日期:2014-05-16  浏览次数:20452 次

js 如何实现div层的下滑,覆盖下面的那个层
 求一个问题,如何让蓝色的慢慢的滑下来,然后绿色的也慢慢的滑下去至到消失,蓝色滑至完全覆盖绿色然后停止,蓝色占据绿色原来的位置不显示。(动画效果)

------解决方案--------------------
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
#blue{
height:200px;
background-color:#00F;
}
#green{
height:200px;
background-color:#0F0;
}
</style>
<script type="text/javascript">
function init(){
var b=document.getElementById("blue");
var g=document.getElementById("green");
hides(b,g);
}
function getHeight(obj){
var style="";
if(document.defaultView&&document.defaultView.getComputedStyle){
style=document.defaultView.getComputedStyle(obj);
}else{
style=obj.currentStyle;
}
return style.height=="auto"?obj.offsetHeight:style.height;
}
function hides(b,g){
var bw=getHeight(b);
var gw=getHeight(g);
b.style.height=parseInt(bw)+2+"px";
g.style.height=parseInt(gw)-2+"px";
var p=window.setTimeout(function(){hides(b,g)},100);
if(parseInt(gw)==0){
window.clearTimeout(p);
}
}
window.onload=init;
</script>
</head>

<body>
<div id="blue"></div>
<div id="green"></div>
</body>
</html>

这样试试
------解决方案--------------------
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
#blue{
height:200px;
background-color:#00F;
position:relative;
}
#green{
height:200px;
background-color:#0F0;
}
</style>
<script type="text/javascript">
function init(){
var b=document.getElementById("blue");
var g=document.getElementById("green");
hides(b,g);
}
function getTop(obj){
var style="";
if(document.defaultView&&document.defaultView.getComputedStyle){
style=document.defaultView.getComputedStyle(obj);
}else{
style=obj.currentStyle;
}
return style.top=="auto"?obj.offsetTop:style.top;
}
function hides(b,g){
var bw=getTop(b);
var gw=getTop(g);
//alert(bw+":"+gw);
//b.style.height=parseInt(bw)+2+"px";
//g.style.height=parseInt(gw)-2+"px";
b.style.top=parseInt(bw)+2+"px";
var p=window.setTimeout(function(){hides(b,g)},100);
if(parseInt(gw)<=parseInt(bw)+8){
window.clearTimeout(p);
}
}
window.onload=init;
</script>
</head>

<body>
<div id="blue"></div>
<div id="green"></div>
</body>
</html>
这样试试