Ext.util.Observable 中摘的一段代码，不知何解

Question

[code="java"] /**
* Relays selected events from the specified Observable as if the events were fired by this.
* @param {Object} o The Observable whose events this object is to relay.
* @param {Array} events Array of event names to relay.
*/
relayEvents : function(o, events){
var me = this;
function createHandler(ename){
return function(){
return me.fireEvent.apply(me, [ename].concat(Array.prototype.slice.call(arguments, 0)));
};
}
for(var i = 0, len = events.length; i < len; i++){
var ename = events[i];
me.events[ename] = me.events[ename] || true;
o.on(ename, createHandler(ename), me);
}
}[/code]

Answer 1

你是问用途么？

它的作用是将另一个Observable实例的指定事件，关联到自身上
例如实例a有e1事件，现在调用: b.relayEvents(a, ["e1"])
就会使a的e1事件触发时，b也会触发e1事件。