Animate the OverviewButtonTray

ash/system/tray/tray_background_view.cc

 // Copyright (c) 2012 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/system/tray/tray_background_view.h"
 
 #include "ash/ash_switches.h"
 #include "ash/root_window_controller.h"
 #include "ash/screen_util.h"
 #include "ash/shelf/shelf_layout_manager.h"
 #include "ash/shelf/shelf_widget.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/system/status_area_widget.h"
 #include "ash/system/status_area_widget_delegate.h"
 #include "ash/system/tray/system_tray.h"
 #include "ash/system/tray/tray_constants.h"
 #include "ash/system/tray/tray_event_filter.h"
 #include "ash/wm/window_animations.h"
 #include "grit/ash_resources.h"
 #include "ui/accessibility/ax_view_state.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/base/resource/resource_bundle.h"
+#include "ui/compositor/layer.h"
+#include "ui/compositor/layer_animation_element.h"
+#include "ui/compositor/scoped_layer_animation_settings.h"
+#include "ui/gfx/animation/tween.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/image/image_skia_operations.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/screen.h"
 #include "ui/gfx/skia_util.h"
+#include "ui/gfx/transform.h"
 #include "ui/views/background.h"
 #include "ui/views/layout/box_layout.h"
 
 namespace {
 
 const int kTrayBackgroundAlpha = 100;
 const int kTrayBackgroundHoverAlpha = 150;
 const SkColor kTrayBackgroundPressedColor = SkColorSetRGB(66, 129, 244);
 
 const int kAnimationDurationForPopupMS = 200;
+const int kAnimationDurationForVisibility = 250;
+const int kShowAnimationDelay = 100;

[flackr, 2014/05/07 21:32:26]

It might be worth briefly describing these parameters.

[jonross, 2014/05/08 16:44:17]

Done.

 
 }  // namespace
 
 using views::TrayBubbleView;
 
 namespace ash {
 
 // static
 const char TrayBackgroundView::kViewClassName[] = "tray/TrayBackgroundView";
 
@@ skipping 249 matching lines @@
 
   // Initially we want to paint the background, but without the hover effect.
   hide_background_animator_.SetPaintsBackground(
       true, BACKGROUND_CHANGE_IMMEDIATE);
   hover_background_animator_.SetPaintsBackground(
       false, BACKGROUND_CHANGE_IMMEDIATE);
 
   tray_container_ = new TrayContainer(shelf_alignment_);
   SetContents(tray_container_);
   tray_event_filter_.reset(new TrayEventFilter);
+
+  SetPaintToLayer(true);
+  SetFillsBoundsOpaquely(false);
 }
 
 TrayBackgroundView::~TrayBackgroundView() {
   if (GetWidget())
     GetWidget()->RemoveObserver(widget_observer_.get());
 }
 
 void TrayBackgroundView::Initialize() {
   GetWidget()->AddObserver(widget_observer_.get());
   SetTrayBorder();
 }
 
+void TrayBackgroundView::SetVisible(bool visible) {
+  if (visible == this->visible())
+    return;
+
+  if (visible) {
+    // A translation transform was applied when becoming hidden. However the
+    // alignment of the shelf can change. Reset the offscreen transform so that
+    // the animation to becoming visible reflects the changed layout.
+    HideTransformation();
+    // SetVisible(false) is defered until the animation for hiding is done.
+    // Otherwise the view is immediately hidden and the animation does not
+    // render.
+    views::View::SetVisible(visible);
+  }
+
+  layer()->GetAnimator()->StopAnimating();
+  ui::ScopedLayerAnimationSettings animation(layer()->GetAnimator());
+  animation.SetTransitionDuration(base::TimeDelta::FromMilliseconds(
+      kAnimationDurationForVisibility));
+  animation.SetPreemptionStrategy(
+      ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
+
+  if (visible) {
+    animation.SetTweenType(gfx::Tween::EASE_OUT);
+    // Show is delayed so as to allow time for other children of
+    // StatusAreaWidget to begin animating to their new positions.
+    layer()->GetAnimator()->SchedulePauseForProperties(
+        base::TimeDelta::FromMilliseconds(kShowAnimationDelay),
+        ui::LayerAnimationElement::OPACITY |
+        ui::LayerAnimationElement::TRANSFORM);
+    layer()->SetOpacity(1.0f);
+    gfx::Transform transform;
+    transform.Translate(0.0f, 0.0f);
+    layer()->SetTransform(transform);
+  } else {
+    // Listen only to the hide animation. As we cannot turn off visibility
+    // until the animation is over.
+    animation.AddObserver(this);
+    animation.SetTweenType(gfx::Tween::EASE_IN);
+    layer()->SetOpacity(0.0f);
+    layer()->SetVisible(false);
+    HideTransformation();
+  }
+}
+
 const char* TrayBackgroundView::GetClassName() const {
   return kViewClassName;
 }
 
 void TrayBackgroundView::OnMouseEntered(const ui::MouseEvent& event) {
   hovered_ = true;
 }
 
 void TrayBackgroundView::OnMouseExited(const ui::MouseEvent& event) {
   hovered_ = false;
@@ skipping 81 matching lines @@
     top_edge = 0;
     left_edge = ShelfLayoutManager::kShelfItemInset;
     bottom_edge = on_edge ? kPaddingFromEdgeOfShelf : 0;
     right_edge = kShelfSize -
         ShelfLayoutManager::kShelfItemInset - kShelfItemHeight;
   }
   SetBorder(views::Border::CreateEmptyBorder(
       top_edge, left_edge, bottom_edge, right_edge));
 }
 
+void TrayBackgroundView::OnImplicitAnimationsCompleted() {
+  views::View::SetVisible(false);
+}
+
+void TrayBackgroundView::HideTransformation() {
+  gfx::Transform transform;
+  if (shelf_alignment_ == SHELF_ALIGNMENT_BOTTOM ||
+      shelf_alignment_ == SHELF_ALIGNMENT_TOP)
+    transform.Translate(width(), 0.0f);
+  else
+    transform.Translate(0.0f, height());
+  layer()->SetTransform(transform);
+}
+
 void TrayBackgroundView::InitializeBubbleAnimations(
     views::Widget* bubble_widget) {
   wm::SetWindowVisibilityAnimationType(
       bubble_widget->GetNativeWindow(),
       wm::WINDOW_VISIBILITY_ANIMATION_TYPE_FADE);
   wm::SetWindowVisibilityAnimationTransition(
       bubble_widget->GetNativeWindow(),
       wm::ANIMATE_HIDE);
   wm::SetWindowVisibilityAnimationDuration(
       bubble_widget->GetNativeWindow(),
@@ skipping 86 matching lines @@
     background_->set_alpha(kTrayBackgroundAlpha);
   SchedulePaint();
 }
 
 void TrayBackgroundView::UpdateBubbleViewArrow(
     views::TrayBubbleView* bubble_view) {
   // Nothing to do here.
 }
 
 }  // namespace ash