如何使用jQuery技术开发ios风格的页面导航菜单

<nav><h1>导航菜单</h1><ul><li><h2>专题教程</h2><ul><li><h3>HTML专题教程</h3><ul><li><a href="http://www.gbin1.com/tutorials/html5-tutorial/html5-introduction">GBin1专题之HTML5教程 - 第一篇：HTML5介绍</a></li><li><a href="http://www.gbin1.com/tutorials/html5-tutorial/html5-new-elements">GBin1专题之HTML5教程 - 第二篇：HTML5元素</a></li><li><a href="http://www.gbin1.com/tutorials/html5-tutorial/html5-video">GBin1专题之HTML5教程 - 第三篇：HTML5 Video元素</a></li><li><a href="http://www.gbin1.com/tutorials/html5-tutorial/html5-video-doc">GBin1专题之HTML5教程 - 第四篇：HTML5 Video Doc</a></li><li><a href="http://www.gbin1.com/tutorials/html5-tutorial/html5-audio">GBin1专题之HTML5教程 - 第五篇：HTML5 Audio元素</a></li></ul><li><h3>GBin1热点秀</h3><ul><li><a href="http://www.gbin1.com/tutorials/hotspot/hotspot1/">GBin1专题之Web热点秀#1</a><li><a href="http://www.gbin1.com/tutorials/hotspot/hotspot2/">GBin1专题之Web热点秀#2</a><li><a href="http://www.gbin1.com/tutorials/hotspot/hotspot3/">GBin1专题之Web热点秀#3</a></ul> </ul>

$(function(){ var nav = $("nav"),navTitle = nav.children().first(),navTitleLabel = navTitle.text(),mainList = navTitle.next(),subLevels = mainList.find("ul"),hiddenClass = "hidden"; nav.addClass("js");mainList.find("a:last-child").addClass("files");subLevels.addClass(hiddenClass); navTitle.wrap($("<div/>")).before($("<a/>", {href: "#",className: hiddenClass,click: function(e){var $this = $(this),activeList = subLevels.filter(":visible:last"),activeListParents = activeList.parents("ul");navTitle.text($this.text());if(activeListParents.length > 2)$this.text(activeListParents.eq(1).prev().text());else if (activeListParents.length > 1)$this.text(navTitleLabel)else$this.addClass(hiddenClass).empty();setTimeout(function(){activeList.addClass(hiddenClass);}, slideDuration - 100);mainList.css("left", parseInt(mainList.css("left")) + navWidth + "px");e.preventDefault();}})); subLevels.prev().wrap($("<a/>", {href:"#",click: function(e){var $this = $(this);backArrow.removeClass(hiddenClass).text(navTitle.text());navTitle.text($this.text());$this.next().removeClass(hiddenClass);mainList.css("left", parseInt(mainList.css("left")) - navWidth + "px");e.preventDefault();}})); var backArrow = navTitle.prev(),navWidth = nav.width(),firstSubLevel = subLevels.eq(0),docStyle = document.documentElement.style,slideDuration = 0,timingRatio = 1000; if(docStyle.WebkitTransition !== undefined)slideDuration = parseFloat(firstSubLevel.css("-webkit-transition-duration")) * timingRatio; if(docStyle.MozTransition !== undefined)slideDuration = parseFloat(firstSubLevel.css("-moz-transition-duration")) * timingRatio; if(docStyle.OTransition !== undefined)slideDuration = parseFloat(firstSubLevel.css("-o-transition-duration")) * timingRatio; });

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