dom/media/BackgroundVideoDecodingPermissionObserver.h

   1 /* vim:set ts=2 sw=2 sts=2 et cindent: */
   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 #if !defined(BackgroundVideoDecodingPermissionObserver_h_)
   7 #  define BackgroundVideoDecodingPermissionObserver_h_
   8
   9 #  include "nsIObserver.h"
  10 #  include "nsISupportsImpl.h"
  11
  12 class nsISupports;
  13 class nsPIDOMWindowOuter;
  14
  15 namespace mozilla {
  16
  17 namespace dom {
  18 class Document;
  19 class BrowsingContext;
  20 }  // namespace dom
  21
  22 class MediaDecoder;
  23
  24 class BackgroundVideoDecodingPermissionObserver final : public nsIObserver {
  25  public:
  26   NS_DECL_ISUPPORTS
  27
  28   explicit BackgroundVideoDecodingPermissionObserver(MediaDecoder* aDecoder);
  29
  30   NS_IMETHOD Observe(nsISupports* aSubject, const char* aTopic,
  31                      const char16_t* aData) override;
  32   void RegisterEvent();
  33   void UnregisterEvent();
  34
  35  private:
  36   ~BackgroundVideoDecodingPermissionObserver();
  37   void EnableEvent() const;
  38   void DisableEvent() const;
  39   dom::BrowsingContext* GetOwnerBC() const;
  40   dom::Document* GetOwnerDoc() const;
  41   bool IsValidEventSender(nsISupports* aSubject) const;
  42
  43   // The life cycle of observer would always be shorter than decoder, so we
  44   // use raw pointer here.
  45   MediaDecoder* mDecoder;
  46   bool mIsRegisteredForEvent;
  47 };
  48
  49 }  // namespace mozilla
  50
  51 #endif  // BackgroundVideoDecodingPermissionObserver_h_