jQuery 实现观察者模式

https://github.com/mmikowski/jquery.event.gevent

$('body').append( "<div id='spa-chat-list-box' />" );

var $listbox = $('#spa-chat-list-box');

$listbox.css({
position   : "absolute",
'z-index'  : "3",
top        : "50",
left       : "50",
width      : "50",
height     : "50",
border     : "2px solid #ccc",
background : "#fff",
})

var onListchange = function ( event, update_map ){
$( this ).html(update_map.list_text);
alert("onListchange");
}

/* 订阅事件 */
$.gevent.subscribe(
$listbox,
'spa-listchange',
onListchange
);

/* 发布通知 */
$.gevent.publish(
'spa-listchange',
[{  list_text : 'the list is here'}]
);

/* 删除元素的话，订阅的事件也会删除 */
$listbox.remove();
$.gevent.publish('spa-listchange',[ { } ]);