<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
ul{
width:100%;height:30px;list-style: none;position: fixed; background-color: #ccc;
}
ul li{
width: 20%;
height: 30px;
line-height: 30px;
text-align: center;
float: left;
}
</style>
</head>
<body>
<ul>
<li>1</li>
<li>2</li>
<li>3</li>
<li>4</li>
<li>5</li>
</ul>
<div data-index="0" class="x" style="width:100px; height:500px"></div>
<div id="div1" class="x" data-index="1" style="width:100%; height:250px; background:red;">
</div>
<div id="div2" class="x" data-index="2" style="width:100%; height:100px; background:blue;"> </div>
<script type="text/javascript" src="jquery-1.7.2.js"></script>
<script type="text/javascript">
// 返回浏览器的可视区域位置
function getClient() {
var l, t, w, h;
l = document.documentElement.scrollLeft || document.body.scrollLeft;
t = document.documentElement.scrollTop || document.body.scrollTop;
w = document.documentElement.clientWidth;
h = document.documentElement.clientHeight;
return {
left: l,
top: t,
width: w,
height: h
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// 返回待加载资源位置
function getSubClient(p) {
var l = 0,
t = 0,
w, h;
w = p.offsetWidth;
h = p.offsetHeight;
while (p.offsetParent) {
l += p.offsetLeft;
t += p.offsetTop;
p = p.offsetParent;
}
return {
left: l,
top: t,
width: w,
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};
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// 判断两个矩形是否相交,返回一个布尔值
function intens(rec1, rec2) {
var lc1, lc2, tc1, tc2, w1, h1;
lc1 = rec1.left + rec1.width / 2;
lc2 = rec2.left + rec2.width / 2;
tc1 = rec1.top + rec1.height / 2;
tc2 = rec2.top + rec2.height / 2;
w1 = (rec1.width + rec2.width) / 2;
h1 = (rec1.height + rec2.height) / 2;
return Math.abs(lc1 - lc2) < w1 && Math.abs(tc1 - tc2) < h1;
}
$(".x").each(function(){
var index = $(this).attr('data-index');
var rec1 = getClient();
var rec2 = getSubClient($(this)[0]);
if(intens(rec1, rec2)){
$("ul li:eq("+index+")").css({
background: '#FF0000'
});
$("ul li:eq("+index+")").siblings('li').css({
background: '#ccc'
});
}
});
window.onscroll = function() {
$(".x").each(function(){
var index = $(this).attr('data-index');
var rec1 = getClient();
var rec2 = getSubClient($(this)[0]);
if(intens(rec1, rec2)){
$("ul li:eq("+index+")").css({
background: '#FF0000'
});
$("ul li:eq("+index+")").siblings('li').css({
background: '#ccc'
});
}
});
}
</script>
</body>
</html>
