jQuery自定义事件如何正确工作

Question

我无法找到任何有关jQuery中自定义事件实际实现的好资源。就像他们如何模拟事件冒泡等

Answer 1

这样：

// bubbling is internal 
trigger: function(event, data, elem /*, bubbling */) { 
// Event object or event type 
var type = event.type || event, 
    bubbling = arguments[3]; 

// Handle a global trigger 
if (!elem) { 
    // Don't bubble custom events when global (to avoid too much overhead) 
    event.stopPropagation(); 

    // Only trigger if we've ever bound an event for it 
    if (jQuery.event.global[ type ]) { 
     jQuery.each(jQuery.cache, function() { 
      if (this.events && this.events[type]) { 
       jQuery.event.trigger(event, data, this.handle.elem); 
      } 
     }); 
    } 
} 

// ... snip ... 
// Trigger the event, it is assumed that "handle" is a function 
var handle = elem.nodeType ? 
    jQuery.data(elem, "handle") : 
    (jQuery.data(elem, "__events__") || {}).handle; 

if (handle) { 
    handle.apply(elem, data); 
} 

var parent = elem.parentNode || elem.ownerDocument; 
// ... snip .... 
if (!event.isPropagationStopped() && parent) { 
    jQuery.event.trigger(event, data, parent, true); 

    } else if (!event.isDefaultPrevented()) { 
    // ... snip ... 
       jQuery.event.triggered = true; 
       target[ targetType ](); 
    } 
} 

这是怎么回事这里是如下：

当调用jQuery检查是否全局触发事件（$.trigger("event_name");）。

如果不正在全球触发，和传播尚未停止和所讨论的元件具有父元素（!event.isPropagationStopped() && parent）然后jQuery的调用手动触发事件的父元素上。

jQuery.event.trigger(event, data, parent, true); 

是有相当多的事情 - 看event.js在jQuery的源代码。

Answer 2

退房的tutorials

$(document).bind("eventType", ...); 
// This is equivalent to the plugin's $.subscribe("eventType", ...); 
$(document).trigger("eventType"); 
// equivalent to plugin's $.publish("eventType"); 

而且结帐这个SO question