基本上我正试图将引导导航栏转换为工具栏。在这个工具栏上，我添加了一些带下拉的btn-groups，在媒体查询崩溃之前工作得很好。一旦它被折叠，下拉菜单就看不见了，尽管元素在那里，并且它投射出的阴影就像它在那里一样。如何在崩溃后显示这些下降?
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title> INDEX </title>
<link href="bootstrap/css/bootstrap.css" rel="stylesheet">
<link href="mycss/style.css" rel="stylesheet">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js"></script>
<script type="text/javascript" src="bootstrap/js/bootstrap.js"></script>
<script type="text/javascript" src="datepicker/js/bootstrap-datepicker.js"></script>
</head>
<body>
<nav class="navbar navbar-footer">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#footNav"aria-expanded="false">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="#">Tool Bar</a>
</div>
<div class="collapse navbar-collapse" id="footNav">
<!-- 1st btn-group (No Dropdown) -->
<div class="btn-group" role="group" aria-label="..." style="margin-right: 7px">
<button type="button" class="btn btn-default">Yesterday</button>
<button type="button" class="btn btn-default">Today</button>
<button type="button" class="btn btn-default">Tomorrow</button>
</div>
<!-- 2st btn-group doesn't work after collapse -->
<div class="btn-group" role="group" aria-label="..." style="margin-right: 7px">
<div class="btn-group dropup" role="group">
<button type="button" class="btn btn-default dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Past
<span class="caret"></span>
</button>
<ul class="dropdown-menu">
<li><a href="#">Past</a></li>
<li><a href="#">This</a></li>
<li><a href="#">Next</a></li>
</ul>
</div>
<button type="button" class="btn btn-default">W</button>
<button type="button" class="btn btn-default">M</button>
<button type="button" class="btn btn-default">3M</button>
<button type="button" class="btn btn-default">Y</button>
</div>
<!-- 3rd btn-group doesn't work after collapse -->
<div class="dropup">
<button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu2" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Date Range
<span class="caret"></span>
</button>
<ul class="dropdown-menu" aria-labelledby="dropdownMenu2">
<div class="input-group" style="padding-bottom: 4px;">
<span class="input-group-addon" >From:</span>
<input class="datepicker" style="height: 30px; width:120px; font-size: 18px; padding:10px;" name="startDate">
</div>
<div class="input-group">
<span class="input-group-addon" >To:</span>
<input class="datepicker2" style="height: 30px; width:120px; font-size: 18px; padding:10px;" name="endDate">
</div>
</ul>
</div>
</div>
</nav>
</body>
</html>
我使用标准的引导的东西除了css的变化
/*Calendar tool Bar*/
.navbar {
border-radius: 0px;
}
.dropup{
display: inline-block;
}
.dropdown-menu .input-group .input-group-addon:first-child {
width: 63px;
}
.dropdown-menu {
padding: 4px 4px 4px 4px;
min-width: 30px;
}
.navbar-footer {
background-color: #f8f8f8;
border-color: #e7e7e7;
position: fixed;
bottom: 0px;
width: 100%;
margin-bottom: 0px;
vertical-align: middle;
}
.navbar-footer .navbar-toggle:hover,
.navbar-footer .navbar-toggle:focus {
background-color: #ddd;
}
.navbar-footer .navbar-toggle {
border-color: #ddd;
}
.navbar-footer .navbar-toggle .icon-bar {
background-color: #888;
}
button {
margin-top: 8px;
}
你只需要重写bootstrap的.navbar-collapse.in类，使其可见，即使它溢出垂直
.navbar-collapse.in {
overflow-y: visible;
}