bindEvents_() {
    this.ws_.el.addEventListener(
      'ws:slide-change', this.onSlideChanged_.bind(this));
    this.next.addEventListener('click', this.onButtonClicked_.bind(this));
    this.prev.addEventListener('click', this.onButtonClicked_.bind(this));
    this.counter.addEventListener('click', this.onButtonClicked_.bind(this));
    document.body.addEventListener('click', this.onBodyClicked_.bind(this));
  }
Bind all events for the navigation.
@private