layout/xul/nsRepeatService.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 //
   8 // nsRepeatService
   9 //
  10 #ifndef nsRepeatService_h__
  11 #define nsRepeatService_h__
  12
  13 #include "nsCOMPtr.h"
  14 #include "nsITimer.h"
  15 #include "nsString.h"
  16
  17 #define INITAL_REPEAT_DELAY 250
  18
  19 #ifdef XP_MACOSX
  20 #  define REPEAT_DELAY 25
  21 #else
  22 #  define REPEAT_DELAY 50
  23 #endif
  24
  25 class nsITimer;
  26
  27 namespace mozilla {
  28 namespace dom {
  29 class Document;
  30 }
  31 }  // namespace mozilla
  32
  33 class nsRepeatService final {
  34  public:
  35   typedef void (*Callback)(void* aData);
  36
  37   ~nsRepeatService();
  38
  39   // Start dispatching timer events to the callback. There is no memory
  40   // management of aData here; it is the caller's responsibility to call
  41   // Stop() before aData's memory is released.
  42   //
  43   // aCallbackName is the label of the callback, used to pass to
  44   // InitWithNamedCallbackFunc.
  45   //
  46   // aDocument is used to get the event target in Start(). We need an event
  47   // target to init mRepeatTimer.
  48   void Start(Callback aCallback, void* aCallbackData,
  49              mozilla::dom::Document* aDocument, const nsACString& aCallbackName,
  50              uint32_t aInitialDelay = INITAL_REPEAT_DELAY);
  51   // Stop dispatching timer events to the callback. If the repeat service
  52   // is not currently configured with the given callback and data, this
  53   // is just ignored.
  54   void Stop(Callback aCallback, void* aData);
  55
  56   static nsRepeatService* GetInstance();
  57   static void Shutdown();
  58
  59  protected:
  60   nsRepeatService();
  61
  62  private:
  63   // helper function to initialize callback function to mRepeatTimer
  64   void InitTimerCallback(uint32_t aInitialDelay);
  65
  66   Callback mCallback;
  67   void* mCallbackData;
  68   nsCString mCallbackName;
  69   nsCOMPtr<nsITimer> mRepeatTimer;
  70
  71 };  // class nsRepeatService
  72
  73 #endif