title: MediaController play button not updating when song is playing
body: <p>I am trying to use the mediacontroller to play audio. I am able to get the audio working but when the song starts playing the play button on my mediacontroller does not update. If press the play button on the mediacontroller it pauses the song and seeks the progressbar. Then if i press pause it plays the song again. i am calling </p>
  
  <pre><code>mp.start() 
  </code></pre>
  
  <p>does this not update the play button. How can I get the button to change to the pause button when I call start?</p>
  
  <pre><code>public class QuickMusicPlayer implements MediaController.MediaPlayerControl {
  
  private final MediaPlayer mMediaPlayer;
  private final MediaController mMediaController;
  private Activity mActivity;
  
  public QuickMusicPlayer(View anchorView, Activity activity) {
      mActivity = activity;
      mMediaPlayer = new MediaPlayer();
      mMediaController = new MediaController(activity);
      mMediaController.setMediaPlayer(this);
      mMediaController.setAnchorView(anchorView);
      mMediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
      mMediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
          @Override
          public void onPrepared(MediaPlayer mp) {
              mp.start();
          }
      });
  }
  
  public void setUrl(String url) {
      mMediaPlayer.reset();
      if (TextUtils.isEmpty(url)) {
          ViewUtil.showCroutonAlert(mActivity, R.string.cant_play_music);
      } else {
          try {
  
              mMediaPlayer.setDataSource(url);
              mMediaPlayer.prepareAsync();
              mMediaController.setEnabled(true);
              mMediaController.show(0);
          } catch (IOException e) {
              e.printStackTrace();
          }
      }
  }
  
  @Override
  public void start() {
      mMediaPlayer.start();
  }
  
  @Override
  public void pause() {
      mMediaPlayer.pause();
  }
  
  @Override
  public int getDuration() {
      return mMediaPlayer.getDuration();
  }
  
  @Override
  public int getCurrentPosition() {
      return mMediaPlayer.getCurrentPosition();
  }
  
  @Override
  public void seekTo(int pos) {
      mMediaPlayer.seekTo(pos);
  }
  
  @Override
  public boolean isPlaying() {
      return mMediaPlayer.isPlaying();
  }
  
  @Override
  public int getBufferPercentage() {
      return 0;
  }
  
  @Override
  public boolean canPause() {
      return true;
  }
  
  @Override
  public boolean canSeekBackward() {
      return true;
  }
  
  @Override
  public boolean canSeekForward() {
      return true;
  }
  
  @Override
  public int getAudioSessionId() {
      return 0;
  }
  </code></pre>
  
  <p>}</p>