JS模拟的QQ面板上的多级可展开的菜单_导航菜单

<title>QQ菜单</title> <script> if (!document.getElementById) document.getElementById = function() { return null; } function initializeMenu(menuId, actuatorId) { var menu = document.getElementById(menuId); var actuator = document.getElementById(actuatorId); if (menu == null || actuator == null) return; actuator.parentNode.style.backgroundImage = "url(/images/plus.gif)"; actuator.onclick = function() { var display = menu.style.display; this.parentNode.style.backgroundImage = (display == "block") ? "url(/images/plus.gif)" : "url(/images/minus.gif)"; menu.style.display = (display == "block") ? "none" : "block"; return false; } } window.onload = function() { initializeMenu("productsMenu", "productsActuator"); initializeMenu("newPhonesMenu", "newPhonesActuator"); initializeMenu("compareMenu", "compareActuator"); } </script> <style> body { font-family: verdana, helvetica, arial, sans-serif; } #mainMenu { background-color: #EEE; border: 1px solid #CCC; color: #000; width: 203px; } #menuList { margin: 0px; padding: 10px 0px 10px 15px; } li.menubar { background: url() no-repeat 0em 0.3em; font-size: 12px; line-height: 1.5em; list-style: none outside; } .menu, .submenu { display: none; margin-left: 15px; padding: 0px; } .menu li, .submenu li { background: url() no-repeat 0em 0.3em; list-style: none outside; } a.actuator { background-color: transparent; color: #000; font-size: 12px; padding-left: 15px; text-decoration: none; } a.actuator:hover { text-decoration: underline; } .menu li a, .submenu li a { background-color: transparent; color: #000; font-size: 12px; padding-left: 15px; text-decoration: none; } .menu li a:hover, submenu li a:hover { text-decoration: underline; } span.key { text-decoration: underline; } </style> <div id="mainMenu"> <ul id="menuList"> <li class="menubar"> <a href="#" id="productsActuator" class="actuator">我有朋友圈</a> <ul id="productsMenu" class="menu"> <li> <a href="#" id="newPhonesActuator" class="actuator">我的好友</a> <ul id="newPhonesMenu" class="submenu"> <li><a href="#">张三[10000001]</a></li> <li><a href="#">李四[10000002]</a></li> <li><a href="#">李四[10000002]</a></li> </ul> </li> <li> <a href="#" id="compareActuator" class="actuator">陌生人</a> <ul id="compareMenu" class="submenu"> <li><a href="#">张三[10000001]</a></li> <li><a href="#">李四[10000002]</a></li> </ul> </li> </ul> </li> </ul> </div>