Allow some Android media player implementation to be overridden by embedders.

content/browser/android/media_player_manager_impl.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_ANDROID_MEDIA_PLAYER_MANAGER_IMPL_H_
 #define CONTENT_BROWSER_ANDROID_MEDIA_PLAYER_MANAGER_IMPL_H_
 
 #include <map>
 
 #include "base/callback.h"
@@ skipping 20 matching lines @@
 class MediaPlayerManagerImpl
     : public RenderViewHostObserver,
       public media::MediaPlayerManager {
  public:
   virtual ~MediaPlayerManagerImpl();
 
   // RenderViewHostObserver overrides.
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 
   // Fullscreen video playback controls.
-  void FullscreenPlayerPlay();
-  void FullscreenPlayerPause();
-  void FullscreenPlayerSeek(int msec);
-  void ExitFullscreen(bool release_media_player);
-  void SetVideoSurface(jobject surface);
+  virtual void FullscreenPlayerPlay();

[qinmin, 2013/05/25 04:41:44]

if you really need to override so many functions, why not inherit from
MediaPlayerManager?

[whywhat, 2013/05/28 15:16:40]

I only need to override a few of them but it feels wrong to selectively declare
some of these methods virtual. If I inherit from MediaPlayerManager I'll have to
duplicate lots of stuff that MediaPlayerManagerIml already does.

+  virtual void FullscreenPlayerPause();
+  virtual void FullscreenPlayerSeek(int msec);
+  virtual void ExitFullscreen(bool release_media_player);
+  virtual void SetVideoSurface(jobject surface);
 
   // media::MediaPlayerManager overrides.
   virtual void OnTimeUpdate(
       int player_id, base::TimeDelta current_time) OVERRIDE;
   virtual void OnMediaMetadataChanged(
       int player_id,
       base::TimeDelta duration,
       int width,
       int height,
       bool success) OVERRIDE;
@@ skipping 24 matching lines @@
 #endif
 
  protected:
   friend MediaPlayerManager* MediaPlayerManager::Create(
       content::RenderViewHost*);
 
   // The instance of this class is supposed to be created by either Create()
   // method of MediaPlayerManager or the derived classes constructors.
   explicit MediaPlayerManagerImpl(RenderViewHost* render_view_host);
 
- private:
   // Message handlers.
-  void OnEnterFullscreen(int player_id);
-  void OnExitFullscreen(int player_id);
-  void OnInitialize(int player_id, const GURL& url,
+  virtual void OnEnterFullscreen(int player_id);

[qinmin, 2013/05/29 04:42:19]

all these message handlers are now public just for 1 particular use case..
I think you can keep these methods private and declare a
RemoteMediaPlayerManagerImpl class, which inherits from MediaPlayerManagerImpl.
In the RemoteMediaPlayerManagerImpl, you override these method and declare them
public

[whywhat, 2013/05/29 15:49:18]

The handlers are protected, not public. Not only I need to override some of them
but also to call the base class version from the subclass to reuse the existing
implementation.

On 2013/05/29 04:42:19, qinmin wrote:

+  virtual void OnExitFullscreen(int player_id);
+  virtual void OnInitialize(int player_id, const GURL& url,
                     bool is_media_source,

[qinmin, 2013/05/29 04:42:19]

fix indentation

[whywhat, 2013/05/29 15:49:18]

Done.

                     const GURL& first_party_for_cookies);
-  void OnStart(int player_id);
-  void OnSeek(int player_id, base::TimeDelta time);
-  void OnPause(int player_id);
-  void OnReleaseResources(int player_id);
-  void OnDestroyPlayer(int player_id);
-  void OnDemuxerReady(
+  virtual void OnStart(int player_id);
+  virtual void OnSeek(int player_id, base::TimeDelta time);
+  virtual void OnPause(int player_id);
+  virtual void OnReleaseResources(int player_id);
+  virtual void OnDestroyPlayer(int player_id);
+  virtual void OnDemuxerReady(
       int player_id,
       const media::MediaPlayerHostMsg_DemuxerReady_Params& params);
-  void OnReadFromDemuxerAck(
+  virtual void OnReadFromDemuxerAck(
       int player_id,
       const media::MediaPlayerHostMsg_ReadFromDemuxerAck_Params& params);
 
 #if defined(GOOGLE_TV)
-  void OnNotifyExternalSurface(
+  virtual void OnNotifyExternalSurface(
       int player_id, bool is_request, const gfx::RectF& rect);
 #endif
 
+  // Adds a given player to the list.
+  void AddPlayer(media::MediaPlayerAndroid* player);
+
+  // Removes the player with the specified id.
+  void RemovePlayer(int player_id);
+
+ private:
   // An array of managed players.
   ScopedVector<media::MediaPlayerAndroid> players_;
 
   // The fullscreen video view object.
   ContentVideoView video_view_;
 
   // Player ID of the fullscreen media player.
   int fullscreen_player_id_;
 
   WebContents* web_contents_;
 
   // Object for retrieving resources media players.
   scoped_ptr<media::MediaResourceGetter> media_resource_getter_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaPlayerManagerImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_ANDROID_MEDIA_PLAYER_MANAGER_IMPL_H_