Vertically centered app list page switcher

ui/app_list/views/page_switcher_vertical.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_PAGE_SWITCHER_H_
-#define UI_APP_LIST_VIEWS_PAGE_SWITCHER_H_
+#ifndef UI_APP_LIST_VIEWS_PAGE_SWITCHER_VERTICAL_H_
+#define UI_APP_LIST_VIEWS_PAGE_SWITCHER_VERTICAL_H_
 
 #include "base/macros.h"
 #include "ui/app_list/pagination_model_observer.h"
+#include "ui/app_list/views/page_switcher.h"
 #include "ui/views/controls/button/button.h"
-#include "ui/views/view.h"
 
 namespace app_list {
 
 class PaginationModel;
 
 // PageSwitcher represents its underlying PaginationModel with a button strip.
 // Each page in the PageinationModel has a button in the strip and when the
 // button is clicked, the corresponding page becomes selected.
-class PageSwitcher : public views::View,
-                     public views::ButtonListener,
-                     public PaginationModelObserver {
+class PageSwitcherVertical : public views::ButtonListener,
+                             public PaginationModelObserver,
+                             public PageSwitcher {

[xiyuan, 2017/06/13 18:29:55]

nit: Make PageSwitcher the first one

[weidongg, 2017/06/13 21:25:00]

Done.

  public:
-  explicit PageSwitcher(PaginationModel* model);
-  ~PageSwitcher() override;
+  explicit PageSwitcherVertical(PaginationModel* model);
+  ~PageSwitcherVertical() override;
 
-  // Returns the page index of the page switcher button under the point. If no
-  // page switcher button is under the point, -1 is return. |point| is in
-  // PageSwitcher's coordinates.
-  int GetPageForPoint(const gfx::Point& point) const;
-
-  // Shows hover for button under the point. |point| is in PageSwitcher's
-  // coordinates.
-  void UpdateUIForDragPoint(const gfx::Point& point);
+  // Overridden from PageSwitcher:
+  int GetPageForPoint(const gfx::Point& point) const override;
+  void UpdateUIForDragPoint(const gfx::Point& point) override;
 
   // Overridden from views::View:
   gfx::Size CalculatePreferredSize() const override;
   void Layout() override;
 
  private:
-  void CalculateButtonWidthAndSpacing(int contents_width);
+  void CalculateButtonHeightAndSpacing(int contents_height);
 
   // Overridden from views::ButtonListener:
   void ButtonPressed(views::Button* sender, const ui::Event& event) override;
 
   // Overridden from PaginationModelObserver:
   void TotalPagesChanged() override;
   void SelectedPageChanged(int old_selected, int new_selected) override;
   void TransitionStarted() override;
   void TransitionChanged() override;
 
   PaginationModel* model_;  // Owned by AppsGridView.
-  views::View* buttons_;  // Owned by views hierarchy.
+  views::View* buttons_;    // Owned by views hierarchy.
 
-  DISALLOW_COPY_AND_ASSIGN(PageSwitcher);
+  DISALLOW_COPY_AND_ASSIGN(PageSwitcherVertical);
 };
 
 }  // namespace app_list
 
-#endif  // UI_APP_LIST_VIEWS_PAGE_SWITCHER_H_
+#endif  // UI_APP_LIST_VIEWS_PAGE_SWITCHER_VERTICAL_H_