listener = function(event){
            if(this.onFocusChanged)
                this.onFocusChanged(event._widgetLoseFocus, event._widgetGetFocus);
        }
Create a EventListener object by json object
@function
@static
@param {object} argObj a json object
@returns {cc.EventListener}
todo: It should be the direct use new
@example
cc.EventListener.create({
      event: cc.EventListener.TOUCH_ONE_BY_ONE,
      swallowTouches: true,
      onTouchBegan: function (touch, event) {
          //do something
          return true;
      }
   });