code: public void synchronize(CheerleaderPlayer player) {
          setTrack(player.getCurrentTrack());
          mLoader.setVisibility(INVISIBLE);
          mPlayPause.setVisibility(VISIBLE);
          setPlaying(player.isPlaying());
      }
docs: Synchronize the player view with the current player state.
  <p/>
  Basically, check if a track is loaded as well as the playing state.
  
  @param player player currently used.