accessible/base/EventTree.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_a11y_EventTree_h_
   7 #define mozilla_a11y_EventTree_h_
   8
   9 #include "AccEvent.h"
  10 #include "LocalAccessible.h"
  11
  12 #include "mozilla/a11y/DocAccessible.h"
  13 #include "mozilla/RefPtr.h"
  14 #include "mozilla/UniquePtr.h"
  15
  16 namespace mozilla {
  17 namespace a11y {
  18
  19 class NotificationController;
  20
  21 /**
  22  * This class makes sure required tasks are done before and after tree
  23  * mutations. Currently this only includes group info invalidation. You must
  24  * have an object of this class on the stack when calling methods that mutate
  25  * the accessible tree.
  26  */
  27 class TreeMutation final {
  28  public:
  29   static const bool kNoEvents = true;
  30   static const bool kNoShutdown = true;
  31
  32   explicit TreeMutation(LocalAccessible* aParent, bool aNoEvents = false);
  33   ~TreeMutation();
  34
  35   void AfterInsertion(LocalAccessible* aChild);
  36   void BeforeRemoval(LocalAccessible* aChild, bool aNoShutdown = false);
  37   void Done();
  38
  39  private:
  40   NotificationController* Controller() const {
  41     return mParent->Document()->Controller();
  42   }
  43
  44   LocalAccessible* mParent;
  45   uint32_t mStartIdx;
  46   uint32_t mStateFlagsCopy;
  47
  48   /*
  49    * True if mutation events should be queued.
  50    */
  51   bool mQueueEvents;
  52
  53 #ifdef DEBUG
  54   bool mIsDone;
  55 #endif
  56 };
  57
  58 }  // namespace a11y
  59 }  // namespace mozilla
  60
  61 #endif  // mozilla_a11y_EventQueue_h_