Animate the App List overlay when dialogs are opened

ui/app_list/views/app_list_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 "ui/app_list/views/app_list_view.h"
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/strings/string_util.h"
@@ skipping 100 matching lines @@
       : frame_(NULL),
         target_(NULL) {
   }
 
   virtual ~HideViewAnimationObserver() {
     if (target_)
       StopObservingImplicitAnimations();
   }
 
   void SetTarget(views::View* target) {
-    if (!target_)
+    if (target_)
       StopObservingImplicitAnimations();
     target_ = target;
   }
 
   void set_frame(views::BubbleFrameView* frame) { frame_ = frame; }
 
  private:
   // Overridden from ui::ImplicitAnimationObserver:
   virtual void OnImplicitAnimationsCompleted() OVERRIDE {
     if (target_) {
       target_->SetVisible(false);
       target_ = NULL;
 
       // Should update the background by invoking SchedulePaint().
-      frame_->SchedulePaint();
+      if (frame_)
+        frame_->SchedulePaint();
     }
   }
 
   views::BubbleFrameView* frame_;
   views::View* target_;
 
   DISALLOW_COPY_AND_ASSIGN(HideViewAnimationObserver);
 };
 
 ////////////////////////////////////////////////////////////////////////////////
@@ skipping 67 matching lines @@
   app_list_main_view_->Close();
   delegate_->Dismiss();
 }
 
 void AppListView::UpdateBounds() {
   SizeToContents();
 }
 
 void AppListView::SetAppListOverlayVisible(bool visible) {
   DCHECK(overlay_view_);
-  overlay_view_->SetVisible(visible);
+
+  // Display the overlay immediately so we can begin the animation.
+  overlay_view_->SetVisible(true);
+
+  ui::ScopedLayerAnimationSettings settings(
+      overlay_view_->layer()->GetAnimator());
+  settings.SetTweenType(gfx::Tween::LINEAR);
+
+  // If we're dismissing the overlay, hide the view at the end of the animation.
+  if (!visible) {
+    // Since only one animation is visible at a time, it's safe to re-use
+    // animation_observer_ here.

[calamity, 2014/08/04 06:50:17]

Call animation_observer_->set_frame_view(NULL) here.

[sashab, 2014/08/05 01:17:55]

It's not necessary (NULL is the default), but I see why you'd want to do it for
clarity. Done.

+    animation_observer_->SetTarget(overlay_view_);
+    settings.AddObserver(animation_observer_.get());
+  }
+
+  const float kOverlayFadeInMilliseconds = 125;
+  settings.SetTransitionDuration(
+      base::TimeDelta::FromMilliseconds(kOverlayFadeInMilliseconds));
+
+  const float kOverlayOpacity = 0.75f;
+  overlay_view_->layer()->SetOpacity(visible ? kOverlayOpacity : 0.0f);
 }
 
 bool AppListView::ShouldCenterWindow() const {
   return delegate_->ShouldCenterWindow();
 }
 
 gfx::Size AppListView::GetPreferredSize() const {
   return app_list_main_view_->GetPreferredSize();
 }
 
@@ skipping 124 matching lines @@
   // to be shown independently in odd situations. Explicitly hide the bubble
   // widget to ensure that any WM_WINDOWPOSCHANGED messages triggered by the
   // window manager do not have the SWP_SHOWWINDOW flag set which would cause
   // the border to be shown. See http://crbug.com/231687 .
   GetWidget()->Hide();
 #endif
 
   // To make the overlay view, construct a view with a white background, rather
   // than a white rectangle in it. This is because we need overlay_view_ to be
   // drawn to its own layer (so it appears correctly in the foreground).
-  const float kOverlayOpacity = 0.75f;
   overlay_view_ = new views::View();
   overlay_view_->SetPaintToLayer(true);
-  overlay_view_->layer()->SetOpacity(kOverlayOpacity);
   overlay_view_->SetBoundsRect(GetContentsBounds());
   overlay_view_->SetVisible(false);
+  overlay_view_->layer()->SetOpacity(0.0f);
   // On platforms that don't support a shadow, the rounded border of the app
   // list is constructed _inside_ the view, so a rectangular background goes
   // over the border in the rounded corners. To fix this, give the background a
   // corner radius 1px smaller than the outer border, so it just reaches but
   // doesn't cover it.
   const int kOverlayCornerRadius =
       GetBubbleFrameView()->bubble_border()->GetBorderCornerRadius();
   overlay_view_->set_background(new AppListOverlayBackground(
       kOverlayCornerRadius - (SupportsShadow() ? 0 : 1)));
   AddChildView(overlay_view_);
@@ skipping 177 matching lines @@
       speech_view_->layer()->SetTransform(speech_transform);
   }
 
   if (will_appear)
     speech_view_->SetVisible(true);
   else
     app_list_main_view_->SetVisible(true);
 }
 
 }  // namespace app_list