javascript - 主干 View : Inherit and extend events from parent

Question

Backbone 的文档指出:

The events property may also be defined as a function that returns an events hash, to make it easier to programmatically define your events, as well as inherit them from parent views.

如何继承父 View 事件并扩展它们？

父 View

var ParentView = Backbone.View.extend({
   events: {
      'click': 'onclick'
   }
});

subview

var ChildView = ParentView.extend({
   events: function(){
      ????
   }
});

Answer 1

一种方法是:

var ChildView = ParentView.extend({
   events: function(){
      return _.extend({},ParentView.prototype.events,{
          'click' : 'onclickChild'
      });
   }
});

另一个是:

var ParentView = Backbone.View.extend({
   originalEvents: {
      'click': 'onclick'
   },
   //Override this event hash in
   //a child view
   additionalEvents: {
   },
   events : function() {
      return _.extend({},this.originalEvents,this.additionalEvents);
   }
});

var ChildView = ParentView.extend({
   additionalEvents: {
      'click' : ' onclickChild'
   }
});

检查事件是函数还是对象

var ChildView = ParentView.extend({
   events: function(){
      var parentEvents = ParentView.prototype.events;
      if(_.isFunction(parentEvents)){
          parentEvents = parentEvents();
      }
      return _.extend({},parentEvents,{
          'click' : 'onclickChild'
      });
   }
});