如何将具有垂直子菜单的水平菜单转换为具有子菜单的垂直手风琴菜单？

Question

我想制作我的菜单，以便当我处于特定的窗口大小（如手机）时，我的菜单将转换为垂直下拉式手风琴菜单。我对媒体查询和响应/自适应设计很熟悉，但我无法让我的子菜单垂直放下/下滑，无论是悬停还是点击。

这里是我的Fiddle

HTML：

<!--MENU UNDER HEADER BEGINS--> 
<table id="menubar" width="0" border="0" align="center" cellpadding="0" cellspacing="0"> 
    <tr> 
    <td> 

    <div id="navmenu"> <!--#navmenu DIV menu contents start here--> 
    <ul> 

<li>  
    <a href="index.php" class="mainlist">HOME</a> 
</li> 

<li> 
    <a href="about.php" class="mainlist">ABOUT ME</a> 
</li> 




<li class="slidedown">  
    <a href="graphicdesign.php" class="mainlist">GRAPHIC DESIGN</a> 
    <ul> 
    <li><a href="graphicdesign/hobbyist-independent.php">Hobbyist/Independent</a></li>  
    <li><a href="graphicdesign/job&amp;freelance.php">Job & FreeLance</a></li> 
    <li><a href="graphicdesign/universityatbuffalo.php">University At Buffalo</a></li> 
    </ul> 
</li> 


<li class="slidedown"> 
    <a href="webdesign.php" class="mainlist">WEB DESIGN</a> 
    <ul> 
    <li>Hobbyist/Independent</li> 
    <li>Job & FreeLance</li> 
    <li>University At Buffalo Website</a></li> 
    </ul> 
</li> 


<li class="slidedown"> 
    <a href="photography.php" class="mainlist">PHOTOGRAPHY</a> 
    <ul> 
    <li><a href="photography/hobbyist-independent.php">Hobbyist/Independent</a></li> 
    <li><a href="photography/job&amp;freelance.php">Job & Freelance</a></li> 
    <li><a href="photography/studentprojects.php">Student Projects</a></li> 
    </ul> 
</li> 


<li> 
    <a href="contactme.php" class="mainlist">CONTACT ME</a> 
</li> 

    </ul> 
    </div> <!--#navmenu DIV menu contents end here--> 

    </td> 
    </tr> 
</table> 
<!--menu under header ends--> 

CSS：

html, body { 
    height: 100%; 
    overflow-x:hidden; 
    overflow-y:hidde; 
    margin:auto; 
} 
#wrap { 
    margin:auto; 
    min-height: 100%; 
    background-image: url(style/flourish-bg.png); 
    background-repeat:no-repeat; 
    background-position: top center; 
    z-index:0; 
} 
#header { 
    width:1024px; 
    height:160px; 
    background-repeat: no-repeat; 
} 
#bgheader { 
    background-image: url(style/bgheader.jpg); 
    background-repeat:repeat-x; 
    height:160px; 
} 
body { 
    margin-left: 0px; 
    margin-top: 0px; 
    margin-right: 0px; 
    background-repeat: no-repeat; 
    background:#000; 
} 

/*----------MENU-----------*/ 


/*main menu*/ 

a:link {color:#fff; text-decoration:none;} 
a:visited {color: #868D65;} 
a:hover {color:#000;} 
a:active {color: #868D65;} 

#navmenu { 
    width:100%; 
    height:80px; 
    margin-right:auto; 
    margin-left:auto; 
} 

/*holds the listed items on main menu*/ 
#navmenu ul { 
    width:100%; 
    margin:0; 
    padding: 0; 
    list-style:none; 
    text-decoration:none; 
} 

/*keeps main menu horiztonal, and effects the actualy list items, overrides any other menu float*/ 
#navmenu li { 
    float:left; 
    padding: 30px 7px; 
    position:relative; 
    list-style:none; 
    text-decoration:none; 
    font-family: Georgia, "Times New Roman", Times, serif; 
    font-size:12px; 
    text-decoration: none; 
    border-top: 2px solid #868D65; 
    border-bottom: 2px solid #868D65; 
    transition: border-radius 1s, background 1s; 
    -moz-transition: -moz-border-radius 1s, background 1s; 
    -webkit-transition: -webkit-border-radius 1s, background 1s; 
    z-index:200; 
} 

/*menu styling for hover, WHEN IMAGE IS ADDED, IT APPLIES TO ALL HOVER ACTIONS ON EVERY MENU*/ 
#navmenu li:hover { 
    background: #eee; 
    background-image: url(style/bgheader.jpg); 
    transition: border-radius 1s, background 1s; 
-moz-transition: -moz-border-radius 1s, background 1s; 
-webkit-transition: -webkit-border-radius 1s, background 1s; 
z-index:200; 
} 
/*SUB MENU STARTS*/ 


/*this hides the submenu*/ 
#navmenu li ul { 
    position: absolute; 
    top:75px; 
    visibility:hidden; 
    padding-left:0px; 
} 
/*this shows the submenu on hover over main menu*/ 
#navmenu li:hover ul {visibility:visible;} 

/*sub menu styling*/ 
#navmenu li ul li { 
    float:none; 
    width: 160px; 
    font-size:12px; 
    text-align:center; 
    padding: 15px 5px 10px 5px; 
    background: #222222; 
    border: 1px solid #FFF; 
    color: #FFF; 
    position:relative; 
    margin-left: -6px; 
} 

/*sub menu styling for hover*/ 
#navmenu li ul li:hover { 
    font-size:12px; 
    color: #000; 
    background-color: #868D65; 
} 

Answer 1

Here you go

@media (max-width:600px) { 
    tr td #navmenu li { 
    width:100%; // makes each item takes up the whole screen 
    } 
    tr td #navmenu li ul { 
    position:relative !important; // removes the position absolute so that it doesn't overlap the higher up menu items 
    top:0; // puts it right next to the menu item 
    display:none; // so there is no unnecessary white space when the `li` isn't being hovered over 
    } 
    tr td #navmenu li:hover ul { 
    display:block; // shows the submenu when you hover over the higher `li`s 
    } 
} 

Answer 2

把这样的事情在你的手机布局的媒体查询

#navmenu li { 
    display: block; 
    text-align: center; 
    float:none; 
} 

#navmenu li ul { 
    display: none; 
    position: relative; 
    top:0; 
    visibility:hidden; 
} 

，因为你的T关于如何显示子菜单echnique是纯CSS（：对父母和知名度悬停：可见），我们需要JS/jQuery的，因为我们的孩子菜单显示：无现

$('li.slidedown').hover(function() { 
    $(this).find('ul').slideDown(); 
}, function() { 
    $(this).find('ul').slideUp(); 
}); 

还没有检查了我的代码，BYT我希望你得到我的点