Implement animation UI for opening/closing an app list folder.

ui/app_list/views/app_list_folder_view.h

 // 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.
 
 #ifndef UI_APP_LIST_VIEWS_APP_LIST_FOLDER_VIEW_H_
 #define UI_APP_LIST_VIEWS_APP_LIST_FOLDER_VIEW_H_
 
 #include "ui/app_list/views/folder_header_view.h"
 #include "ui/app_list/views/folder_header_view_delegate.h"
+#include "ui/compositor/layer_animation_observer.h"
 #include "ui/views/controls/button/button.h"
 #include "ui/views/view.h"
 
 namespace content {
 class WebContents;
 }
 
 namespace views {
 class ViewModel;
 }
 
 namespace app_list {
 
 class AppsContainerView;
 class AppsGridView;
 class AppListFolderItem;
 class AppListMainView;
 class AppListModel;
 class FolderHeaderView;
 class PaginationModel;
 
 class AppListFolderView : public views::View,
-                          public FolderHeaderViewDelegate {
+                          public FolderHeaderViewDelegate,
+                          public ui::ImplicitAnimationObserver {
  public:
   AppListFolderView(AppsContainerView* container_view,
                     AppListModel* model,
                     AppListMainView* app_list_main_view,
                     content::WebContents* start_page_contents);
   virtual ~AppListFolderView();
 
   void SetAppListFolderItem(AppListFolderItem* folder);
 
-  // Overridden from views::View:
+  // Schedules animation to show or hide the view.

[xiyuan, 2014/01/16 01:46:48]

nit: Schedules _an_ animation

[jennyz, 2014/01/16 17:49:52]

Done.

+  void ScheduleAnimationToShow(bool show);

[xiyuan, 2014/01/16 01:46:48]

nit: ScheduleAnimationToShow makes reader think it is runs animation for showing
the content but it is actually both ways and controlled by |show|. Can we get a
better name? Maybe ScheduleShowHideAnimation?

[jennyz, 2014/01/16 17:49:52]

Done.

+
+  // Gets icon image bounds of the item at |index|, relative to
+  // AppListFolderView.
+  gfx::Rect GetItemIconBoundsAt(int index);
+
+

[xiyuan, 2014/01/16 01:46:48]

nit: nuke one empty line

[jennyz, 2014/01/16 17:49:52]

Done.

+  // views::View overrides:
   virtual gfx::Size GetPreferredSize() OVERRIDE;
   virtual void Layout() OVERRIDE;
   virtual bool OnKeyPressed(const ui::KeyEvent& event) OVERRIDE;
 
+  // ui::ImplicitAnimationObserver overrides:
+  virtual void OnImplicitAnimationsCompleted() OVERRIDE;
+
  private:
   void CalculateIdealBounds();
 
   // Overridden from FolderHeaderViewDelegate:
   virtual void NavigateBack(AppListFolderItem* item,
                             const ui::Event& event_flags) OVERRIDE;
 
   AppsContainerView* container_view_;  // Not owned.
   FolderHeaderView* folder_header_view_;  // Owned by views hierarchy.
   AppsGridView* items_grid_view_;  // Owned by the views hierarchy.
 
   scoped_ptr<views::ViewModel> view_model_;
 
   AppListFolderItem* folder_item_;  // Not owned.
 
   scoped_ptr<PaginationModel> pagination_model_;
 
+  // Animated to show or hide the view.
+  bool animate_to_show_;
+
   DISALLOW_COPY_AND_ASSIGN(AppListFolderView);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_VIEWS_APP_LIST_FOLDER_VIEW_H_