Relayout windows in overview when display size changes.

ash/wm/overview/window_overview.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/wm/overview/window_overview.h"
 
 #include <algorithm>
 
 #include "ash/metrics/user_metrics_recorder.h"
 #include "ash/screen_util.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/switchable_windows.h"
 #include "ash/wm/overview/scoped_transform_overview_window.h"
 #include "ash/wm/overview/window_selector.h"
 #include "ash/wm/overview/window_selector_item.h"
 #include "base/metrics/histogram.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/aura/client/cursor_client.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/events/event.h"
+#include "ui/gfx/screen.h"
 #include "ui/views/background.h"
 #include "ui/views/widget/widget.h"
 
 namespace ash {
 
 namespace {
 
 // Conceptually the window overview is a table or grid of cells having this
 // fixed aspect ratio. The number of columns is determined by maximizing the
 // area of them based on the number of windows.
@@ skipping 90 matching lines @@
       selection_index_(0),
       single_root_window_(single_root_window),
       overview_start_time_(base::Time::Now()),
       cursor_client_(NULL) {
   Shell* shell = Shell::GetInstance();
   shell->OnOverviewModeStarting();
   for (WindowSelectorItemList::iterator iter = windows_->begin();
        iter != windows_->end(); ++iter) {
     (*iter)->PrepareForOverview();
   }
-  PositionWindows();
+  PositionWindows(/* animate */ true);
   DCHECK(!windows_->empty());
   cursor_client_ = aura::client::GetCursorClient(
       windows_->front()->GetRootWindow());
   if (cursor_client_) {
     cursor_client_->SetCursor(ui::kCursorPointer);
     cursor_client_->ShowCursor();
     // TODO(flackr): Only prevent cursor changes for windows in the overview.
     // This will be easier to do without exposing the overview mode code if the
     // cursor changes are moved to ToplevelWindowEventHandler::HandleMouseMoved
     // as suggested there.
     cursor_client_->LockCursor();
   }
   shell->PrependPreTargetHandler(this);
+  shell->GetScreen()->AddObserver(this);
   shell->metrics()->RecordUserMetricsAction(UMA_WINDOW_OVERVIEW);
   HideAndTrackNonOverviewWindows();
 }
 
 WindowOverview::~WindowOverview() {
   const aura::WindowTracker::Windows hidden_windows = hidden_windows_.windows();
   for (aura::WindowTracker::Windows::const_iterator iter =
        hidden_windows.begin(); iter != hidden_windows.end(); ++iter) {
     ui::ScopedLayerAnimationSettings settings(
         (*iter)->layer()->GetAnimator());
     settings.SetTransitionDuration(base::TimeDelta::FromMilliseconds(
         ScopedTransformOverviewWindow::kTransitionMilliseconds));
     settings.SetPreemptionStrategy(
         ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
     (*iter)->layer()->SetOpacity(1);
     (*iter)->Show();
   }
   if (cursor_client_)
     cursor_client_->UnlockCursor();
   ash::Shell* shell = ash::Shell::GetInstance();
   shell->RemovePreTargetHandler(this);
+  shell->GetScreen()->RemoveObserver(this);
   UMA_HISTOGRAM_MEDIUM_TIMES(
       "Ash.WindowSelector.TimeInOverview",
       base::Time::Now() - overview_start_time_);
   shell->OnOverviewModeEnding();
 }
 
 void WindowOverview::SetSelection(size_t index) {
   gfx::Rect target_bounds(GetSelectionBounds(index));
 
   if (selection_widget_) {
@@ skipping 55 matching lines @@
     selection_widget_->GetNativeWindow()->layer()->SetOpacity(
         kWindowOverviewSelectionOpacity);
   } else {
     InitializeSelectionWidget();
     selection_widget_->SetBounds(target_bounds);
   }
   selection_index_ = index;
 }
 
 void WindowOverview::OnWindowsChanged() {
-  PositionWindows();
+  PositionWindows(/* animate */ true);
 }
 
 void WindowOverview::MoveToSingleRootWindow(aura::Window* root_window) {
   single_root_window_ = root_window;
-  PositionWindows();
+  PositionWindows(/* animate */ true);
 }
 
 void WindowOverview::OnKeyEvent(ui::KeyEvent* event) {
   if (GetTargetedWindow(static_cast<aura::Window*>(event->target())))
     event->StopPropagation();
   if (event->type() != ui::ET_KEY_PRESSED)
     return;
 
   if (event->key_code() == ui::VKEY_ESCAPE)
     window_selector_->CancelSelection();
@@ skipping 30 matching lines @@
 
   // TODO(flackr): StopPropogation prevents generation of gesture events.
   // We should find a better way to prevent events from being delivered to
   // the window, perhaps a transparent window in front of the target window
   // or using EventClientImpl::CanProcessEventsWithinSubtree and then a tap
   // gesture could be used to activate the window.
   event->SetHandled();
   window_selector_->SelectWindow(target);
 }
 
+void WindowOverview::OnDisplayBoundsChanged(const gfx::Display& display) {
+  PositionWindows(/* animate */ false);
+}
+
+void WindowOverview::OnDisplayAdded(const gfx::Display& display) {
+}
+
+void WindowOverview::OnDisplayRemoved(const gfx::Display& display) {
+}
+
 aura::Window* WindowOverview::GetEventTarget(ui::LocatedEvent* event) {
   aura::Window* target = static_cast<aura::Window*>(event->target());
   // If the target window doesn't actually contain the event location (i.e.
   // mouse down over the window and mouse up elsewhere) then do not select the
   // window.
   if (!target->ContainsPoint(event->location()))
     return NULL;
 
   return GetTargetedWindow(target);
 }
@@ skipping 40 matching lines @@
     settings.SetPreemptionStrategy(
         ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
     (*iter)->Hide();
     // Hiding the window can result in it being destroyed.
     if (!hidden_windows_.Contains(*iter))
       continue;
     (*iter)->layer()->SetOpacity(0);
   }
 }
 
-void WindowOverview::PositionWindows() {
+void WindowOverview::PositionWindows(bool animate) {
   if (single_root_window_) {
     std::vector<WindowSelectorItem*> windows;
     for (WindowSelectorItemList::iterator iter = windows_->begin();
          iter != windows_->end(); ++iter) {
       windows.push_back(*iter);
     }
-    PositionWindowsOnRoot(single_root_window_, windows);
+    PositionWindowsOnRoot(single_root_window_, windows, animate);
   } else {
     aura::Window::Windows root_window_list = Shell::GetAllRootWindows();
     for (size_t i = 0; i < root_window_list.size(); ++i)
-      PositionWindowsFromRoot(root_window_list[i]);
+      PositionWindowsFromRoot(root_window_list[i], animate);
   }
 }
 
-void WindowOverview::PositionWindowsFromRoot(aura::Window* root_window) {
+void WindowOverview::PositionWindowsFromRoot(aura::Window* root_window,
+                                             bool animate) {
   std::vector<WindowSelectorItem*> windows;
   for (WindowSelectorItemList::iterator iter = windows_->begin();
        iter != windows_->end(); ++iter) {
     if ((*iter)->GetRootWindow() == root_window)
       windows.push_back(*iter);
   }
-  PositionWindowsOnRoot(root_window, windows);
+  PositionWindowsOnRoot(root_window, windows, animate);
 }
 
 void WindowOverview::PositionWindowsOnRoot(
     aura::Window* root_window,
-    const std::vector<WindowSelectorItem*>& windows) {
+    const std::vector<WindowSelectorItem*>& windows,
+    bool animate) {
   if (windows.empty())
     return;
 
   gfx::Size window_size;
   gfx::Rect total_bounds = ScreenUtil::ConvertRectToScreen(
       root_window,
       ScreenUtil::GetDisplayWorkAreaBoundsInParent(
           Shell::GetContainer(root_window, kShellWindowId_DefaultContainer)));
 
   // Find the minimum number of windows per row that will fit all of the
@@ skipping 16 matching lines @@
       rows * window_size.height()) / 2;
   for (size_t i = 0; i < windows.size(); ++i) {
     gfx::Transform transform;
     int column = i % columns;
     int row = i / columns;
     gfx::Rect target_bounds(window_size.width() * column + x_offset,
                             window_size.height() * row + y_offset,
                             window_size.width(),
                             window_size.height());
     target_bounds.Inset(kWindowMargin, kWindowMargin);
-    windows[i]->SetBounds(root_window, target_bounds);
+    windows[i]->SetBounds(root_window, target_bounds, animate);
   }
 }
 
 void WindowOverview::InitializeSelectionWidget() {
   selection_widget_.reset(new views::Widget);
   views::Widget::InitParams params;
   params.type = views::Widget::InitParams::TYPE_POPUP;
   params.can_activate = false;
   params.keep_on_top = false;
   params.ownership = views::Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
@@ skipping 17 matching lines @@
 }
 
 gfx::Rect WindowOverview::GetSelectionBounds(size_t index) {
   gfx::Rect bounds((*windows_)[index]->bounds());
   bounds.Inset(-kWindowOverviewSelectionPadding,
                -kWindowOverviewSelectionPadding);
   return bounds;
 }
 
 }  // namespace ash