现在我知道，如果用户滚动到侧边栏的底部，那么侧边栏会变为固定状态，并在他们阅读其余主要内容时停留在用户页面上。但是现在我的固定 div 掉到了页脚中。那么，我怎样才能阻止它从父 DIV 掉到页脚中呢？
这是正在发生的事情的一个小提琴：http: //jsfiddle.net/95W8w/
这是我的 HTML 和 Javascript：
<!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>Blob.net</title>
<link rel="stylesheet" type="text/css" href="css/styles.css"/>
<!-- INCLUDE THOSE JAVASCRIPTS AT THE BOTTOM FOR SPEED-->
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8/jquery.min.js"></script>
<script src="js/jquery.sticky-scroll.min.js"></script>
<!-- STOP INCLUDING THOSE JAVASCRIPT FILES-->
<script>
$(document).ready(function() {
// Cache selectors for faster performance.
var $window = $(window),
$sidebar = $('#anchor'),
$sidebarAnchor = $('#right');
// Run this on scroll events.
$window.scroll(function() {
var window_top = $window.scrollTop();
var div_top = $sidebarAnchor.offset().top;
if (window_top > div_top) {
// Make the div sticky.
$sidebar.addClass('stick');
$sidebarAnchor.height($sidebar.height());
}
else {
// Unstick the div.
$sidebar.removeClass('stick');
$sidebarAnchor.height(0);
}
});
});
</script>
</head>
<body>
<!-- MAIN CONTAINER -->
<div id="container">
<!-- HEADER -->
<div id="header">
<div id="header_text">
<h1>This is a fancy header</h1>
</div>
</div>
<!-- END HEADER -->
<!-- MAIN CONTENT -->
<div id="left">
<div id="left_inside">
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</div>
</div>
<!-- END MAIN CONTENT -->
<!-- SIDEBAR -->
<div id="right">
<div id="anchor">
<div class="elements row1">
<ul>
<li><a href="#">Home</a></li>
<li><a href="#">About</a></li>
<li><a href="#">Contact Us</a></li>
<li><a href="#">Photos</a></li>
</ul>
</div>
<div class="elements row2">
</div>
<div class="elements row3">
</div>
<div class="elements row4">
</div>
<div class="elements row5">
</div>
</div>
</div>
<!-- END SIDEBAR -->
<div class="clear"></div>
</div><!-- END MAIN CONTAINER -->
</body>
</html>
这是我的CSS：
#container {
background-color:#CCC;
margin-top: 100px;
margin-right: auto;
margin-bottom: 100px;
margin-left: auto;
width: 1200px;
height: auto;
box-shadow: 0px 0px 10px 2px rgba(119, 119, 119, 0.75);
-moz-box-shadow: 0px 0px 10px 2px rgba(119, 119, 119, 0.75);
-webkit-box-shadow: 0px 0px 10px 2px rgba(119, 119, 119, 0.75);
}
/* HEADER CSS */
#header {
width: 100%;
height: 75px;
background-color: #FC6;
padding-top: 2px;
padding-bottom: 10px;
}
#header_text h1{
font-family: "Arial Black", Gadget, sans-serif;
margin-left: 32%;
}
/* CONTENT CSS */
#left {
width: 800px;
height: auto;
background-color: #CF9;
float: left;
}
#left_inside {
padding-left: 15px;
padding-right: 15px;
margin-bottom: 30px;
}
#left p {
font-family: "Trebuchet MS", Arial, Helvetica, sans-serif;
}
/* SIDEBAR CSS */
#right {
width: 400px;
height: auto;
background-color:#6CF;
float: right;
}
.elements {
border: 1px solid #000;
height: auto;
width: 400px;
min-height: 180px;
}
/* NAV BAR STYLES */
#right ul {
list-style-type: none;
margin-left: 25%;
}
#right ul li{
margin-top: 30px;
}
#right ul li a:link{
text-decoration: none;
font-family: "Trebuchet MS", Arial, Helvetica, sans-serif;
font-size: 18px;
color: #000;
}
#right ul li a:hover{
color: #CCC;
}
/* ROWS */
.row1 {
background-color:#930;
}
.row2 {
background-color: #633;
}
.row3 {
background-color: #C66;
}
.row4 {
background-color: #96F;
}
.row5 {
background-color: #FF0;
}
/* END SIDEBAR CSS */
.clear {
clear: both;
}
/* MAKE SIDE BAR STICKY*/
.stick {
position: fixed;
bottom: 0;
}