js遮罩层，添加缓冲画面

function initialize() {

    addcloud(); //为页面添加遮罩

    document.onreadystatechange = subSomething; //监听加载状态改变

}

 

function addcloud() {

    var bodyWidth = document.documentElement.clientWidth;

    var bodyHeight = Math.max(document.documentElement.clientHeight, document.body.scrollHeight);

    var bgObj = document.createElement_x("div" );

    bgObj.setAttribute( 'id', 'bgDiv' );

    bgObj.style.position = "absolute";

    bgObj.style.top = "0";

    bgObj.style.background = "#000000";

    bgObj.style.filter = "progid:DXImageTransform.Microsoft.Alpha(style=3,opacity=25,finishOpacity=75" ;

    bgObj.style.opacity = "0.5";

    bgObj.style.left = "0";

    bgObj.style.width = bodyWidth + "px";

    bgObj.style.height = bodyHeight + "px";

    bgObj.style.zIndex = "10000"; //设置它的zindex属性，让这个div在z轴最大，用户点击页面任何东西都不会有反应|

    document.body.appendChild(bgObj); //添加遮罩

    var loadingObj = document.createElement_x("div");

    loadingObj.setAttribute( 'id', 'loadingDiv' );

    loadingObj.style.position = "absolute";

    loadingObj.style.top = bodyHeight / 2 - 32 + "px";

    loadingObj.style.left = bodyWidth / 2 + "px";

    loadingObj.style.background = "url(../img/loading.gif)" ;

    loadingObj.style.width = "32px";

    loadingObj.style.height = "32px";

    loadingObj.style.zIndex = "10000"; 

    document.body.appendChild(loadingObj); //添加loading动画-

}

 

function removecloud() {

    $( "#loadingDiv").remove();

    $( "#bgDiv").remove();

}

 

function subSomething() {

    if (document.readyState == "complete" ) //当页面加载完毕移除页面遮罩，移除loading动画-

    {

        removecloud();

    }

}