[Toolbar] Base toolbar button class with background images for button states

chrome/browser/ui/views/toolbar/button_dropdown.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 CHROME_BROWSER_UI_VIEWS_TOOLBAR_BUTTON_DROPDOWN_H_
-#define CHROME_BROWSER_UI_VIEWS_TOOLBAR_BUTTON_DROPDOWN_H_
-
-#include "base/memory/weak_ptr.h"
-#include "ui/views/context_menu_controller.h"
-#include "ui/views/controls/button/image_button.h"
-
-namespace ui {
-class MenuModel;
-}
-
-namespace views {
-class MenuRunner;
-}
-
-////////////////////////////////////////////////////////////////////////////////
-//
-// ButtonDropDown
-//
-// A button class that when pressed (and held) or pressed (and drag down) will
-// display a menu
-//
-////////////////////////////////////////////////////////////////////////////////
-class ButtonDropDown : public views::ImageButton,
-                       public views::ContextMenuController {
- public:
-  // The button's class name.
-  static const char kViewClassName[];
-
-  // Takes ownership of the |model|.
-  ButtonDropDown(views::ButtonListener* listener, ui::MenuModel* model);
-  virtual ~ButtonDropDown();
-
-  // If menu is currently pending for long press - stop it.
-  void ClearPendingMenu();
-
-  // Indicates if menu is currently showing.
-  bool IsMenuShowing() const;
-
-  // Overridden from views::View
-  virtual bool OnMousePressed(const ui::MouseEvent& event) OVERRIDE;
-  virtual bool OnMouseDragged(const ui::MouseEvent& event) OVERRIDE;
-  virtual void OnMouseReleased(const ui::MouseEvent& event) OVERRIDE;
-  virtual const char* GetClassName() const OVERRIDE;
-  // Showing the drop down results in a MouseCaptureLost, we need to ignore it.
-  virtual void OnMouseCaptureLost() OVERRIDE {}
-  virtual void OnMouseExited(const ui::MouseEvent& event) OVERRIDE;
-  virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
-  virtual void GetAccessibleState(ui::AccessibleViewState* state) OVERRIDE;
-
-  // Overridden from views::ContextMenuController
-  virtual void ShowContextMenuForView(views::View* source,
-                                      const gfx::Point& point,
-                                      ui::MenuSourceType source_type) OVERRIDE;
-
- protected:
-  // Overridden from CustomButton. Returns true if the button should become
-  // pressed when a user holds the mouse down over the button. For this
-  // implementation, both left and right mouse buttons can trigger a change
-  // to the PUSHED state.
-  virtual bool ShouldEnterPushedState(const ui::Event& event) OVERRIDE;
-
-  // Returns if menu should be shown. Override this to change default behavior.
-  virtual bool ShouldShowMenu();
-
-  // Function to show the dropdown menu.
-  virtual void ShowDropDownMenu(ui::MenuSourceType source_type);
-
- private:
-  // The model that populates the attached menu.
-  scoped_ptr<ui::MenuModel> model_;
-
-  // Indicates if menu is currently showing.
-  bool menu_showing_;
-
-  // Y position of mouse when left mouse button is pressed
-  int y_position_on_lbuttondown_;
-
-  // Menu runner to display drop down menu.
-  scoped_ptr<views::MenuRunner> menu_runner_;
-
-  // A factory for tasks that show the dropdown context menu for the button.
-  base::WeakPtrFactory<ButtonDropDown> show_menu_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(ButtonDropDown);
-};
-
-#endif  // CHROME_BROWSER_UI_VIEWS_TOOLBAR_BUTTON_DROPDOWN_H_