layer[XY]$)/,
eventMethods = {
preventDefault: 'isDefaultPrevented', //是否调用过preventDefault方法
//取消执行其他的事件处理函数并取消事件冒泡.如果同一个事件绑定了多个事件处理函数, 在其中一个事件处理函数中调用此方法后将不会继续调用其他的事件处理函数.
stopImmediatePropagation: 'isImmediatePropagationStopped', //是否调用过stopImmediatePropagation方法，
stopPropagation: 'isPropagationStopped' //是否调用过stopPropagation方法
}
//创建事件代理
function createProxy(event) {
var key, proxy = {
originalEvent: event
} //保存原始event
for (key in event)
if (!ignoreProperties.test(key) && event[key] !== undefined) proxy[key] = event[key] //复制event属性至proxy
//将preventDefault，stopImmediatePropagatio,stopPropagation方法定义到proxy上
$.each(eventMethods, function(name, predicate) {
proxy[name] = function() {
this[predicate] = returnTrue
return event[name].apply(event, arguments)
}
proxy[predicate] = returnFalse
})
return proxy
}
// emulates the 'defaultPrevented' property for browsers that have none
//event.defaultPrevented返回一个布尔值,表明当前事件的默认动作是否被取消,也就是是否执行了 event.preventDefault()方法.
function fix(event) {
if (!('defaultPrevented' in event)) {
event.defaultPrevented = false //初始值false
var prevent = event.preventDefault // 引用默认preventDefault
event.preventDefault = function() { //重写preventDefault
this.defaultPrevented = true
prevent.call(this)
}
}
}
//事件委托
$.fn.delegate = function(selector, event, callback) {
return this.each(function(i, element) {
add(element, event, callback, selector, function(fn) {
return function(e) {
//如果事件对象是element里的元素,取与selector相匹配的
var evt, match = $(e.target).closest(selector, element).get(0)
if (match) {
//evt成了一个拥有preventDefault，stopImmediatePropagatio,stopPropagation方法，currentTarge,liveFiredn属性的对象,另也有e的默认属性
evt = $.extend(createProxy(e), {
currentTarget: match,
liveFired: element
})
return fn.apply(match, [evt].concat([].slice.call(arguments, 1)))
}
}
})
})
}
//取消事件委托
$.fn.undelegate = function(selector, event, callback) {
return this.each(function() {
remove(this, event, callback, selector)
})
}
$.fn.live = function(event, callback) {
$(document.body).delegate(this.selector, event, callback)
return this
}
$.fn.die = function(event, callback) {
$(document.body).undelegate(this.selector, event, callback)
return this
}
//on也有live和事件委托的效果，所以可以只用on来绑定事件
$.fn.on = function(event, selector, callback) {
return !selector
关键词：zepto是啥