Draggable peeking/fullscreen launcher with transparent background.

ui/app_list/views/contents_view.h

 // 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.
 
 #ifndef UI_APP_LIST_VIEWS_CONTENTS_VIEW_H_
 #define UI_APP_LIST_VIEWS_CONTENTS_VIEW_H_
 
 #include <map>
 #include <memory>
 #include <utility>
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "ui/app_list/app_list_export.h"
 #include "ui/app_list/app_list_model.h"
 #include "ui/app_list/app_list_model_observer.h"
 #include "ui/app_list/pagination_model.h"
 #include "ui/app_list/pagination_model_observer.h"
 #include "ui/views/view.h"
 #include "ui/views/view_model.h"
 
 namespace gfx {
 class Rect;
 }
 
 namespace app_list {
 
 class AppsGridView;
 class AppListPage;
+class AppListView;
 class ApplicationDragAndDropHost;
 class AppListFolderItem;
 class AppListMainView;
 class AppsContainerView;
 class CustomLauncherPageView;
 class PaginationModel;
 class SearchBoxView;
 class SearchResultPageView;
 class StartPageView;
 
 // A view to manage launcher pages within the Launcher (eg. start page, apps
 // grid view, search results). There can be any number of launcher pages, only
 // one of which can be active at a given time. ContentsView provides the user
 // interface for switching between launcher pages, and animates the transition
 // between them.
 class APP_LIST_EXPORT ContentsView : public views::View,
                                      public PaginationModelObserver,
                                      public AppListModelObserver {
  public:
-  explicit ContentsView(AppListMainView* app_list_main_view);
+  explicit ContentsView(AppListMainView* app_list_main_view,

[xiyuan, 2017/05/30 22:18:50]

nit: remove "explicit". It is only needed for single arg ctor (or there are args
with default value).

[newcomer, 2017/06/01 01:42:54]

Done.

+                        AppListView* app_list_view);
   ~ContentsView() override;
 
   // Initialize the pages of the launcher. Should be called after
   // set_contents_switcher_view().
   void Init(AppListModel* model);
 
   // The app list gets closed and drag and drop operations need to be cancelled.
   void CancelDrag();
 
   // If |drag_and_drop| is not NULL it will be called upon drag and drop
@@ skipping 133 matching lines @@
   // Unowned pointer to the container of the search answer web view. This
   // container view is a sub-view of search_results_page_view_.
   View* search_answer_container_view_;
 
   // The child page views. Owned by the views hierarchy.
   std::vector<AppListPage*> app_list_pages_;
 
   // Parent view. Owned by the views hierarchy.
   AppListMainView* app_list_main_view_;
 
+  //  Owned by the views hierarchy.
+  AppListView* const app_list_view_;
+
   // Maps State onto |view_model_| indices.
   std::map<AppListModel::State, int> state_to_view_;
 
   // Maps |view_model_| indices onto State.
   std::map<int, AppListModel::State> view_to_state_;
 
   // The page that was showing before ShowSearchResults(true) was invoked.
   int page_before_search_;
 
   // Manages the pagination for the launcher pages.
   PaginationModel pagination_model_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentsView);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_VIEWS_CONTENTS_VIEW_H_