_initNearBottomEvents: function() {
      this.iscroll.on('scroll', _.bind(this._triggerNearBottomEvents, this));
      this.iscroll.on('scrollEnd', _.bind(this._triggerNearBottomEvents, this));
      this.iscroll.on('afterkeyboard', _.bind(this._triggerNearBottomEvents, this));
    },