CrOS: Prevent blur from showing during hotseat animations

This disables blur during animations, which improves the performance
of hotseat animations.

Bug: 1031266
Change-Id: I6f0fc2dc4a5a8f552d244ac5bd877761261c6799
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2044766
Commit-Queue: Alex Newcomer <newcomer@chromium.org>
Reviewed-by: Alex Newcomer <newcomer@chromium.org>
Reviewed-by: Manu Cornet <manucornet@chromium.org>
Cr-Commit-Position: refs/heads/master@{#740382}

ash/shelf/hotseat_widget.cc

@@ -12,6 +12,7 @@
 #include "ash/public/cpp/shelf_config.h"
 #include "ash/public/cpp/shelf_model.h"
 #include "ash/public/cpp/wallpaper_controller_observer.h"
+#include "ash/shelf/hotseat_transition_animator.h"
 #include "ash/shelf/scrollable_shelf_view.h"
 #include "ash/shelf/shelf_layout_manager.h"
 #include "ash/shelf/shelf_navigation_widget.h"
@@ -83,7 +84,8 @@ class HotseatWindowTargeter : public aura::WindowTargeter {
 
 }  // namespace
 
-class HotseatWidget::DelegateView : public views::WidgetDelegateView,
+class HotseatWidget::DelegateView : public HotseatTransitionAnimator::Observer,
+                                    public views::WidgetDelegateView,
                                     public WallpaperControllerObserver {
  public:
   explicit DelegateView(WallpaperControllerImpl* wallpaper_controller)
@@ -102,9 +104,19 @@ class HotseatWidget::DelegateView : public views::WidgetDelegateView,
 
   void SetTranslucentBackground(const gfx::Rect& translucent_background_bounds);
 
+  // Sets whether the background should be blurred as requested by the argument,
+  // unless the feature flag is disabled or |disable_blur_for_animations_| is
+  // true, in which case this disables background blur.
+  void SetBackgroundBlur(bool enable_blur);
+
   // Updates the hotseat background when tablet mode changes.
   void OnTabletModeChanged();
 
+  // HotseatTransitionAnimator::Observer:
+  void OnHotseatTransitionAnimationStarted(HotseatState from_state,
+                                           HotseatState to_state) override;
+  void OnHotseatTransitionAnimationEnded(HotseatState from_state,
+                                         HotseatState to_state) override;
   // views::WidgetDelegateView:
   bool CanActivate() const override;
   void ReorderChildLayers(ui::Layer* parent_layer) override;
@@ -116,6 +128,10 @@ class HotseatWidget::DelegateView : public views::WidgetDelegateView,
     focus_cycler_ = focus_cycler;
   }
 
+  int background_blur() const {
+    return translucent_background_.background_blur();
+  }
+
  private:
   void SetParentLayer(ui::Layer* layer);
 
@@ -125,6 +141,8 @@ class HotseatWidget::DelegateView : public views::WidgetDelegateView,
   ScrollableShelfView* scrollable_shelf_view_ = nullptr;  // unowned.
   // The WallpaperController, responsible for providing proper colors.
   WallpaperControllerImpl* wallpaper_controller_;
+  // Blur is disabled during animations to improve performance.
+  bool blur_lock_ = false;
 
   // The most recent color that the |translucent_background_| has been animated
   // to.
@@ -158,8 +176,7 @@ void HotseatWidget::DelegateView::Init(
 void HotseatWidget::DelegateView::UpdateTranslucentBackground() {
   if (!HotseatWidget::ShouldShowHotseatBackground()) {
     translucent_background_.SetVisible(false);
-    if (features::IsBackgroundBlurEnabled())
-      translucent_background_.SetBackgroundBlur(0);
+    SetBackgroundBlur(false);
     return;
   }
 
@@ -172,6 +189,7 @@ void HotseatWidget::DelegateView::SetTranslucentBackground(
   DCHECK(HotseatWidget::ShouldShowHotseatBackground());
 
   translucent_background_.SetVisible(true);
+  SetBackgroundBlur(/*enable_blur=*/true);
 
   // Animate the bounds change if we're changing the background, or if there's
   // a change of width (for instance when dragging an app into, or out of,
@@ -200,17 +218,36 @@ void HotseatWidget::DelegateView::SetTranslucentBackground(
 
   if (translucent_background_.bounds() != background_bounds)
     translucent_background_.SetBounds(background_bounds);
+}
 
-  if (features::IsBackgroundBlurEnabled()) {
-    translucent_background_.SetBackgroundBlur(
-        ShelfConfig::Get()->shelf_blur_radius());
-  }
+void HotseatWidget::DelegateView::SetBackgroundBlur(bool enable_blur) {
+  if (!features::IsBackgroundBlurEnabled() || blur_lock_)
+    return;
+
+  const int blur_radius =
+      enable_blur ? ShelfConfig::Get()->shelf_blur_radius() : 0;
+  if (translucent_background_.background_blur() != blur_radius)
+    translucent_background_.SetBackgroundBlur(blur_radius);
 }
 
 void HotseatWidget::DelegateView::OnTabletModeChanged() {
   UpdateTranslucentBackground();
 }
 
+void HotseatWidget::DelegateView::OnHotseatTransitionAnimationStarted(
+    HotseatState from_state,
+    HotseatState to_state) {
+  SetBackgroundBlur(false);
+  blur_lock_ = true;
+}
+
+void HotseatWidget::DelegateView::OnHotseatTransitionAnimationEnded(
+    HotseatState from_state,
+    HotseatState to_state) {
+  blur_lock_ = false;
+  SetBackgroundBlur(true);
+}
+
 bool HotseatWidget::DelegateView::CanActivate() const {
   // We don't want mouse clicks to activate us, but we need to allow
   // activation when the user is using the keyboard (FocusCycler).
@@ -241,6 +278,8 @@ HotseatWidget::HotseatWidget()
 
 HotseatWidget::~HotseatWidget() {
   ShelfConfig::Get()->RemoveObserver(this);
+  shelf_->shelf_widget()->hotseat_transition_animator()->RemoveObserver(
+      delegate_view_);
 }
 
 bool HotseatWidget::ShouldShowHotseatBackground() {
@@ -279,6 +318,12 @@ void HotseatWidget::Initialize(aura::Window* container, Shelf* shelf) {
   delegate_view_->Init(scrollable_shelf_view(), GetLayer());
 }
 
+void HotseatWidget::OnHotseatTransitionAnimatorCreated(
+    HotseatTransitionAnimator* animator) {
+  shelf_->shelf_widget()->hotseat_transition_animator()->AddObserver(
+      delegate_view_);
+}
+
 void HotseatWidget::OnMouseEvent(ui::MouseEvent* event) {
   if (event->type() == ui::ET_MOUSE_PRESSED)
     keyboard::KeyboardUIController::Get()->HideKeyboardImplicitlyByUser();
@@ -408,6 +453,10 @@ ShelfView* HotseatWidget::GetShelfView() {
   return shelf_view_;
 }
 
+int HotseatWidget::GetHotseatBackgroundBlurForTest() const {
+  return delegate_view_->background_blur();
+}
+
 bool HotseatWidget::IsShowingShelfMenu() const {
   return GetShelfView()->IsShowingMenu();
 }

ash/shelf/hotseat_widget.h

@@ -21,6 +21,7 @@ class FocusCycler;
 class ScrollableShelfView;
 class Shelf;
 class ShelfView;
+class HotseatTransitionAnimator;
 
 // The hotseat widget is part of the shelf and hosts app shortcuts.
 class ASH_EXPORT HotseatWidget : public ShelfComponent,
@@ -36,6 +37,11 @@ class ASH_EXPORT HotseatWidget : public ShelfComponent,
   // Initializes the widget, sets its contents view and basic properties.
   void Initialize(aura::Window* container, Shelf* shelf);
 
+  // Initializes the animation metrics reporter responsible for recording
+  // animation performance during hotseat state changes, and attaches
+  // |delegate_view_| as an observer.
+  void OnHotseatTransitionAnimatorCreated(HotseatTransitionAnimator* animator);
+
   // views::Widget:
   void OnMouseEvent(ui::MouseEvent* event) override;
   void OnGestureEvent(ui::GestureEvent* event) override;
@@ -82,6 +88,9 @@ class ASH_EXPORT HotseatWidget : public ShelfComponent,
   ShelfView* GetShelfView();
   const ShelfView* GetShelfView() const;
 
+  // Returns the background blur of the |translucent_background_| for test.
+  int GetHotseatBackgroundBlurForTest() const;
+
   void SetState(HotseatState state);
   HotseatState state() const { return state_; }
 

ash/shelf/hotseat_widget_unittest.cc

@@ -1846,4 +1846,27 @@ TEST_P(HotseatWidgetTest, HotseatRemainsHiddenIfPopupLaunched) {
   EXPECT_EQ(HotseatState::kHidden, GetShelfLayoutManager()->hotseat_state());
 }
 
+// Tests that blur is not showing during animations.
+TEST_P(HotseatWidgetTest, NoBlurDuringAnimations) {
+  TabletModeControllerTestApi().EnterTabletMode();
+  ASSERT_EQ(
+      ShelfConfig::Get()->shelf_blur_radius(),
+      GetShelfWidget()->hotseat_widget()->GetHotseatBackgroundBlurForTest());
+  ui::ScopedAnimationDurationScaleMode regular_animations(
+      ui::ScopedAnimationDurationScaleMode::NORMAL_DURATION);
+
+  // Open a window, as the hotseat animates to kHidden, it should lose its blur.
+  std::unique_ptr<aura::Window> window =
+      AshTestBase::CreateTestWindow(gfx::Rect(0, 0, 400, 400));
+  wm::ActivateWindow(window.get());
+  EXPECT_EQ(
+      0, GetShelfWidget()->hotseat_widget()->GetHotseatBackgroundBlurForTest());
+
+  // Wait for the animation to finish, hotseat blur should return.
+  ShellTestApi().WaitForWindowFinishAnimating(window.get());
+  EXPECT_EQ(
+      ShelfConfig::Get()->shelf_blur_radius(),
+      GetShelfWidget()->hotseat_widget()->GetHotseatBackgroundBlurForTest());
+}
+
 }  // namespace ash

ash/shelf/scrollable_shelf_view.cc

@@ -504,8 +504,8 @@ ScrollableShelfView::~ScrollableShelfView() {
 void ScrollableShelfView::Init() {
   // Although there is no animation for ScrollableShelfView, a layer is still
   // needed. Otherwise, the child view without its own layer will be painted on
-  // RootView and RootView is beneath |opaque_background_| in ShelfWidget. As a
-  // result, the child view will not show.
+  // RootView which is beneath |translucent_background_| in ShelfWidget.
+  // As a result, the child view will not show.
   SetPaintToLayer();
   layer()->SetFillsBoundsOpaquely(false);
 

ash/shelf/shelf_widget.cc

@@ -582,6 +582,8 @@ void ShelfWidget::RegisterHotseatWidget(HotseatWidget* hotseat_widget) {
   delegate_view_->set_context_menu_controller(hotseat_widget->GetShelfView());
   hotseat_transition_animator_.reset(new HotseatTransitionAnimator(this));
   hotseat_transition_animator_->AddObserver(delegate_view_);
+  shelf_->hotseat_widget()->OnHotseatTransitionAnimatorCreated(
+      hotseat_transition_animator());
 }
 
 void ShelfWidget::OnTabletModeChanged() {

ash/shelf/shelf_widget.h

@@ -158,7 +158,7 @@ class ASH_EXPORT ShelfWidget : public AccessibilityObserver,
     return &background_animator_;
   }
 
-  HotseatTransitionAnimator* hotseat_transition_animator_for_testing() {
+  HotseatTransitionAnimator* hotseat_transition_animator() {
     return hotseat_transition_animator_.get();
   }
 

ash/shelf/shelf_widget_unittest.cc

@@ -417,7 +417,7 @@ TEST_F(ShelfWidgetTest, OpaqueBackgroundAndDragHandleTransition) {
 
   {
     TransitionAnimationWaiter waiter(
-        GetShelfWidget()->hotseat_transition_animator_for_testing());
+        GetShelfWidget()->hotseat_transition_animator());
     waiter.Wait();
   }