window::Windows root_windows = Shell::GetAllRootWindows();
340 for (aura::Window::Windows::const_iterator iter = root_windows.begin();
341 iter != root_windows.end(); iter++) {
342 // Un-hide the callout widgets for panels. It is safe to call this for
343 // root_windows that don't contain any panel windows.
344 static_cast<PanelLayoutManager*>(
345 Shell::GetContainer(*iter, kShellWindowId_PanelContainer)
346 ->layout_manager())->SetShowCalloutWidgets(true);
349 size_t remaining_items = 0;
350 for (WindowGrid* window_grid : grid_list_) {
351 for (WindowSelectorItem* window_selector_item : window_grid->window_list())
352 window_selector_item->RestoreWindow();
353 remaining_items += window_grid->size();
356 DCHECK(num_items_ >= remaining_items);
357 UMA_HISTOGRAM_COUNTS_100("Ash.WindowSelector.OverviewClosedItems",
358 num_items_ - remaining_items);
359 UMA_HISTOGRAM_MEDIUM_TIMES("Ash.WindowSelector.TimeInOverview",
360 base::Time::Now() - overview_start_time_);
362 // Record metrics related to text filtering.
363 UMA_HISTOGRAM_COUNTS_100("Ash.WindowSelector.TextFilteringStringLength",
364 text_filter_string_length_);
365 UMA_HISTOGRAM_COUNTS_100("Ash.WindowSelector.TextFilteringTextfieldCleared",
366 num_times_textfield_cleared_);
367 if (text_filter_string_length_) {
368 UMA_HISTOGRAM_MEDIUM_TIMES(
369 "Ash.WindowSelector.TimeInOverviewWithTextFiltering",
370 base::Time::Now() - overview_start_time_);
371 UMA_HISTOGRAM_COUNTS_100(
372 "Ash.WindowSelector.ItemsWhenTextFilteringUsed",
373 remaining_items);
376 // Clearing the window list resets the ignored_by_shelf flag on the windows.
377 grid_list_.clear();
378 UpdateShelfVisibility();
381 void WindowSelector::RemoveAllObservers() {
382 Shell* shell = Shell::GetInstance();
383 for (aura::Window* window : observed_windows_)
384 window->RemoveObserver(this);
386 shell->activation_client()->RemoveObserver(this);
387 shell->GetScreen()->RemoveObserver(this);
388 if (restore_focus_window_)
389 restore_focus_window_->RemoveObserver(this);
392 void WindowSelector::CancelSelection() {
393 delegate_->OnSelectionEnded();
396 void WindowSelector::OnGridEmpty(WindowGrid* grid) {
397 ScopedVector<WindowGrid>::iterator iter =
398 std::find(grid_list_.begin(), grid_list_.end(), grid);
399 DCHECK(iter != grid_list_.end());
400 size_t index = iter - grid_list_.begin();
401 grid_list_.erase(iter);
402 if (index > 0 && selected_grid_index_ >= index) {
403 selected_grid_index_--;
404 // If the grid which became empty was the one with the selected window, we
405 // need to select a window on the newly selected grid.
406 if (selected_grid_index_ == index - 1)
407 Move(LEFT, true);
409 if (grid_list_.empty())
410 CancelSelection();
413 void WindowSelector::SelectWindow(aura::Window* window) {
414 // Record UMA_WINDOW_OVERVIEW_ACTIVE_WINDOW_CHANGED if the user is selecting
415 // a window other than the window that was active prior to entering overview
416 // mode (i.e., the window at the front of the MRU list).
417 MruWindowTracker::WindowList window_list =
418 Shell::GetInstance()->mru_window_tracker()->BuildMruWindowList();
419 if (window_list.size() > 0 && window_list[0] != window) {
420 Shell::GetInstance()->metrics()->RecordUserMetricsAction(
421 UMA_WINDOW_OVERVIEW_ACTIVE_WINDOW_CHANGED);
424 wm::GetWindowState(window)->Activate();
427 bool WindowSelector::HandleKeyEvent(views::Textfield* sender,
428 const ui::KeyEvent& key_event) {
429 if (key_event.type() != ui::ET_KEY_PRESSED)
430 return false;
432 switch (key_event.key_code()) {
433 case ui::VKEY_ESCAPE:
434 CancelSelection();
435 break;
436 case ui::VKEY_UP:
437 num_key_presses_++;
438 Move(WindowSelector::UP, true);
439 break;
440 case ui::VKEY_DOWN:
441 num_key_presses_++;
442 Move(WindowSelector::DOWN, true);
443 break;
444 case ui::VKEY_RIGHT:
445 case ui::VKEY_TAB:
446 num_key_presses_++;
447 Move(WindowSelector::RIGHT, true);
448 break;
449 case ui::VKEY_LEFT:
450 num_key_presses_++;
451 Move(WindowSelector::LEFT, true);
452 break;
453 case ui::VKEY_RETURN:
454 // Ignore if no item is selected.
455 if (!grid_list_[selected_grid_index_]->is_selecting())
456 return false;
457 UMA_HISTOGRAM_COUNTS_100("Ash.WindowSelector.ArrowKeyPresses",
458 num_key_presses_);
459 UMA_HISTOGRAM_CUSTOM_COUNTS(
460 "Ash.WindowSelector.KeyPressesOverItemsRatio",
461 (num_key_presses_ * 100) / num_items_, 1, 300, 30);
462 Shell::GetInstance()->metrics()->RecordUserMetricsAction(
463 UMA_WINDOW_OVERVIEW_ENTER_KEY);
464 SelectWindow(
465 grid_list_[selected_grid_index_]->SelectedWindow()->GetWindow());
466 break;
467 default:
468 // Not a key we are interested in, allow the textfield to handle it.
469 return false;
471 return true;
474 void WindowSelector::OnDisplayAdded(const gfx::Display& display) {
477 void WindowSelector::OnDisplayRemoved(const gfx::Display& display) {
478 // TODO(flackr): Keep window selection active on remaining displays.
479 CancelSelection();
482 void WindowSelector::OnDisplayMetricsChanged(const gfx::Display& display,
483 uint32_t metrics) {
484 PositionWindows(/* animate */ false);
485 RepositionTextFilterOnDisplayMetricsChange();
488 void WindowSelector::OnWindowAdded(aura::Window* new_window) {
489 if (!IsSelectable(new_window))
490 return;
492 for (size_t i = 0; i < kSwitchableWindowContainerIdsLength; ++i) {
493 if (new_window->parent()->id() == kSwitchableWindowContainerIds[i] &&
494 !::wm::GetTransientParent(new_window)) {
495 // The new window is in one of the switchable containers, abort overview.
496 CancelSelection();
497 return;
502 void WindowSelector::OnWindowDestroying(aura::Window* window) {
503 window->RemoveObserver(this);
504 observed_windows_.erase(window);
505 if (window == restore_focus_window_)
506 restore_focus_window_ = nullptr;
509 void WindowSelector::OnWindowActivated(
510 aura::client::ActivationChangeObserver::ActivationReason reason,
511 aura::Window* gained_active,
512 aura::Window* lost_active) {
513 if (ignore_activations_ ||
514 !gained_active ||
515 gained_active == text_filter_widget_->GetNativeWindow()) {
516 return;
519 ScopedVector<WindowGrid>::iterator grid =
520 std::find_if(grid_list_.begin(), grid_list_.end(),
521 RootWindowGridComparator(gained_active->GetRootWindow()));
522 if (grid == grid_list_.end())
523 return;
524 const std::vector<WindowSelectorItem*> windows = (*grid)->window_list();
526 ScopedVector<WindowSelectorItem>::const_iterator iter = std::find_if(
527 windows.begin(), windows.end(),
528 WindowSelectorItemTargetComparator(gained_active));
530 if (iter != windows.end())
531 (*iter)->ShowWindowOnExit();
533 // Don't restore focus on exit if a window was just activated.
534 ResetFocusRestoreWindow(false);
535 CancelSelection();
538 void WindowSelector::OnAttemptToReactivateWindow(aura::Window* request_active,
539 aura::Window* actual_active) {
540 OnWindowActivated(aura::client::ActivationChangeObserver::ActivationReason::
541 ACTIVATION_CLIENT,
542 request_active, actual_active);
545 void WindowSelector::ContentsChanged(views::Textfield* sender,
546 const base::string16& new_contents) {
547 text_filter_string_length_ = new_contents.length();
548 if (!text_filter_string_length_)
549 num_times_textfield_cleared_++;
551 bool should_show_selection_widget = !new_contents.empty();
552 if (showing_selection_widget_ != should_show_selection_widget) {
553 ui::ScopedLayerAnimationSettings animation_settings(
554 text_filter_widget_->GetNativeWindow()->layer()->GetAnimator());
555 animation_settings.SetPreemptionStrategy(
556 ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
557 animation_settings.SetTweenType(showing_selection_widget_ ?
558 gfx::Tween::FAST_OUT_LINEAR_IN : gfx::Tween::LINEAR_OUT_SLOW_IN);
560 gfx::Transform transform;
561 if (should_show_selection_widget) {
562 transform.Translate(0, 0);
563 text_filter_widget_->GetNativeWindow()->layer()->SetOpacity(1);
564 } else {
565 transform.Translate(0, -kTextFilterBottomEdge);
566 text_filter_widget_->GetNativeWindow()->layer()->SetOpacity(0);
569 text_filter_widget_->GetNativeWindow()->SetTransform(transform);
570 showing_selection_widget_ = should_show_selection_widget;
572 for (ScopedVector<WindowGrid>::iterator iter = grid_list_.begin();
573 iter != grid_list_.end(); iter++) {
574 (*iter)->FilterItems(new_contents);
577 // If the selection widget is not active, execute a Move() command so that it
578 // shows up on the first undimmed item.
579 if (grid_list_[selected_grid_index_]->is_selecting())
580 return;
581 Move(WindowSelector::RIGHT, false);
584 void WindowSelector::PositionWindows(bool animate) {
585 for (ScopedVector<WindowGrid>::iterator iter = grid_list_.begin();
586 iter != grid_list_.end(); iter++) {
587 (*iter)->PositionWindows(animate);
591 void WindowSelector::RepositionTextFilterOnDisplayMetricsChange() {
592 aura::Window* root_window = Shell::GetPrimaryRootWindow();
593 gfx::Rect rect(
594 root_window->bounds().width() / 2 * (1 - kTextFilterScreenProportion),
595 kTextFilterDistanceFromTop,
596 root_window->bounds().width() * kTextFilterScreenProportion,
597 kTextFilterHeight);
599 text_filter_widget_->SetBounds(rect);
601 gfx::Transform transform;
602 transform.Translate(0, text_filter_string_length_ == 0
603 ? -WindowSelector::kTextFilterBottomEdge
604 : 0);
605 text_filter_widget_->GetNativeWindow()->SetTransform(transform);
608 void WindowSelector::ResetFocusRestoreWindow(bool focus) {
609 if (!restore_focus_window_)
610 return;
611 if (focus) {
612 base::AutoReset<bool> restoring_focus(&ignore_activations_, true);
613 restore_focus_window_->Focus();
615 // If the window is in the observed_windows_ list it needs to continue to be
616 // observed.
617 if (observed_windows_.find(restore_focus_window_) ==
618 observed_windows_.end()) {
619 restore_focus_window_->RemoveObserver(this);
621 restore_focus_window_ = nullptr;
624 void WindowSelector::Move(Direction direction, bool animate) {
625 // Direction to move if moving past the end of a display.
626 int display_direction = (direction == RIGHT || direction == DOWN) ? 1 : -1;
628 // If this is the first move and it's going backwards, start on the last
629 // display.
630 if (display_direction == -1 && !grid_list_.empty() &&
631 !grid_list_[selected_grid_index_]->is_selecting()) {
632 selected_grid_index_ = grid_list_.size() - 1;
635 // Keep calling Move() on the grids until one of them reports no overflow or
636 // we made a full cycle on all the grids.
637 for (size_t i = 0;
638 i <= grid_list_.size() &&
639 grid_list_[selected_grid_index_]->Move(direction, animate); i++) {
640 selected_grid_index_ =
641 (selected_grid_index_ + display_direction + grid_list_.size()) %
642 grid_list_.size();
646 } // namespace ash