widget/NativeMenu.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef mozilla_widget_NativeMenu_h
   7 #define mozilla_widget_NativeMenu_h
   8
   9 #include "nsISupportsImpl.h"
  10 #include "Units.h"
  11
  12 class nsPresContext;
  13
  14 namespace mozilla {
  15 using Modifiers = uint16_t;
  16 class ErrorResult;
  17 }  // namespace mozilla
  18
  19 namespace mozilla::dom {
  20 class Element;
  21 }
  22
  23 namespace mozilla::widget {
  24
  25 class NativeMenu {
  26  public:
  27   NS_INLINE_DECL_REFCOUNTING(NativeMenu)
  28
  29   // Show this menu as a context menu at the specified position.
  30   // This call assumes that the popupshowing event for the root popup has
  31   // already been sent and "approved", i.e. preventDefault() was not called.
  32   virtual void ShowAsContextMenu(nsPresContext* aPc,
  33                                  const CSSIntPoint& aPosition) = 0;
  34
  35   // Close the menu and synchronously fire popuphiding / popuphidden events.
  36   // Returns false if the menu wasn't open.
  37   virtual bool Close() = 0;
  38
  39   // Activate aItemElement and close this menu.
  40   // aItemElement can be nested arbitrarily deeply within submenus inside this
  41   // menu. Only works while this menu (and any submenus on the path to the
  42   // item) is open, otherwise aRv reports an error.
  43   virtual void ActivateItem(dom::Element* aItemElement, Modifiers aModifiers,
  44                             int16_t aButton, ErrorResult& aRv) = 0;
  45
  46   // Open, or simulate the opening of, a submenu.
  47   // aMenuElement can be nested arbitrarily deeply within submenus inside this
  48   // menu. Only works while this menu (and any submenus on the path to the
  49   // submenu) is open.
  50   virtual void OpenSubmenu(dom::Element* aMenuElement) = 0;
  51
  52   // Closing, or simulate the closing of, a submenu.
  53   // aMenuElement can be nested arbitrarily deeply within submenus inside this
  54   // menu. Only works while this menu (and any submenus on the path to the
  55   // submenu) is open.
  56   virtual void CloseSubmenu(dom::Element* aMenuElement) = 0;
  57
  58   // Return this NativeMenu's DOM element.
  59   virtual RefPtr<dom::Element> Element() = 0;
  60
  61   class Observer {
  62    public:
  63     // Called when the menu opened, after popupshown.
  64     // No strong reference is held to the observer during the call.
  65     virtual void OnNativeMenuOpened() = 0;
  66
  67     // Called when the menu closed, after popuphidden.
  68     // No strong reference is held to the observer during the call.
  69     virtual void OnNativeMenuClosed() = 0;
  70
  71     // Called before the popupshowing event of a submenu fires.
  72     virtual void OnNativeSubMenuWillOpen(dom::Element* aPopupElement) = 0;
  73
  74     // Called after the popupshown event of a submenu fired.
  75     virtual void OnNativeSubMenuDidOpen(dom::Element* aPopupElement) = 0;
  76
  77     // Called after the popuphidden event of a submenu fired.
  78     virtual void OnNativeSubMenuClosed(dom::Element* aPopupElement) = 0;
  79
  80     // Called before the command event of an activated menu item fires.
  81     virtual void OnNativeMenuWillActivateItem(
  82         dom::Element* aMenuItemElement) = 0;
  83   };
  84
  85   // Add an observer that gets notified of menu opening and closing.
  86   // The menu does not keep a strong reference the observer. The observer must
  87   // remove itself before it is destroyed.
  88   virtual void AddObserver(Observer* aObserver) = 0;
  89
  90   // Remove an observer that was previously added with AddObserver.
  91   virtual void RemoveObserver(Observer* aObserver) = 0;
  92
  93  protected:
  94   virtual ~NativeMenu() = default;
  95 };
  96
  97 }  // namespace mozilla::widget
  98
  99 #endif  // mozilla_widget_NativeMenu_h