HeartView.js

function _setListeners() {
  this.heartSurface.on('click', this.clickListener.bind(this));
}

function HeartView() {
  View.apply(this, arguments);

  _createHeart.call(this); // create HeartSurface
  _setListeners.call(this);
}

HeartView.prototype = Object.create(View.prototype);
HeartView.prototype.constructor = HeartView;

HeartView.prototype.clickListener = function() {
  this._eventOutput.emit('sayThanks');
  this._eventOutput.emit('updateCounter');
};

HeartView.prototype.removeClickListener = function() {
  this.heartSurface.removeListener('click', this.clickListener.bind(this));
};