Allow app list tiles to show search results in the experimental app list.

ui/app_list/views/start_page_view.h

 // Copyright 2014 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_START_PAGE_VIEW_H_
 #define UI_APP_LIST_VIEWS_START_PAGE_VIEW_H_
 
 #include "base/basictypes.h"
-#include "ui/app_list/app_list_model_observer.h"
+#include "base/memory/weak_ptr.h"
+#include "ui/app_list/app_list_export.h"
+#include "ui/app_list/app_list_model.h"
 #include "ui/app_list/app_list_view_delegate_observer.h"
 #include "ui/app_list/views/search_box_view_delegate.h"
+#include "ui/base/models/list_model_observer.h"
 #include "ui/views/view.h"
 
 namespace app_list {
 
 class AppListMainView;
-class AppListModel;
 class AppListViewDelegate;
 class SearchResultListView;
 class TileItemView;
 
 // The start page for the experimental app list.
-class StartPageView : public views::View,
-                      public SearchBoxViewDelegate,
-                      public AppListViewDelegateObserver,
-                      public AppListModelObserver {
+class APP_LIST_EXPORT StartPageView : public views::View,
+                                      public ui::ListModelObserver,
+                                      public SearchBoxViewDelegate,
+                                      public AppListViewDelegateObserver {
  public:
   StartPageView(AppListMainView* app_list_main_view,
                 AppListViewDelegate* view_delegate);
   virtual ~StartPageView();
 
   void Reset();
   void ShowSearchResults();
 
   bool IsShowingSearchResults() const;
 
+  void UpdateForTesting();
+
   const std::vector<TileItemView*>& tile_views() const { return tile_views_; }
   SearchBoxView* dummy_search_box_view() { return search_box_view_; }
 
   // Overridden from views::View:
   virtual bool OnKeyPressed(const ui::KeyEvent& event) OVERRIDE;
   virtual void Layout() OVERRIDE;
 
  private:
   enum ShowState {
     SHOW_START_PAGE,
     SHOW_SEARCH_RESULTS,
   };
 
   void InitInstantContainer();
   void InitTilesContainer();
 
   void SetShowState(ShowState show_state);
   void SetModel(AppListModel* model);
 
+  // Updates UI with model.
+  void Update();
+
+  // Schedules an Update() call using |update_factory_|. Does nothing if there
+  // is a pending call.
+  void ScheduleUpdate();
+
   // Overridden from SearchBoxViewDelegate:
   virtual void QueryChanged(SearchBoxView* sender) OVERRIDE;
 
   // Overridden from AppListViewDelegateObserver:
   virtual void OnProfilesChanged() OVERRIDE;
 
-  // Overridden from AppListModelObserver:
-  virtual void OnAppListModelStatusChanged() OVERRIDE;
-  virtual void OnAppListItemAdded(AppListItem* item) OVERRIDE;
-  virtual void OnAppListItemDeleted() OVERRIDE;
-  virtual void OnAppListItemUpdated(AppListItem* item) OVERRIDE;
+  // Overridden from ui::ListModelObserver:
+  virtual void ListItemsAdded(size_t start, size_t count) OVERRIDE;
+  virtual void ListItemsRemoved(size_t start, size_t count) OVERRIDE;
+  virtual void ListItemMoved(size_t index, size_t target_index) OVERRIDE;
+  virtual void ListItemsChanged(size_t start, size_t count) OVERRIDE;
 
   // The parent view of ContentsView which is the parent of this view.
   AppListMainView* app_list_main_view_;
 
-  AppListModel* model_;  // Owned by AppListSyncableService.
+  AppListModel::SearchResults*
+      search_results_model_;  // Owned by AppListSyncableService.
 
   AppListViewDelegate* view_delegate_;  // Owned by AppListView.
 
   SearchBoxView* search_box_view_;      // Owned by views hierarchy.
   SearchResultListView* results_view_;  // Owned by views hierarchy.
   views::View* instant_container_;  // Owned by views hierarchy.
   views::View* tiles_container_;    // Owned by views hierarchy.
 
   std::vector<TileItemView*> tile_views_;
 
   ShowState show_state_;
 
+  // ScheduleUpdate() generates a single weak pointer; if one exists then an
+  // update is pending. Further calls to ScheduleUpdate() will have no effect.
+  // Once the Update() completes, the weak pointer is invalidated.
+  base::WeakPtrFactory<StartPageView> update_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(StartPageView);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_VIEWS_START_PAGE_VIEW_H_