v4/java/android/support/v4/media/session/MediaControllerCompat.java - fp2-dev/platform/frameworks/support - Gitiles

 /*
  * Copyright (C) 2014 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package android.support.v4.media.session;

 import android.content.Context;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.RemoteException;
 import android.os.ResultReceiver;
 import android.support.v4.media.MediaMetadataCompat;
 import android.support.v4.media.RatingCompat;
 import android.support.v4.media.VolumeProviderCompat;
 import android.text.TextUtils;
 import android.view.KeyEvent;

 /**
  * Allows an app to interact with an ongoing media session. Media buttons and
  * other commands can be sent to the session. A callback may be registered to
  * receive updates from the session, such as metadata and play state changes.
  * <p>
  * A MediaController can be created if you have a {@link MediaSessionCompat.Token}
  * from the session owner.
  * <p>
  * MediaController objects are thread-safe.
  * <p>
  * This is a helper for accessing features in {@link android.media.session.MediaSession}
  * introduced after API level 4 in a backwards compatible fashion.
  */
 public final class MediaControllerCompat {
     private final MediaControllerImpl mImpl;

     /**
      * Creates a media controller from a session.
      *
      * @param session The session to be controlled.
      */
     public MediaControllerCompat(Context context, MediaSessionCompat session) {
         if (session == null) {
             throw new IllegalArgumentException("session must not be null");
         }

         if (android.os.Build.VERSION.SDK_INT >= 21) {
             mImpl = new MediaControllerImplApi21(context, session);
         } else {
             mImpl = new MediaControllerImplBase();
         }
     }

     /**
      * Creates a media controller from a session token which may have
      * been obtained from another process.
      *
      * @param sessionToken The token of the session to be controlled.
      * @throws RemoteException if the session is not accessible.
      */
     public MediaControllerCompat(Context context, MediaSessionCompat.Token sessionToken)
             throws RemoteException {
         if (sessionToken == null) {
             throw new IllegalArgumentException("sessionToken must not be null");
         }

         if (android.os.Build.VERSION.SDK_INT >= 21) {
             mImpl = new MediaControllerImplApi21(context, sessionToken);
         } else {
             mImpl = new MediaControllerImplBase();
         }
     }

     /**
      * Get a {@link TransportControls} instance for this session.
      *
      * @return A controls instance
      */
     public TransportControls getTransportControls() {
         return mImpl.getTransportControls();
     }

     /**
      * Send the specified media button event to the session. Only media keys can
      * be sent by this method, other keys will be ignored.
      *
      * @param keyEvent The media button event to dispatch.
      * @return true if the event was sent to the session, false otherwise.
      */
     public boolean dispatchMediaButtonEvent(KeyEvent keyEvent) {
         if (keyEvent == null) {
             throw new IllegalArgumentException("KeyEvent may not be null");
         }
         return mImpl.dispatchMediaButtonEvent(keyEvent);
     }

     /**
      * Get the current playback state for this session.
      *
      * @return The current PlaybackState or null
      */
     public PlaybackStateCompat getPlaybackState() {
         return mImpl.getPlaybackState();
     }

     /**
      * Get the current metadata for this session.
      *
      * @return The current MediaMetadata or null.
      */
     public MediaMetadataCompat getMetadata() {
         return mImpl.getMetadata();
     }

     /**
      * Get the rating type supported by the session. One of:
      * <ul>
      * <li>{@link RatingCompat#RATING_NONE}</li>
      * <li>{@link RatingCompat#RATING_HEART}</li>
      * <li>{@link RatingCompat#RATING_THUMB_UP_DOWN}</li>
      * <li>{@link RatingCompat#RATING_3_STARS}</li>
      * <li>{@link RatingCompat#RATING_4_STARS}</li>
      * <li>{@link RatingCompat#RATING_5_STARS}</li>
      * <li>{@link RatingCompat#RATING_PERCENTAGE}</li>
      * </ul>
      *
      * @return The supported rating type
      */
     public int getRatingType() {
         return mImpl.getRatingType();
     }

     /**
      * Get the current playback info for this session.
      *
      * @return The current playback info or null.
      */
     public PlaybackInfo getPlaybackInfo() {
         return mImpl.getPlaybackInfo();
     }

     /**
      * Adds a callback to receive updates from the Session. Updates will be
      * posted on the caller's thread.
      *
      * @param callback The callback object, must not be null.
      */
     public void registerCallback(Callback callback) {
         registerCallback(callback, null);
     }

     /**
      * Adds a callback to receive updates from the session. Updates will be
      * posted on the specified handler's thread.
      *
      * @param callback The callback object, must not be null.
      * @param handler The handler to post updates on. If null the callers thread
      *            will be used.
      */
     public void registerCallback(Callback callback, Handler handler) {
         if (callback == null) {
             throw new IllegalArgumentException("callback cannot be null");
         }
         if (handler == null) {
             handler = new Handler();
         }
         mImpl.registerCallback(callback, handler);
     }

     /**
      * Stop receiving updates on the specified callback. If an update has
      * already been posted you may still receive it after calling this method.
      *
      * @param callback The callback to remove
      */
     public void unregisterCallback(Callback callback) {
         if (callback == null) {
             throw new IllegalArgumentException("callback cannot be null");
         }
         mImpl.unregisterCallback(callback);
     }

     /**
      * Sends a generic command to the session. It is up to the session creator
      * to decide what commands and parameters they will support. As such,
      * commands should only be sent to sessions that the controller owns.
      *
      * @param command The command to send
      * @param params Any parameters to include with the command
      * @param cb The callback to receive the result on
      */
     public void sendCommand(String command, Bundle params, ResultReceiver cb) {
         if (TextUtils.isEmpty(command)) {
             throw new IllegalArgumentException("command cannot be null or empty");
         }
         mImpl.sendCommand(command, params, cb);
     }

     /**
      * Gets the underlying framework {@link android.media.session.MediaController} object.
      * <p>
      * This method is only supported on API 21+.
      * </p>
      *
      * @return The underlying {@link android.media.session.MediaController} object,
      * or null if none.
      */
     public Object getMediaController() {
         return mImpl.getMediaController();
     }

     /**
      * Callback for receiving updates on from the session. A Callback can be
      * registered using {@link #registerCallback}
      */
     public static abstract class Callback {
         final Object mCallbackObj;

         public Callback() {
             if (android.os.Build.VERSION.SDK_INT >= 21) {
                 mCallbackObj = MediaControllerCompatApi21.createCallback(new StubApi21());
             } else {
                 mCallbackObj = null;
             }
         }

         /**
          * Override to handle the session being destroyed. The session is no
          * longer valid after this call and calls to it will be ignored.
          */
         public void onSessionDestroyed() {
         }

         /**
          * Override to handle custom events sent by the session owner without a
          * specified interface. Controllers should only handle these for
          * sessions they own.
          *
          * @param event The event from the session.
          * @param extras Optional parameters for the event.
          */
         public void onSessionEvent(String event, Bundle extras) {
         }

         /**
          * Override to handle changes in playback state.
          *
          * @param state The new playback state of the session
          */
         public void onPlaybackStateChanged(PlaybackStateCompat state) {
         }

         /**
          * Override to handle changes to the current metadata.
          *
          * @param metadata The current metadata for the session or null if none.
          * @see MediaMetadata
          */
         public void onMetadataChanged(MediaMetadataCompat metadata) {
         }

         private class StubApi21 implements MediaControllerCompatApi21.Callback {
             @Override
             public void onSessionDestroyed() {
                 Callback.this.onSessionDestroyed();
             }

             @Override
             public void onSessionEvent(String event, Bundle extras) {
                 Callback.this.onSessionEvent(event, extras);
             }

             @Override
             public void onPlaybackStateChanged(Object stateObj) {
                 Callback.this.onPlaybackStateChanged(
                         PlaybackStateCompat.fromPlaybackState(stateObj));
             }

             @Override
             public void onMetadataChanged(Object metadataObj) {
                 Callback.this.onMetadataChanged(
                         MediaMetadataCompat.fromMediaMetadata(metadataObj));
             }
         }
     }

     /**
      * Interface for controlling media playback on a session. This allows an app
      * to send media transport commands to the session.
      */
     public static abstract class TransportControls {
         TransportControls() {
         }

         /**
          * Request that the player start its playback at its current position.
          */
         public abstract void play();

         /**
          * Request that the player pause its playback and stay at its current
          * position.
          */
         public abstract void pause();

         /**
          * Request that the player stop its playback; it may clear its state in
          * whatever way is appropriate.
          */
         public abstract void stop();

         /**
          * Move to a new location in the media stream.
          *
          * @param pos Position to move to, in milliseconds.
          */
         public abstract void seekTo(long pos);

         /**
          * Start fast forwarding. If playback is already fast forwarding this
          * may increase the rate.
          */
         public abstract void fastForward();

         /**
          * Skip to the next item.
          */
         public abstract void skipToNext();

         /**
          * Start rewinding. If playback is already rewinding this may increase
          * the rate.
          */
         public abstract void rewind();

         /**
          * Skip to the previous item.
          */
         public abstract void skipToPrevious();

         /**
          * Rate the current content. This will cause the rating to be set for
          * the current user. The Rating type must match the type returned by
          * {@link #getRatingType()}.
          *
          * @param rating The rating to set for the current content
          */
         public abstract void setRating(RatingCompat rating);
     }

     /**
      * Holds information about the way volume is handled for this session.
      */
     public static final class PlaybackInfo {
         /**
          * The session uses local playback.
          */
         public static final int PLAYBACK_TYPE_LOCAL = 1;
         /**
          * The session uses remote playback.
          */
         public static final int PLAYBACK_TYPE_REMOTE = 2;

         private final int mPlaybackType;
         // TODO update audio stream with AudioAttributes support version
         private final int mAudioStream;
         private final int mVolumeControl;
         private final int mMaxVolume;
         private final int mCurrentVolume;

         PlaybackInfo(int type, int stream, int control, int max, int current) {
             mPlaybackType = type;
             mAudioStream = stream;
             mVolumeControl = control;
             mMaxVolume = max;
             mCurrentVolume = current;
         }

         /**
          * Get the type of volume handling, either local or remote. One of:
          * <ul>
          * <li>{@link PlaybackInfo#PLAYBACK_TYPE_LOCAL}</li>
          * <li>{@link PlaybackInfo#PLAYBACK_TYPE_REMOTE}</li>
          * </ul>
          *
          * @return The type of volume handling this session is using.
          */
         public int getPlaybackType() {
             return mPlaybackType;
         }

         /**
          * Get the stream this is currently controlling volume on. When the volume
          * type is {@link PlaybackInfo#PLAYBACK_TYPE_REMOTE} this value does not
          * have meaning and should be ignored.
          *
          * @return The stream this session is playing on.
          */
         public int getAudioStream() {
             return mAudioStream;
         }

         /**
          * Get the type of volume control that can be used. One of:
          * <ul>
          * <li>{@link VolumeProviderCompat#VOLUME_CONTROL_ABSOLUTE}</li>
          * <li>{@link VolumeProviderCompat#VOLUME_CONTROL_RELATIVE}</li>
          * <li>{@link VolumeProviderCompat#VOLUME_CONTROL_FIXED}</li>
          * </ul>
          *
          * @return The type of volume control that may be used with this
          *         session.
          */
         public int getVolumeControl() {
             return mVolumeControl;
         }

         /**
          * Get the maximum volume that may be set for this session.
          *
          * @return The maximum allowed volume where this session is playing.
          */
         public int getMaxVolume() {
             return mMaxVolume;
         }

         /**
          * Get the current volume for this session.
          *
          * @return The current volume where this session is playing.
          */
         public int getCurrentVolume() {
             return mCurrentVolume;
         }
     }

     interface MediaControllerImpl {
         void registerCallback(Callback callback, Handler handler);

         void unregisterCallback(Callback callback);
         boolean dispatchMediaButtonEvent(KeyEvent keyEvent);
         TransportControls getTransportControls();
         PlaybackStateCompat getPlaybackState();
         MediaMetadataCompat getMetadata();
         int getRatingType();
         PlaybackInfo getPlaybackInfo();
         void sendCommand(String command, Bundle params, ResultReceiver cb);
         Object getMediaController();
     }

     // TODO: compatibility implementation
     static class MediaControllerImplBase implements MediaControllerImpl {
         @Override
         public void registerCallback(Callback callback, Handler handler) {
         }

         @Override
         public void unregisterCallback(Callback callback) {
         }

         @Override
         public boolean dispatchMediaButtonEvent(KeyEvent event) {
             return false;
         }

         @Override
         public TransportControls getTransportControls() {
             return null;
         }

         @Override
         public PlaybackStateCompat getPlaybackState() {
             return null;
         }

         @Override
         public MediaMetadataCompat getMetadata() {
             return null;
         }

         @Override
         public int getRatingType() {
             return 0;
         }

         @Override
         public PlaybackInfo getPlaybackInfo() {
             return null;
         }

         @Override
         public void sendCommand(String command, Bundle params, ResultReceiver cb) {
         }

         @Override
         public Object getMediaController() {
             return null;
         }
     }

     static class MediaControllerImplApi21 implements MediaControllerImpl {
         private final Object mControllerObj;

         public MediaControllerImplApi21(Context context, MediaSessionCompat session) {
             mControllerObj = MediaControllerCompatApi21.fromToken(context,
                     session.getSessionToken().getToken());
         }

         public MediaControllerImplApi21(Context context, MediaSessionCompat.Token sessionToken)
                 throws RemoteException {
             // TODO: refactor framework implementation
             mControllerObj = MediaControllerCompatApi21.fromToken(context,
                     sessionToken.getToken());
             if (mControllerObj == null) throw new RemoteException();
         }

         @Override
         public void registerCallback(Callback callback, Handler handler) {
             MediaControllerCompatApi21.registerCallback(mControllerObj, callback.mCallbackObj, handler);
         }

         @Override
         public void unregisterCallback(Callback callback) {
             MediaControllerCompatApi21.unregisterCallback(mControllerObj, callback.mCallbackObj);
         }

         @Override
         public boolean dispatchMediaButtonEvent(KeyEvent event) {
             return MediaControllerCompatApi21.dispatchMediaButtonEvent(mControllerObj, event);
         }

         @Override
         public TransportControls getTransportControls() {
             Object controlsObj = MediaControllerCompatApi21.getTransportControls(mControllerObj);
             return controlsObj != null ? new TransportControlsApi21(controlsObj) : null;
         }

         @Override
         public PlaybackStateCompat getPlaybackState() {
             Object stateObj = MediaControllerCompatApi21.getPlaybackState(mControllerObj);
             return stateObj != null ? PlaybackStateCompat.fromPlaybackState(stateObj) : null;
         }

         @Override
         public MediaMetadataCompat getMetadata() {
             Object metadataObj = MediaControllerCompatApi21.getMetadata(mControllerObj);
             return metadataObj != null ? MediaMetadataCompat.fromMediaMetadata(metadataObj) : null;
         }

         @Override
         public int getRatingType() {
             return MediaControllerCompatApi21.getRatingType(mControllerObj);
         }

         @Override
         public PlaybackInfo getPlaybackInfo() {
             Object volumeInfoObj = MediaControllerCompatApi21.getPlaybackInfo(mControllerObj);
             return volumeInfoObj != null ? new PlaybackInfo(
                     MediaControllerCompatApi21.PlaybackInfo.getPlaybackType(volumeInfoObj),
                     MediaControllerCompatApi21.PlaybackInfo.getLegacyAudioStream(volumeInfoObj),
                     MediaControllerCompatApi21.PlaybackInfo.getVolumeControl(volumeInfoObj),
                     MediaControllerCompatApi21.PlaybackInfo.getMaxVolume(volumeInfoObj),
                     MediaControllerCompatApi21.PlaybackInfo.getCurrentVolume(volumeInfoObj)) : null;
         }

         @Override
         public void sendCommand(String command, Bundle params, ResultReceiver cb) {
             MediaControllerCompatApi21.sendCommand(mControllerObj, command, params, cb);
         }

         @Override
         public Object getMediaController() {
             return mControllerObj;
         }
     }

     static class TransportControlsApi21 extends TransportControls {
         private final Object mControlsObj;

         public TransportControlsApi21(Object controlsObj) {
             mControlsObj = controlsObj;
         }

         @Override
         public void play() {
             MediaControllerCompatApi21.TransportControls.play(mControlsObj);
         }

         @Override
         public void pause() {
             MediaControllerCompatApi21.TransportControls.pause(mControlsObj);
         }

         @Override
         public void stop() {
             MediaControllerCompatApi21.TransportControls.stop(mControlsObj);
         }

         @Override
         public void seekTo(long pos) {
             MediaControllerCompatApi21.TransportControls.seekTo(mControlsObj, pos);
         }

         @Override
         public void fastForward() {
             MediaControllerCompatApi21.TransportControls.fastForward(mControlsObj);
         }

         @Override
         public void rewind() {
             MediaControllerCompatApi21.TransportControls.rewind(mControlsObj);
         }

         @Override
         public void skipToNext() {
             MediaControllerCompatApi21.TransportControls.skipToNext(mControlsObj);
         }

         @Override
         public void skipToPrevious() {
             MediaControllerCompatApi21.TransportControls.skipToPrevious(mControlsObj);
         }

         @Override
         public void setRating(RatingCompat rating) {
             MediaControllerCompatApi21.TransportControls.setRating(mControlsObj,
                     rating != null ? rating.getRating() : null);
         }
     }
 }
	/*
	* Copyright (C) 2014 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package android.support.v4.media.session;

	import android.content.Context;
	import android.os.Bundle;
	import android.os.Handler;
	import android.os.RemoteException;
	import android.os.ResultReceiver;
	import android.support.v4.media.MediaMetadataCompat;
	import android.support.v4.media.RatingCompat;
	import android.support.v4.media.VolumeProviderCompat;
	import android.text.TextUtils;
	import android.view.KeyEvent;

	/**
	* Allows an app to interact with an ongoing media session. Media buttons and
	* other commands can be sent to the session. A callback may be registered to
	* receive updates from the session, such as metadata and play state changes.
	* <p>
	* A MediaController can be created if you have a {@link MediaSessionCompat.Token}
	* from the session owner.
	* <p>
	* MediaController objects are thread-safe.
	* <p>
	* This is a helper for accessing features in {@link android.media.session.MediaSession}
	* introduced after API level 4 in a backwards compatible fashion.
	*/
	public final class MediaControllerCompat {
	private final MediaControllerImpl mImpl;

	/**
	* Creates a media controller from a session.
	*
	* @param session The session to be controlled.
	*/
	public MediaControllerCompat(Context context, MediaSessionCompat session) {
	if (session == null) {
	throw new IllegalArgumentException("session must not be null");
	}

	if (android.os.Build.VERSION.SDK_INT >= 21) {
	mImpl = new MediaControllerImplApi21(context, session);
	} else {
	mImpl = new MediaControllerImplBase();
	}
	}

	/**
	* Creates a media controller from a session token which may have
	* been obtained from another process.
	*
	* @param sessionToken The token of the session to be controlled.
	* @throws RemoteException if the session is not accessible.
	*/
	public MediaControllerCompat(Context context, MediaSessionCompat.Token sessionToken)
	throws RemoteException {
	if (sessionToken == null) {
	throw new IllegalArgumentException("sessionToken must not be null");
	}

	if (android.os.Build.VERSION.SDK_INT >= 21) {
	mImpl = new MediaControllerImplApi21(context, sessionToken);
	} else {
	mImpl = new MediaControllerImplBase();
	}
	}

	/**
	* Get a {@link TransportControls} instance for this session.
	*
	* @return A controls instance
	*/
	public TransportControls getTransportControls() {
	return mImpl.getTransportControls();
	}

	/**
	* Send the specified media button event to the session. Only media keys can
	* be sent by this method, other keys will be ignored.
	*
	* @param keyEvent The media button event to dispatch.
	* @return true if the event was sent to the session, false otherwise.
	*/
	public boolean dispatchMediaButtonEvent(KeyEvent keyEvent) {
	if (keyEvent == null) {
	throw new IllegalArgumentException("KeyEvent may not be null");
	}
	return mImpl.dispatchMediaButtonEvent(keyEvent);
	}

	/**
	* Get the current playback state for this session.
	*
	* @return The current PlaybackState or null
	*/
	public PlaybackStateCompat getPlaybackState() {
	return mImpl.getPlaybackState();
	}

	/**
	* Get the current metadata for this session.
	*
	* @return The current MediaMetadata or null.
	*/
	public MediaMetadataCompat getMetadata() {
	return mImpl.getMetadata();
	}

	/**
	* Get the rating type supported by the session. One of:
	* <ul>
	* <li>{@link RatingCompat#RATING_NONE}</li>
	* <li>{@link RatingCompat#RATING_HEART}</li>
	* <li>{@link RatingCompat#RATING_THUMB_UP_DOWN}</li>
	* <li>{@link RatingCompat#RATING_3_STARS}</li>
	* <li>{@link RatingCompat#RATING_4_STARS}</li>
	* <li>{@link RatingCompat#RATING_5_STARS}</li>
	* <li>{@link RatingCompat#RATING_PERCENTAGE}</li>
	* </ul>
	*
	* @return The supported rating type
	*/
	public int getRatingType() {
	return mImpl.getRatingType();
	}

	/**
	* Get the current playback info for this session.
	*
	* @return The current playback info or null.
	*/
	public PlaybackInfo getPlaybackInfo() {
	return mImpl.getPlaybackInfo();
	}

	/**
	* Adds a callback to receive updates from the Session. Updates will be
	* posted on the caller's thread.
	*
	* @param callback The callback object, must not be null.
	*/
	public void registerCallback(Callback callback) {
	registerCallback(callback, null);
	}

	/**
	* Adds a callback to receive updates from the session. Updates will be
	* posted on the specified handler's thread.
	*
	* @param callback The callback object, must not be null.
	* @param handler The handler to post updates on. If null the callers thread
	* will be used.
	*/
	public void registerCallback(Callback callback, Handler handler) {
	if (callback == null) {
	throw new IllegalArgumentException("callback cannot be null");
	}
	if (handler == null) {
	handler = new Handler();
	}
	mImpl.registerCallback(callback, handler);
	}

	/**
	* Stop receiving updates on the specified callback. If an update has
	* already been posted you may still receive it after calling this method.
	*
	* @param callback The callback to remove
	*/
	public void unregisterCallback(Callback callback) {
	if (callback == null) {
	throw new IllegalArgumentException("callback cannot be null");
	}
	mImpl.unregisterCallback(callback);
	}

	/**
	* Sends a generic command to the session. It is up to the session creator
	* to decide what commands and parameters they will support. As such,
	* commands should only be sent to sessions that the controller owns.
	*
	* @param command The command to send
	* @param params Any parameters to include with the command
	* @param cb The callback to receive the result on
	*/
	public void sendCommand(String command, Bundle params, ResultReceiver cb) {
	if (TextUtils.isEmpty(command)) {
	throw new IllegalArgumentException("command cannot be null or empty");
	}
	mImpl.sendCommand(command, params, cb);
	}

	/**
	* Gets the underlying framework {@link android.media.session.MediaController} object.
	* <p>
	* This method is only supported on API 21+.
	* </p>
	*
	* @return The underlying {@link android.media.session.MediaController} object,
	* or null if none.
	*/
	public Object getMediaController() {
	return mImpl.getMediaController();
	}

	/**
	* Callback for receiving updates on from the session. A Callback can be
	* registered using {@link #registerCallback}
	*/
	public static abstract class Callback {
	final Object mCallbackObj;

	public Callback() {
	if (android.os.Build.VERSION.SDK_INT >= 21) {
	mCallbackObj = MediaControllerCompatApi21.createCallback(new StubApi21());
	} else {
	mCallbackObj = null;
	}
	}

	/**
	* Override to handle the session being destroyed. The session is no
	* longer valid after this call and calls to it will be ignored.
	*/
	public void onSessionDestroyed() {
	}

	/**
	* Override to handle custom events sent by the session owner without a
	* specified interface. Controllers should only handle these for
	* sessions they own.
	*
	* @param event The event from the session.
	* @param extras Optional parameters for the event.
	*/
	public void onSessionEvent(String event, Bundle extras) {
	}

	/**
	* Override to handle changes in playback state.
	*
	* @param state The new playback state of the session
	*/
	public void onPlaybackStateChanged(PlaybackStateCompat state) {
	}

	/**
	* Override to handle changes to the current metadata.
	*
	* @param metadata The current metadata for the session or null if none.
	* @see MediaMetadata
	*/
	public void onMetadataChanged(MediaMetadataCompat metadata) {
	}

	private class StubApi21 implements MediaControllerCompatApi21.Callback {
	@Override
	public void onSessionDestroyed() {
	Callback.this.onSessionDestroyed();
	}

	@Override
	public void onSessionEvent(String event, Bundle extras) {
	Callback.this.onSessionEvent(event, extras);
	}

	@Override
	public void onPlaybackStateChanged(Object stateObj) {
	Callback.this.onPlaybackStateChanged(
	PlaybackStateCompat.fromPlaybackState(stateObj));
	}

	@Override
	public void onMetadataChanged(Object metadataObj) {
	Callback.this.onMetadataChanged(
	MediaMetadataCompat.fromMediaMetadata(metadataObj));
	}
	}
	}

	/**
	* Interface for controlling media playback on a session. This allows an app
	* to send media transport commands to the session.
	*/
	public static abstract class TransportControls {
	TransportControls() {
	}

	/**
	* Request that the player start its playback at its current position.
	*/
	public abstract void play();

	/**
	* Request that the player pause its playback and stay at its current
	* position.
	*/
	public abstract void pause();

	/**
	* Request that the player stop its playback; it may clear its state in
	* whatever way is appropriate.
	*/
	public abstract void stop();

	/**
	* Move to a new location in the media stream.
	*
	* @param pos Position to move to, in milliseconds.
	*/
	public abstract void seekTo(long pos);

	/**
	* Start fast forwarding. If playback is already fast forwarding this
	* may increase the rate.
	*/
	public abstract void fastForward();

	/**
	* Skip to the next item.
	*/
	public abstract void skipToNext();

	/**
	* Start rewinding. If playback is already rewinding this may increase
	* the rate.
	*/
	public abstract void rewind();

	/**
	* Skip to the previous item.
	*/
	public abstract void skipToPrevious();

	/**
	* Rate the current content. This will cause the rating to be set for
	* the current user. The Rating type must match the type returned by
	* {@link #getRatingType()}.
	*
	* @param rating The rating to set for the current content
	*/
	public abstract void setRating(RatingCompat rating);
	}

	/**
	* Holds information about the way volume is handled for this session.
	*/
	public static final class PlaybackInfo {
	/**
	* The session uses local playback.
	*/
	public static final int PLAYBACK_TYPE_LOCAL = 1;
	/**
	* The session uses remote playback.
	*/
	public static final int PLAYBACK_TYPE_REMOTE = 2;

	private final int mPlaybackType;
	// TODO update audio stream with AudioAttributes support version
	private final int mAudioStream;
	private final int mVolumeControl;
	private final int mMaxVolume;
	private final int mCurrentVolume;

	PlaybackInfo(int type, int stream, int control, int max, int current) {
	mPlaybackType = type;
	mAudioStream = stream;
	mVolumeControl = control;
	mMaxVolume = max;
	mCurrentVolume = current;
	}

	/**
	* Get the type of volume handling, either local or remote. One of:
	* <ul>
	* <li>{@link PlaybackInfo#PLAYBACK_TYPE_LOCAL}</li>
	* <li>{@link PlaybackInfo#PLAYBACK_TYPE_REMOTE}</li>
	* </ul>
	*
	* @return The type of volume handling this session is using.
	*/
	public int getPlaybackType() {
	return mPlaybackType;
	}

	/**
	* Get the stream this is currently controlling volume on. When the volume
	* type is {@link PlaybackInfo#PLAYBACK_TYPE_REMOTE} this value does not
	* have meaning and should be ignored.
	*
	* @return The stream this session is playing on.
	*/
	public int getAudioStream() {
	return mAudioStream;
	}

	/**
	* Get the type of volume control that can be used. One of:
	* <ul>
	* <li>{@link VolumeProviderCompat#VOLUME_CONTROL_ABSOLUTE}</li>
	* <li>{@link VolumeProviderCompat#VOLUME_CONTROL_RELATIVE}</li>
	* <li>{@link VolumeProviderCompat#VOLUME_CONTROL_FIXED}</li>
	* </ul>
	*
	* @return The type of volume control that may be used with this
	* session.
	*/
	public int getVolumeControl() {
	return mVolumeControl;
	}

	/**
	* Get the maximum volume that may be set for this session.
	*
	* @return The maximum allowed volume where this session is playing.
	*/
	public int getMaxVolume() {
	return mMaxVolume;
	}

	/**
	* Get the current volume for this session.
	*
	* @return The current volume where this session is playing.
	*/
	public int getCurrentVolume() {
	return mCurrentVolume;
	}
	}

	interface MediaControllerImpl {
	void registerCallback(Callback callback, Handler handler);

	void unregisterCallback(Callback callback);
	boolean dispatchMediaButtonEvent(KeyEvent keyEvent);
	TransportControls getTransportControls();
	PlaybackStateCompat getPlaybackState();
	MediaMetadataCompat getMetadata();
	int getRatingType();
	PlaybackInfo getPlaybackInfo();
	void sendCommand(String command, Bundle params, ResultReceiver cb);
	Object getMediaController();
	}

	// TODO: compatibility implementation
	static class MediaControllerImplBase implements MediaControllerImpl {
	@Override
	public void registerCallback(Callback callback, Handler handler) {
	}

	@Override
	public void unregisterCallback(Callback callback) {
	}

	@Override
	public boolean dispatchMediaButtonEvent(KeyEvent event) {
	return false;
	}

	@Override
	public TransportControls getTransportControls() {
	return null;
	}

	@Override
	public PlaybackStateCompat getPlaybackState() {
	return null;
	}

	@Override
	public MediaMetadataCompat getMetadata() {
	return null;
	}

	@Override
	public int getRatingType() {
	return 0;
	}

	@Override
	public PlaybackInfo getPlaybackInfo() {
	return null;
	}

	@Override
	public void sendCommand(String command, Bundle params, ResultReceiver cb) {
	}

	@Override
	public Object getMediaController() {
	return null;
	}
	}

	static class MediaControllerImplApi21 implements MediaControllerImpl {
	private final Object mControllerObj;

	public MediaControllerImplApi21(Context context, MediaSessionCompat session) {
	mControllerObj = MediaControllerCompatApi21.fromToken(context,
	session.getSessionToken().getToken());
	}

	public MediaControllerImplApi21(Context context, MediaSessionCompat.Token sessionToken)
	throws RemoteException {
	// TODO: refactor framework implementation
	mControllerObj = MediaControllerCompatApi21.fromToken(context,
	sessionToken.getToken());
	if (mControllerObj == null) throw new RemoteException();
	}

	@Override
	public void registerCallback(Callback callback, Handler handler) {
	MediaControllerCompatApi21.registerCallback(mControllerObj, callback.mCallbackObj, handler);
	}

	@Override
	public void unregisterCallback(Callback callback) {
	MediaControllerCompatApi21.unregisterCallback(mControllerObj, callback.mCallbackObj);
	}

	@Override
	public boolean dispatchMediaButtonEvent(KeyEvent event) {
	return MediaControllerCompatApi21.dispatchMediaButtonEvent(mControllerObj, event);
	}

	@Override
	public TransportControls getTransportControls() {
	Object controlsObj = MediaControllerCompatApi21.getTransportControls(mControllerObj);
	return controlsObj != null ? new TransportControlsApi21(controlsObj) : null;
	}

	@Override
	public PlaybackStateCompat getPlaybackState() {
	Object stateObj = MediaControllerCompatApi21.getPlaybackState(mControllerObj);
	return stateObj != null ? PlaybackStateCompat.fromPlaybackState(stateObj) : null;
	}

	@Override
	public MediaMetadataCompat getMetadata() {
	Object metadataObj = MediaControllerCompatApi21.getMetadata(mControllerObj);
	return metadataObj != null ? MediaMetadataCompat.fromMediaMetadata(metadataObj) : null;
	}

	@Override
	public int getRatingType() {
	return MediaControllerCompatApi21.getRatingType(mControllerObj);
	}

	@Override
	public PlaybackInfo getPlaybackInfo() {
	Object volumeInfoObj = MediaControllerCompatApi21.getPlaybackInfo(mControllerObj);
	return volumeInfoObj != null ? new PlaybackInfo(
	MediaControllerCompatApi21.PlaybackInfo.getPlaybackType(volumeInfoObj),
	MediaControllerCompatApi21.PlaybackInfo.getLegacyAudioStream(volumeInfoObj),
	MediaControllerCompatApi21.PlaybackInfo.getVolumeControl(volumeInfoObj),
	MediaControllerCompatApi21.PlaybackInfo.getMaxVolume(volumeInfoObj),
	MediaControllerCompatApi21.PlaybackInfo.getCurrentVolume(volumeInfoObj)) : null;
	}

	@Override
	public void sendCommand(String command, Bundle params, ResultReceiver cb) {
	MediaControllerCompatApi21.sendCommand(mControllerObj, command, params, cb);
	}

	@Override
	public Object getMediaController() {
	return mControllerObj;
	}
	}

	static class TransportControlsApi21 extends TransportControls {
	private final Object mControlsObj;

	public TransportControlsApi21(Object controlsObj) {
	mControlsObj = controlsObj;
	}

	@Override
	public void play() {
	MediaControllerCompatApi21.TransportControls.play(mControlsObj);
	}

	@Override
	public void pause() {
	MediaControllerCompatApi21.TransportControls.pause(mControlsObj);
	}

	@Override
	public void stop() {
	MediaControllerCompatApi21.TransportControls.stop(mControlsObj);
	}

	@Override
	public void seekTo(long pos) {
	MediaControllerCompatApi21.TransportControls.seekTo(mControlsObj, pos);
	}

	@Override
	public void fastForward() {
	MediaControllerCompatApi21.TransportControls.fastForward(mControlsObj);
	}

	@Override
	public void rewind() {
	MediaControllerCompatApi21.TransportControls.rewind(mControlsObj);
	}

	@Override
	public void skipToNext() {
	MediaControllerCompatApi21.TransportControls.skipToNext(mControlsObj);
	}

	@Override
	public void skipToPrevious() {
	MediaControllerCompatApi21.TransportControls.skipToPrevious(mControlsObj);
	}

	@Override
	public void setRating(RatingCompat rating) {
	MediaControllerCompatApi21.TransportControls.setRating(mControlsObj,
	rating != null ? rating.getRating() : null);
	}
	}
	}