ui/views/controls/menu/menu_2.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_VIEWS_CONTROLS_MENU_MENU_2_H_
   6 #define UI_VIEWS_CONTROLS_MENU_MENU_2_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "ui/gfx/native_widget_types.h"
  11 #include "ui/views/controls/menu/menu_wrapper.h"
  12 #include "ui/views/views_export.h"
  13
  14 namespace gfx {
  15 class Point;
  16 }
  17
  18 namespace ui {
  19 class MenuModel;
  20 }
  21
  22 namespace views {
  23
  24 // A menu. Populated from a model, and relies on a delegate to execute commands.
  25 //
  26 // WARNING: do NOT create and use Menu2 on the stack. Menu2 notifies the model
  27 // of selection AFTER a delay. This means that if use a Menu2 on the stack
  28 // ActivatedAt is never invoked.
  29 class VIEWS_EXPORT Menu2 {
  30  public:
  31   // How the menu is aligned relative to the point it is shown at.
  32   // The alignment is reversed by menu if text direction is right to left.
  33   enum Alignment {
  34     ALIGN_TOPLEFT,
  35     ALIGN_TOPRIGHT
  36   };
  37
  38   // Creates a new menu populated with the contents of |model|.
  39   // WARNING: this populates the menu on construction by invoking methods on
  40   // the model. As such, it is typically not safe to use this as the model
  41   // from the constructor. EG:
  42   //   MyClass : menu_(this) {}
  43   // is likely to have problems.
  44   explicit Menu2(ui::MenuModel* model);
  45   virtual ~Menu2();
  46
  47   // Runs the menu at the specified point. This method blocks until done.
  48   // RunContextMenuAt is the same, but the alignment is the default for a
  49   // context menu.
  50   void RunMenuAt(const gfx::Point& point, Alignment alignment);
  51   void RunContextMenuAt(const gfx::Point& point);
  52
  53   // Cancels the active menu.
  54   void CancelMenu();
  55
  56   // Called when the model supplying data to this menu has changed, and the menu
  57   // must be rebuilt.
  58   void Rebuild();
  59
  60   // Called when the states of the menu items in the menu should be refreshed
  61   // from the model.
  62   void UpdateStates();
  63
  64   // For submenus.
  65   HMENU GetNativeMenu() const;
  66
  67   // Get the result of the last call to RunMenuAt to determine whether an
  68   // item was selected, the user navigated to a next or previous menu, or
  69   // nothing.
  70   MenuWrapper::MenuAction GetMenuAction() const;
  71
  72   // Add a listener to receive a callback when the menu opens.
  73   void AddMenuListener(MenuListener* listener);
  74
  75   // Remove a menu listener.
  76   void RemoveMenuListener(MenuListener* listener);
  77
  78   // Accessors.
  79   ui::MenuModel* model() const { return model_; }
  80
  81   // Sets the minimum width of the menu.
  82   void SetMinimumWidth(int width);
  83
  84  private:
  85
  86   ui::MenuModel* model_;
  87
  88   // The object that actually implements the menu.
  89   scoped_ptr<MenuWrapper> wrapper_;
  90
  91   DISALLOW_COPY_AND_ASSIGN(Menu2);
  92 };
  93
  94 }  // namespace views
  95
  96 #endif  // UI_VIEWS_CONTROLS_MENU_MENU_2_H_