app_list: Add transition for apps grid and search results.

ui/app_list/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_CONTENTS_VIEW_H_
+#define UI_APP_LIST_CONTENTS_VIEW_H_
+#pragma once
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/memory/scoped_ptr.h"
+#include "ui/views/view.h"
+
+namespace views {
+class BoundsAnimator;
+class ViewModel;
+}
+
+namespace app_list {
+
+class AppListModel;
+class AppListView;
+class PaginationModel;
+
+// A view to manage sub views under the search box (apps grid view + page
+// switcher and search results). The two sets of sub views are mutually
+// exclusive. ContentsView manages a show state to choose one set to show
+// and animates the transition between show states.
+class ContentsView : public views::View {
+ public:
+  ContentsView(AppListView* app_list_view,
+               PaginationModel* pagination_model);
+  virtual ~ContentsView();
+
+  void SetModel(AppListModel* model);
+
+  void ShowSearchResults(bool show);
+
+ private:
+  enum ShowState {
+    SHOW_APPS,
+    SHOW_SEARCH_RESULTS,
+  };
+
+  // Sets show state.
+  void SetShowState(ShowState show_state);
+
+  // Invoked when show state is changed.
+  void ShowStateChanged();
+
+  void CalculateIdealBounds();
+  void AnimateToIdealBounds();
+
+  // Overridden from views::View:
+  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual void Layout() OVERRIDE;
+  virtual bool OnKeyPressed(const views::KeyEvent& event) OVERRIDE;
+
+  ShowState show_state_;
+
+  scoped_ptr<views::ViewModel> view_model_;

[sky, 2012/06/08 02:57:25]

Since you create these in the constructor make them values, eg no scoped_ptr.

[tfarina, 2012/06/08 04:18:51]

By making them values, means that we will need to include the header files for
ViewModel and BoundsAnimator in this header file. I noticed you recommended
doing this in another review, but I fail to see why using scoped_ptr here is not
good. In which way it adds complexity? I found that scoped_ptr helps documenting
the ownership in a clear way.

[xiyuan, 2012/06/08 16:16:54]

Exactly. :) 

+  scoped_ptr<views::BoundsAnimator> bounds_animator_;
+
+  DISALLOW_COPY_AND_ASSIGN(ContentsView);
+};
+
+}  // namespace app_list
+
+#endif  // UI_APP_LIST_CONTENTS_VIEW_H_