native_menu_win.h revision 2a99a7e74a7f215066514fe81d2bfa6639d9eddd 
1// Copyright (c) 2012 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_NATIVE_MENU_WIN_H_
6#define UI_VIEWS_CONTROLS_MENU_NATIVE_MENU_WIN_H_
7
8#include <vector>
9
10#include "base/basictypes.h"
11#include "base/compiler_specific.h"
12#include "base/memory/scoped_ptr.h"
13#include "base/memory/weak_ptr.h"
14#include "base/observer_list.h"
15#include "base/string16.h"
16#include "ui/views/controls/menu/menu_wrapper.h"
17#include "ui/views/views_export.h"
18
19namespace ui {
20class MenuModel;
21}
22
23namespace views {
24
25// A Windows implementation of MenuWrapper.
26// TODO(beng): rename to MenuWin once the old class is dead.
27class VIEWS_EXPORT NativeMenuWin : public MenuWrapper {
28 public:
29  // Construct a NativeMenuWin, with a model and delegate. If |system_menu_for|
30  // is non-NULL, the NativeMenuWin wraps the system menu for that window.
31  // The caller owns the model and the delegate.
32  NativeMenuWin(ui::MenuModel* model, HWND system_menu_for);
33  virtual ~NativeMenuWin();
34
35  // Overridden from MenuWrapper:
36  virtual void RunMenuAt(const gfx::Point& point, int alignment) OVERRIDE;
37  virtual void CancelMenu() OVERRIDE;
38  virtual void Rebuild(InsertionDelegate* delegate) OVERRIDE;
39  virtual void UpdateStates() OVERRIDE;
40  virtual HMENU GetNativeMenu() const OVERRIDE;
41  virtual MenuAction GetMenuAction() const OVERRIDE;
42  virtual void AddMenuListener(MenuListener* listener) OVERRIDE;
43  virtual void RemoveMenuListener(MenuListener* listener) OVERRIDE;
44  virtual void SetMinimumWidth(int width) OVERRIDE;
45
46 private:
47  // IMPORTANT: Note about indices.
48  //            Functions in this class deal in two index spaces:
49  //            1. menu_index - the index of an item within the actual Windows
50  //               native menu.
51  //            2. model_index - the index of the item within our model.
52  //            These two are most often but not always the same value! The
53  //            notable exception is when this object is used to wrap the
54  //            Windows System Menu. In this instance, the model indices start
55  //            at 0, but the insertion index into the existing menu is not.
56  //            It is important to take this into consideration when editing the
57  //            code in the functions in this class.
58
59  struct HighlightedMenuItemInfo;
60
61  // Returns true if the item at the specified index is a separator.
62  bool IsSeparatorItemAt(int menu_index) const;
63
64  // Add items. See note above about indices.
65  void AddMenuItemAt(int menu_index, int model_index);
66  void AddSeparatorItemAt(int menu_index, int model_index);
67
68  // Sets the state of the item at the specified index.
69  void SetMenuItemState(int menu_index,
70                        bool enabled,
71                        bool checked,
72                        bool is_default);
73
74  // Sets the label of the item at the specified index.
75  void SetMenuItemLabel(int menu_index,
76                        int model_index,
77                        const string16& label);
78
79  // Updates the local data structure with the correctly formatted version of
80  // |label| at the specified model_index, and adds string data to |mii| if
81  // the menu is not owner-draw. That's a mouthful. This function exists because
82  // of the peculiarities of the Windows menu API.
83  void UpdateMenuItemInfoForString(MENUITEMINFO* mii,
84                                   int model_index,
85                                   const string16& label);
86
87  // Returns the alignment flags to be passed to TrackPopupMenuEx, based on the
88  // supplied alignment and the UI text direction.
89  UINT GetAlignmentFlags(int alignment) const;
90
91  // Resets the native menu stored in |menu_| by destroying any old menu then
92  // creating a new empty one.
93  void ResetNativeMenu();
94
95  // Creates the host window that receives notifications from the menu.
96  void CreateHostWindow();
97
98  // Callback from task to notify menu it was selected.
99  void DelayedSelect();
100
101  // Given a menu that's currently popped-up, find the currently highlighted
102  // item. Returns true if a highlighted item was found.
103  static bool GetHighlightedMenuItemInfo(HMENU menu,
104                                         HighlightedMenuItemInfo* info);
105
106  // Hook to receive keyboard events while the menu is open.
107  static LRESULT CALLBACK MenuMessageHook(
108      int n_code, WPARAM w_param, LPARAM l_param);
109
110  // Our attached model and delegate.
111  ui::MenuModel* model_;
112
113  HMENU menu_;
114
115  // True if the contents of menu items in this menu are drawn by the menu host
116  // window, rather than Windows.
117  bool owner_draw_;
118
119  // An object that collects all of the data associated with an individual menu
120  // item.
121  struct ItemData;
122  std::vector<ItemData*> items_;
123
124  // The window that receives notifications from the menu.
125  class MenuHostWindow;
126  friend MenuHostWindow;
127  scoped_ptr<MenuHostWindow> host_window_;
128
129  // The HWND this menu is the system menu for, or NULL if the menu is not a
130  // system menu.
131  HWND system_menu_for_;
132
133  // The index of the first item in the model in the menu.
134  int first_item_index_;
135
136  // The action that took place during the call to RunMenuAt.
137  MenuAction menu_action_;
138
139  // A list of listeners to call when the menu opens.
140  ObserverList<MenuListener> listeners_;
141
142  // Keep track of whether the listeners have already been called at least
143  // once.
144  bool listeners_called_;
145
146  // See comment in MenuMessageHook for details on these.
147  NativeMenuWin* menu_to_select_;
148  int position_to_select_;
149  base::WeakPtrFactory<NativeMenuWin> menu_to_select_factory_;
150
151  // If we're a submenu, this is our parent.
152  NativeMenuWin* parent_;
153
154  // If non-null the destructor sets this to true. This is set to non-null while
155  // the menu is showing. It is used to detect if the menu was deleted while
156  // running.
157  bool* destroyed_flag_;
158
159  // Ugly: a static pointer to the instance of this class that currently
160  // has a menu open, because our hook function that receives keyboard
161  // events doesn't have a mechanism to get a user data pointer.
162  static NativeMenuWin* open_native_menu_win_;
163
164  DISALLOW_COPY_AND_ASSIGN(NativeMenuWin);
165};
166
167}  // namespace views
168
169#endif  // UI_VIEWS_CONTROLS_MENU_NATIVE_MENU_WIN_H_
170