Do not do animation when entering overview because of window dragging.

If overview mode is opened behind the current dragged window, we should
not do the animation when entering overview.

Bug: 823769
Test: None
Change-Id: I1d89bcdc27ea784449698183e026aa63f1c2cf2c
Reviewed-on: https://chromium-review.googlesource.com/1157289
Commit-Queue: Xiaoqian Dai <xdai@chromium.org>
Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#579877}

ash/wm/overview/window_grid.cc

@@ -177,9 +177,11 @@ class NewSelectorItemView : public views::View {
 };
 
 // Creates |new_selector_item_widget_|. It's created when a window (not from
-// overview) is dragged around and destroyed when the drag ends.
+// overview) is dragged around and destroyed when the drag ends. If |animate|
+// is true, do the opacity animation for the new selector item.
 std::unique_ptr<views::Widget> CreateNewSelectorItemWidget(
-    aura::Window* dragged_window) {
+    aura::Window* dragged_window,
+    bool animate) {
   views::Widget::InitParams params;
   params.type = views::Widget::InitParams::TYPE_WINDOW_FRAMELESS;
   params.ownership = views::Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
@@ -197,14 +199,16 @@ std::unique_ptr<views::Widget> CreateNewSelectorItemWidget(
   widget->SetContentsView(new NewSelectorItemView());
   widget->Show();
 
-  widget->SetOpacity(0.f);
-  ui::ScopedLayerAnimationSettings animation_settings(
-      widget->GetNativeWindow()->layer()->GetAnimator());
-  animation_settings.SetTransitionDuration(base::TimeDelta::FromMilliseconds(
-      kNewSelectorItemTransitionMilliseconds));
-  animation_settings.SetTweenType(gfx::Tween::EASE_IN);
-  animation_settings.SetPreemptionStrategy(
-      ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
+  if (animate) {
+    widget->SetOpacity(0.f);
+    ui::ScopedLayerAnimationSettings animation_settings(
+        widget->GetNativeWindow()->layer()->GetAnimator());
+    animation_settings.SetTransitionDuration(base::TimeDelta::FromMilliseconds(
+        kNewSelectorItemTransitionMilliseconds));
+    animation_settings.SetTweenType(gfx::Tween::EASE_IN);
+    animation_settings.SetPreemptionStrategy(
+        ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
+  }
   widget->SetOpacity(1.f);
   return widget;
 }
@@ -476,7 +480,7 @@ WindowSelectorItem* WindowGrid::GetWindowSelectorItemContaining(
   return nullptr;
 }
 
-void WindowGrid::AddItem(aura::Window* window, bool reposition) {
+void WindowGrid::AddItem(aura::Window* window, bool reposition, bool animate) {
   DCHECK(!GetWindowSelectorItemContaining(window));
 
   window_observer_.Add(window);
@@ -486,7 +490,7 @@ void WindowGrid::AddItem(aura::Window* window, bool reposition) {
   window_list_.back()->PrepareForOverview();
 
   if (reposition)
-    PositionWindows(/*animate=*/true);
+    PositionWindows(animate);
 }
 
 void WindowGrid::RemoveItem(WindowSelectorItem* selector_item,
@@ -577,12 +581,14 @@ void WindowGrid::OnSelectorItemDragEnded() {
     window_selector_item->OnSelectorItemDragEnded();
 }
 
-void WindowGrid::OnWindowDragStarted(aura::Window* dragged_window) {
+void WindowGrid::OnWindowDragStarted(aura::Window* dragged_window,
+                                     bool animate) {
   DCHECK_EQ(dragged_window->GetRootWindow(), root_window_);
   DCHECK(!new_selector_item_widget_);
-  new_selector_item_widget_ = CreateNewSelectorItemWidget(dragged_window);
+  new_selector_item_widget_ =
+      CreateNewSelectorItemWidget(dragged_window, animate);
   window_selector_->AddItem(new_selector_item_widget_->GetNativeWindow(),
-                            /*reposition=*/true);
+                            /*reposition=*/true, animate);
 
   // Stack the newly added window item below |dragged_window|.
   DCHECK_EQ(dragged_window->parent(),
@@ -664,8 +670,10 @@ void WindowGrid::OnWindowDragEnded(aura::Window* dragged_window,
   // add it to overview without repositioning the grid. It will be done at the
   // end of this function.
   if (SelectedWindow()) {
-    if (IsNewSelectorItemWindow(SelectedWindow()->GetWindow()))
-      window_selector_->AddItem(dragged_window, /*reposition=*/false);
+    if (IsNewSelectorItemWindow(SelectedWindow()->GetWindow())) {
+      window_selector_->AddItem(dragged_window, /*reposition=*/false,
+                                /*animate=*/false);
+    }
     SelectedWindow()->set_selected(false);
     selection_widget_.reset();
   }

ash/wm/overview/window_grid.h

@@ -92,8 +92,9 @@ class ASH_EXPORT WindowGrid : public aura::WindowObserver,
 
   // Adds |window| to the grid. Intended to be used by split view. |window|
   // cannot already be on the grid. If |reposition| is true, reposition all
-  // window items in the grid after adding the item.
-  void AddItem(aura::Window* window, bool reposition);
+  // window items in the grid after adding the item. If |animate| is true,
+  // reposition with animation.
+  void AddItem(aura::Window* window, bool reposition, bool animate);
 
   // Removes |selector_item| from the grid. If |reprosition| is ture, reposition
   // all window items in the grid after removing the item.
@@ -131,7 +132,7 @@ class ASH_EXPORT WindowGrid : public aura::WindowObserver,
 
   // Called when a window's tab(s) start/continue/end being dragged around in
   // WindowGrid.
-  void OnWindowDragStarted(aura::Window* dragged_window);
+  void OnWindowDragStarted(aura::Window* dragged_window, bool animate);
   void OnWindowDragContinued(aura::Window* dragged_window,
                              const gfx::Point& location_in_screen,
                              IndicatorState indicator_state);
@@ -142,22 +143,6 @@ class ASH_EXPORT WindowGrid : public aura::WindowObserver,
   // item.
   bool IsNewSelectorItemWindow(aura::Window* window) const;
 
-  // Returns true if the grid has no more windows.
-  bool empty() const { return window_list_.empty(); }
-
-  // Returns how many window selector items are in the grid.
-  size_t size() const { return window_list_.size(); }
-
-  // Returns true if the selection widget is active.
-  bool is_selecting() const { return selection_widget_ != nullptr; }
-
-  // Returns the root window in which the grid displays the windows.
-  const aura::Window* root_window() const { return root_window_; }
-
-  const std::vector<std::unique_ptr<WindowSelectorItem>>& window_list() const {
-    return window_list_;
-  }
-
   // aura::WindowObserver:
   void OnWindowDestroying(aura::Window* window) override;
   // TODO(flackr): Handle window bounds changed in WindowSelectorItem.
@@ -174,22 +159,6 @@ class ASH_EXPORT WindowGrid : public aura::WindowObserver,
 
   gfx::Rect GetNoItemsIndicatorLabelBoundsForTesting() const;
 
-  WindowSelector* window_selector() { return window_selector_; }
-
-  void set_window_animation_observer(
-      base::WeakPtr<OverviewWindowAnimationObserver> observer) {
-    window_animation_observer_ = observer;
-  }
-  base::WeakPtr<OverviewWindowAnimationObserver> window_animation_observer() {
-    return window_animation_observer_;
-  }
-
-  const gfx::Rect bounds() const { return bounds_; }
-
-  views::Widget* new_selector_item_widget_for_testing() {
-    return new_selector_item_widget_.get();
-  }
-
   // Sets |should_animate_when_entering_| and |should_animate_when_exiting_|
   // of the selector items of the windows based on where the first MRU window
   // covering the available workspace is found. Also sets the
@@ -221,6 +190,38 @@ class ASH_EXPORT WindowGrid : public aura::WindowObserver,
   // Clears |nudge_data_|.
   void EndNudge();
 
+  // Returns true if the grid has no more windows.
+  bool empty() const { return window_list_.empty(); }
+
+  // Returns how many window selector items are in the grid.
+  size_t size() const { return window_list_.size(); }
+
+  // Returns true if the selection widget is active.
+  bool is_selecting() const { return selection_widget_ != nullptr; }
+
+  // Returns the root window in which the grid displays the windows.
+  const aura::Window* root_window() const { return root_window_; }
+
+  const std::vector<std::unique_ptr<WindowSelectorItem>>& window_list() const {
+    return window_list_;
+  }
+
+  WindowSelector* window_selector() { return window_selector_; }
+
+  void set_window_animation_observer(
+      base::WeakPtr<OverviewWindowAnimationObserver> observer) {
+    window_animation_observer_ = observer;
+  }
+  base::WeakPtr<OverviewWindowAnimationObserver> window_animation_observer() {
+    return window_animation_observer_;
+  }
+
+  const gfx::Rect bounds() const { return bounds_; }
+
+  views::Widget* new_selector_item_widget_for_testing() {
+    return new_selector_item_widget_.get();
+  }
+
  private:
   class ShieldView;
   friend class WindowSelectorTest;

ash/wm/overview/window_selector.cc

@@ -206,6 +206,20 @@ views::Widget* CreateTextFilter(views::TextfieldController* controller,
   return widget;
 }
 
+// Gets the window that's currently being dragged in |root_window|. Returns
+// nullptr if there is no such window.
+aura::Window* GetDraggedWindow(
+    const aura::Window* root_window,
+    const std::vector<aura::Window*>& mru_window_list) {
+  for (auto* window : mru_window_list) {
+    if (wm::GetWindowState(window)->is_dragged() &&
+        window->GetRootWindow() == root_window) {
+      return window;
+    }
+  }
+  return nullptr;
+}
+
 }  // namespace
 
 // static
@@ -286,15 +300,27 @@ void WindowSelector::Init(const WindowList& windows,
     base::AutoReset<bool> auto_restoring_minimized_windows(
         &restoring_minimized_windows_, true);
 
+    WindowList mru_window_list =
+        Shell::Get()->mru_window_tracker()->BuildMruWindowList();
+
     // Do not call PrepareForOverview until all items are added to window_list_
     // as we don't want to cause any window updates until all windows in
     // overview are observed. See http://crbug.com/384495.
     for (std::unique_ptr<WindowGrid>& window_grid : grid_list_) {
-      window_grid->SetWindowListAnimationStates(/*selected_item=*/nullptr,
-                                                OverviewTransition::kEnter);
       window_grid->PrepareForOverview();
-      window_grid->PositionWindows(/*animate=*/true, /*ignore_item=*/nullptr,
-                                   OverviewTransition::kEnter);
+
+      // Check if there is any window that's being dragged in the grid. If so,
+      // do not do the animation when entering overview.
+      aura::Window* dragged_window =
+          GetDraggedWindow(window_grid->root_window(), mru_window_list);
+      if (dragged_window) {
+        window_grid->PositionWindows(/*animate=*/false);
+      } else {
+        window_grid->SetWindowListAnimationStates(/*selected_item=*/nullptr,
+                                                  OverviewTransition::kEnter);
+        window_grid->PositionWindows(/*animate=*/true, /*ignore_item=*/nullptr,
+                                     OverviewTransition::kEnter);
+      }
     }
 
     // Image used for text filter textfield.
@@ -519,13 +545,15 @@ WindowGrid* WindowSelector::GetGridWithRootWindow(aura::Window* root_window) {
   return nullptr;
 }
 
-void WindowSelector::AddItem(aura::Window* window, bool reposition) {
+void WindowSelector::AddItem(aura::Window* window,
+                             bool reposition,
+                             bool animate) {
   // Early exit if a grid already contains |window|.
   WindowGrid* grid = GetGridWithRootWindow(window->GetRootWindow());
   if (!grid || grid->GetWindowSelectorItemContaining(window))
     return;
 
-  grid->AddItem(window, reposition);
+  grid->AddItem(window, reposition, animate);
   ++num_items_;
 
   // Transfer focus from |window| to the text widget, to match the behavior of
@@ -605,12 +633,13 @@ void WindowSelector::ResetDraggedWindowGesture() {
   window_drag_controller_->ResetGesture();
 }
 
-void WindowSelector::OnWindowDragStarted(aura::Window* dragged_window) {
+void WindowSelector::OnWindowDragStarted(aura::Window* dragged_window,
+                                         bool animate) {
   WindowGrid* target_grid =
       GetGridWithRootWindow(dragged_window->GetRootWindow());
   if (!target_grid)
     return;
-  target_grid->OnWindowDragStarted(dragged_window);
+  target_grid->OnWindowDragStarted(dragged_window, animate);
 }
 
 void WindowSelector::OnWindowDragContinued(aura::Window* dragged_window,

ash/wm/overview/window_selector.h

@@ -110,14 +110,15 @@ class ASH_EXPORT WindowSelector : public display::DisplayObserver,
 
   // Add |window| to the grid in |grid_list_| with the same root window. Does
   // nothing if the grid already contains |window|. And if |reposition| is true,
-  // re-position all windows in the target window grid. This may be called in
-  // two scenarioes: 1) when a item in split view mode was previously snapped
-  // but should now be returned to the window grid (e.g. split view divider
-  // dragged to either edge, or a window is snapped to a postion that already
-  // has a snapped window); 2) when a window (not from overview) is dragged
-  // while overview is open and the window is dropped on the new selector item,
-  // the dragged window is then added to the overview.
-  void AddItem(aura::Window* window, bool reposition);
+  // re-position all windows in the target window grid. If |animate| is true,
+  // re-position with animation. This function may be called in two scenarioes:
+  // 1) when a item in split view mode was previously snapped but should now be
+  // returned to the window grid (e.g. split view divider dragged to either
+  // edge, or a window is snapped to a postion that already has a snapped
+  // window); 2) when a window (not from overview) is dragged while overview is
+  // open and the window is dropped on the new selector item, the dragged window
+  // is then added to the overview.
+  void AddItem(aura::Window* window, bool reposition, bool animate);
 
   // Removes the window selector item from the overview window grid. And if
   // |reposition| is true, re-position all windows in the target window grid.
@@ -144,7 +145,7 @@ class ASH_EXPORT WindowSelector : public display::DisplayObserver,
   // Called when a window's tab(s) start/continue/end being dragged around if
   // overview mode is active.
   // TODO(xdai): Currently it doesn't work for multi-display scenario.
-  void OnWindowDragStarted(aura::Window* dragged_window);
+  void OnWindowDragStarted(aura::Window* dragged_window, bool animate);
   void OnWindowDragContinued(aura::Window* dragged_window,
                              const gfx::Point& location_in_screen,
                              IndicatorState indicator_state);

ash/wm/splitview/split_view_controller.cc

@@ -1414,7 +1414,7 @@ void SplitViewController::InsertWindowToOverview(aura::Window* window) {
   if (!window || !Shell::Get()->window_selector_controller()->IsSelecting())
     return;
   Shell::Get()->window_selector_controller()->window_selector()->AddItem(
-      window, /*reposition=*/true);
+      window, /*reposition=*/true, /*animate=*/true);
 }
 
 void SplitViewController::StartOverview() {

ash/wm/tablet_mode/tablet_mode_app_window_drag_controller.cc

@@ -117,7 +117,8 @@ void TabletModeAppWindowDragController::EndWindowDrag(
   if (event->type() == ui::ET_SCROLL_FLING_START &&
       event->details().velocity_y() > kFlingToOverviewThreshold) {
     Shell::Get()->window_selector_controller()->window_selector()->AddItem(
-        drag_delegate_->dragged_window(), /*reposition=*/true);
+        drag_delegate_->dragged_window(), /*reposition=*/true,
+        /*animate=*/true);
   }
   drag_delegate_->EndWindowDrag(result, location_in_screen);
 }

ash/wm/tablet_mode/tablet_mode_window_drag_delegate.cc

@@ -54,17 +54,24 @@ void TabletModeWindowDragDelegate::StartWindowDrag(
   original_backdrop_mode_ = dragged_window_->GetProperty(kBackdropWindowMode);
   dragged_window_->SetProperty(kBackdropWindowMode,
                                BackdropWindowMode::kDisabled);
+
+  WindowSelectorController* controller =
+      Shell::Get()->window_selector_controller();
+  bool was_overview_open = controller->IsSelecting();
+
+  // If the dragged window is one of the snapped windows, SplitViewController
+  // might open overview in the dragged window side of the screen.
   split_view_controller_->OnWindowDragStarted(dragged_window_);
 
-  if (ShouldOpenOverviewWhenDragStarts()) {
-    WindowSelectorController* controller =
-        Shell::Get()->window_selector_controller();
-    if (!controller->IsSelecting())
-      controller->ToggleOverview();
-  }
+  if (ShouldOpenOverviewWhenDragStarts() && !controller->IsSelecting())
+    controller->ToggleOverview();
 
-  if (GetWindowSelector())
-    GetWindowSelector()->OnWindowDragStarted(dragged_window_);
+  if (controller->IsSelecting()) {
+    // Only do animation if overview was open before the drag started. If the
+    // overview is opened because of the window drag, do not do animation.
+    GetWindowSelector()->OnWindowDragStarted(dragged_window_,
+                                             /*animate=*/was_overview_open);
+  }
 }
 
 void TabletModeWindowDragDelegate::ContinueWindowDrag(