定位（Position）
相对窗口、文档、锚、光标/鼠标等元素定位一个元素。
如需了解更多有关 .position() 方法的细节，请查看 API 文档 .position()。
默认功能
使用表单控件配置位置，或者拖拽被定位的元素来修改它的偏移量。向四周拖拽父元素来查看碰撞检测。
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>jQuery UI 定位（Position） - 默认功能</title>
<link rel="stylesheet" href="//code.jquery.com/ui/1.10.4/themes/smoothness/jquery-ui.css">
<script src="//code.jquery.com/jquery-1.9.1.js"></script>
<script src="//code.jquery.com/ui/1.10.4/jquery-ui.js"></script>
<link rel="stylesheet" href="http://jqueryui.com/resources/demos/style.css">
<style>
#parent {
width: 60%;
height: 40px;
margin: 10px auto;
padding: 5px;
border: 1px solid #777;
background-color: #fbca93;
text-align: center;
}
.positionable {
position: absolute;
display: block;
right: 0;
bottom: 0;
background-color: #bcd5e6;
text-align: center;
}
#positionable1 {
width: 75px;
height: 75px;
}
#positionable2 {
width: 120px;
height: 40px;
}
select, input {
margin-left: 15px;
}
</style>
<script>
$(function() {
function position() {
$( ".positionable" ).position({
of: $( "#parent" ),
my: $( "#my_horizontal" ).val() + " " + $( "#my_vertical" ).val(),
at: $( "#at_horizontal" ).val() + " " + $( "#at_vertical" ).val(),
collision: $( "#collision_horizontal" ).val() + " " + $( "#collision_vertical" ).val()
});
}
$( ".positionable" ).css( "opacity", 0.5 );
$( "select, input" ).bind( "click keyup change", position );
$( "#parent" ).draggable({
drag: position
});
position();
});
</script>
</head>
<body>
<div id="parent">
<p>
这是父元素的位置。
</p>
</div>
<div class="positionable" id="positionable1">
<p>
to position
</p>
</div>
<div class="positionable" id="positionable2">
<p>
to position 2
</p>
</div>
<div style="padding: 20px; margin-top: 75px;">
定位...
<div style="padding-bottom: 20px;">
<b>my:</b>
<select id="my_horizontal">
<option value="left">left</option>
<option value="center">center</option>
<option value="right">right</option>
</select>
<select id="my_vertical">
<option value="top">top</option>
<option value="center">center</option>
<option value="bottom">bottom</option>
</select>
</div>
<div style="padding-bottom: 20px;">
<b>at:</b>
<select id="at_horizontal">
<option value="left">left</option>
<option value="center">center</option>
<option value="right">right</option>
</select>
<select id="at_vertical">
<option value="top">top</option>
<option value="center">center</option>
<option value="bottom">bottom</option>
</select>
</div>
<div style="padding-bottom: 20px;">
<b>collision:</b>
<select id="collision_horizontal">
<option value="flip">flip</option>
<option value="fit">fit</option>
<option value="flipfit">flipfit</option>
<option value="none">none</option>
</select>
<select id="collision_vertical">
<option value="flip">flip</option>
<option value="fit">fit</option>
<option value="flipfit">flipfit</option>
<option value="none">none</option>
</select>
</div>
</div>
</body>
</html>
图像循环
一个照片浏览器的原型，使用 Position 分别把图片定为在左边、中间、右边，然后循环显示。使用顶部的链接来循环图像，或者在图像的左侧或右侧点击来循环图像。请注意，当调整窗口大小时，会重新定位图像。
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>jQuery UI 定位（Position） - 图像循环</title>
<link rel="stylesheet" href="//code.jquery.com/ui/1.10.4/themes/smoothness/jquery-ui.css">
<script src="//code.jquery.com/jquery-1.9.1.js"></script>
<script src="//code.jquery.com/ui/1.10.4/jquery-ui.js"></script>
<link rel="stylesheet" href="http://jqueryui.com/resources/demos/style.css">
<style>
body {
margin: 0;
}
#container {
overflow: hidden;
position: relative;
height: 400px;
}
img {
position: absolute;
}
</style>
<script>
$(function() {
// 重构部件，去除这些插件方法
$.fn.left = function( using ) {
return this.position({
my: "right middle",
at: "left+25 middle",
of: "#container",
collision: "none",
using: using
});
};
$.fn.right = function( using ) {
return this.position({
my: "left middle",
at: "right-25 middle",
of: "#container",
collision: "none",
using: using
});
};
$.fn.center = function( using ) {
return this.position({
my: "center middle",
at: "center middle",
of: "#container",
using: using
});
};
$( "img:eq(0)" ).left();
$( "img:eq(1)" ).center();
$( "img:eq(2)" ).right();
function animate( to ) {
$( this ).stop( true, false ).animate( to );
}
function next( event ) {
event.preventDefault();
$( "img:eq(2)" ).center( animate );
$( "img:eq(1)" ).left( animate );
$( "img:eq(0)" ).right().appendTo( "#container" );
}
function previous( event ) {
event.preventDefault();
$( "img:eq(0)" ).center( animate );
$( "img:eq(1)" ).right( animate );
$( "img:eq(2)" ).left().prependTo( "#container" );
}
$( "#previous" ).click( previous );
$( "#next" ).click( next );
$( "img" ).click(function( event ) {
$( "img" ).index( this ) === 0 ? previous( event ) : next( event );
});
$( window ).resize(function() {
$( "img:eq(0)" ).left( animate );
$( "img:eq(1)" ).center( animate );
$( "img:eq(2)" ).right( animate );
});
});
</script>
</head>
<body>
<div id="container">
<img src="/wp-content/uploads/2014/03/earth.jpg" width="458" height="308" alt="earth">
<img src="/wp-content/uploads/2014/03/flight.jpg" width="512" height="307" alt="flight">
<img src="/wp-content/uploads/2014/03/rocket.jpg" width="300" height="353" alt="rocket">
<a id="previous" href="#">上一个</a>
<a id="next" href="#">下一个</a>
</div>
</body>
</html>