jquery树形菜单加个图片会的加QQ给我讲一下

<script src="js/jquery-1.3.2.min.js" type="text/javascript"></script>
    <style>
        a{
            text-decoration:none;
        }

    </style>
    <script type="text/javascript">
        $(document).ready(function() {
            //让所有的子节点折叠
           $("ul ul").hide();
            $("li:has(ul) > a").css("cursor", "hand").click(function() {
                //找到a旁边的ul
                var ul = $(this).parent().find("ul");
                //判断ul状态
                //                if (ul.is(":hidden")) {
                //                    ul.show();
                //                }
                //                else {
                //                    ul.hide();
                //                }
                //toggle方法：元素显示则隐藏，隐藏则显示
                ul.toggle();
                return false;
            });
            $("li:not(:has(ul)) > a").css({cursor:"hand","list-style":"url(2222.jpg)"});        });
    
    </script>
</head>
<body>
    <div>
        <ul>
            <li>
                <a href="#">文档管理</a>
                <ul>
                    <li>
                        <a href="#">文档上传</a>
                    </li>
                    <li>
                        <a href="#">文档共享</a>
                    </li>
                </ul>
            </li>
             <li>
                <a href="#">公告管理</a>
                <ul>
                    <li>
                        <a href="#">公告发布</a>
                    </li>
                    <li>
                        <a href="#">公告浏览</a>
                    </li>
                </ul>
            </li>
            <li>
                <a href="#">公告管理</a>
                <ul>
                    <li>
                        <a href="#">公告发布</a>
                    </li>
                    <li>
                        <a href="#">公告浏览</a>
                    </li>
                </ul>
            </li>
            <li>
                <a href="#">公告管理</a>
                <ul>
                    <li>
                        <a href="#">公告发布</a>
                    </li>
                    <li>
                        <a href="#">公告浏览</a>
                    </li>
                </ul>
            </li>
        </ul>
    </div>
</body>加QQ给我讲一下50301402  急用谢谢了