isPlaying() {
    return this.getState().then(function (state) {
      return state === 'playing';
    });
  }
/**
   * Helper method to check if the player is in the play state
   *
   * @returns {Promise.<boolean>}
   */
Helper method to check if the player is in the play state
@returns {Promise.}
Helper method to check if the player is in the play state @returns { Promise . }
isPlaying() {
    return this.getState().then(function (state) {
      return state === 'playing';
    });
  }
isPlaying ( ) { return this . getState ( ) . then ( function ( state ) { return state === 'playing' ; } ) ; }
Helper method to check if the player is in the play state
 @returns {Promise.<boolean>}
Helper method to check if the player is in the play state @returns { Promise . <boolean > }