用JavaScript实现仿Windows关机效果

核心提示： 下面看一下网页加载时需要添加的方法，有关网页加载和初始化方法代码如下：//网页加载调用initialize和getBrowserInfo方法Event.observe(window, 'load', initialize, false);Event.observe(wind

下面看一下网页加载时需要添加的方法。有关网页加载和初始化方法代码如下：//网页加载调用initialize和getBrowserInfo方法
Event.observe(window, 'load', initialize, false);
Event.observe(window, 'load', getBrowserInfo, false);
//未加载时清空缓存
Event.observe(window, 'unload', Event.unloadCache, false);
//初始化方法
function initialize(){
//调用该方法为该页添加覆盖层和高亮显示层
addLightboxMarkup();
//为每个可高亮显示的元素创建lightbox对象
lbox = document.getElementsByClassName('lbOn');
for(i = 0; i < lbox.length; i++) {
valid = new lightbox(lbox[i]);
}
}
// 使用Dom方法创建覆盖层和高亮层
function addLightboxMarkup() {
bod = document.getElementsByTagName('body')[0];
overlay = document.createElement('div');
overlay.id = 'overlay';
lb = document.createElement('div');
lb.id = 'lightbox';
lb.className = 'loading';
lb.innerHTML = '<div id="lbLoadMessage">' +
'<p>Loading</p>' +
'</div>';
bod.appendChild(overlay);
bod.appendChild(lb);
}

封装lightbox类

初始化数据时，为每个可高亮显示的链接创建了lightbox对象。该类的代码具体实现如下：var lightbox = Class.create();　
lightbox.prototype = {
yPos : 0,
xPos : 0,
//构造方法,ctrl为创建该对象的元素
initialize: function(ctrl) {
//将该元素的链接赋值给this.content
this.content = ctrl.href;
//为该元素添加onclick事件activate方法
Event.observe(ctrl, 'click', this.activate.bindAsEventListener(this), false);
ctrl.onclick = function(){return false;};
},
//当单击链接时
activate: function(){
if (browser == 'Internet Explorer'){//判断为IE浏览器
this.getScroll();
this.prepareIE('100%', 'hidden');
this.setScroll(0,0);
this.hideSelects('hidden');//隐藏所有的<select>标记
}
//调用该类中的displayLightbox方法
this.displayLightbox("block");
},
prepareIE: function(height, overflow){
bod = document.getElementsByTagName('body')[0];
bod.style.height = height;
bod.style.overflow = overflow;
htm = document.getElementsByTagName('html')[0];
htm.style.height = height;
htm.style.overflow = overflow;
},
hideSelects: function(visibility){
selects = document.getElementsByTagName('select');
for(i = 0; i < selects.length; i++) {
selects[i].style.visibility = visibility;
}
},
getScroll: function(){
if (self.pageYOffset) {
this.yPos = self.pageYOffset;
} else if (document.documentElement && document.documentElement.scrollTop){
this.yPos = document.documentElement.scrollTop;
} else if (document.body) {
this.yPos = document.body.scrollTop;
}
},
setScroll: function(x, y){
window.scrollTo(x, y);
},
displayLightbox: function(display){
//将覆盖层显示
$('overlay').style.display = display;
//将高亮层显示
$('lightbox').style.display = display;
//如果不是隐藏状态,则调用该类中的loadInfo方法
if(display != 'none') this.loadInfo();
},
//该方法发送Ajax请求
loadInf function() {
//当请求完成后调用本类中processInfo方法
var myAjax = new Ajax.Request(
this.content,
{method: 'get', parameters: "", onComplete: this.processInfo.bindAsEvent Listener (this)}
);
},
// 将返回的文本信息显示到高亮层上
processInf function(response){
//获得返回的文本数据
var result = response.responseText;
//显示到高亮层
info = "<div id='lbContent'>" + result + "</div>";
//在info元素前插入一个元素
new Insertion.Before($('lbLoadMessage'), info)
//改变该元素的class name的值
$('lightbox').className = "done";
//调用本类中actions方法
this.actions();
var ctrl=$('lightbox');
//为高亮层添加事件处理方法reset
Event.observe(ctrl, 'click', this.reset.bindAsEventListener(this), false);
ctrl.onclick = function(){return false;};
},
//恢复初始状态
reset:function(){
//隐藏覆盖层
$('overlay').style.display="none";
//清空返回数据
$('lbContent').innerHTML="";
//隐藏高亮层
$('lightbox').style.display="none";
},
// Search through new links within the lightbox, and attach click event
actions: function(){
lbActions = document.getElementsByClassName('lbAction');
for(i = 0; i < lbActions.length; i++) {
Event.observe(lbActions[i], 'click',
this[lbActions[i].rel].bindAs EventListener(this), false);
lbActions[i].onclick = function(){return false;};
}
}
}