引导程序3中折叠的下拉菜单丢失了吗？

Question

我升级到引导3，在我的资产净值有一个简单的下拉菜单（http://bootply.com/73584）：

<div class="navbar"> 
    <div class="container"> 

    <!-- .navbar-toggle is used as the toggle for collapsed navbar content --> 
    <button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-responsive-collapse"> 
     <span class="icon-bar"></span> 
     <span class="icon-bar"></span> 
     <span class="icon-bar"></span> 
    </button> 

    <!-- Be sure to leave the brand out there if you want it shown --> 
    <a class="navbar-brand" href="#">Title</a> 

    <!-- Place everything within .nav-collapse to hide it until above 768px --> 
    <div class="nav-collapse collapse navbar-responsive-collapse"> 

    <ul class="nav navbar-nav"> 
    <li class="active"><a href="#">Home</a></li> 
    <li><a href="#">Link</a></li> 

    <li class="dropdown"> 
      <a class="dropdown-toggle" data-toggle="dropdown" href="#"> 
      Dropdown <span class="caret"></span> 
      </a> 
      <ul class="dropdown-menu"> 
      <li><a href="#">Action</a></li> 
      <li><a href="#">Another action</a></li> 
      <li><a href="#">Something else here</a></li> 
      <li class="divider"></li> 
      <li><a href="#">Separated link</a></li> 
      </ul> 
     </li> 



    </ul> 

    </div><!-- /.nav-collapse --> 
    </div><!-- /.container --> 
</div><!-- /.navbar --> 

在折叠手机，查看下拉仍然弹出;它不会像Bootstrap 2中那样添加子菜单子项。这是缺失还是故意的？任何人都知道我可以如何添加bootstrap 2行为？

感谢

Answer 1

你是正确的，我不知道这是这个缺失或故意（参见：https://github.com/twbs/bootstrap/issues/9253）。

您可以应用在Twitter的引导2，样式规则：

@media (max-width: 979px) 
{ 
    .nav-collapse .dropdown-menu a { 
    padding: 9px 15px; 
    font-weight: bold; 
    color: #777777; 
    -webkit-border-radius: 3px; 
     -moz-border-radius: 3px; 
      border-radius: 3px; 
    } 
    .nav-collapse .btn { 
    padding: 4px 10px 4px; 
    font-weight: normal; 
    -webkit-border-radius: 4px; 
     -moz-border-radius: 4px; 
      border-radius: 4px; 
    } 
    .nav-collapse .dropdown-menu li + li a { 
    margin-bottom: 2px; 
    } 

    .nav-collapse .dropdown-menu a:hover, 
    .nav-collapse .dropdown-menu a:focus { 
    background-color: #f2f2f2; 
    } 

    .navbar-inverse .nav-collapse .dropdown-menu a:hover, 
    .navbar-inverse .nav-collapse .dropdown-menu a:focus { 
    background-color: #111111; 
    } 
    .nav-collapse.in .btn-group { 
    padding: 0; 
    margin-top: 5px; 
    } 
    .nav-collapse .dropdown-menu { 
    position: static; 
    top: auto; 
    left: auto; 
    display: none; 
    float: none; 
    max-width: none; 
    padding: 0; 
    margin: 0 15px; 
    background-color: transparent; 
    border: none; 
    -webkit-border-radius: 0; 
     -moz-border-radius: 0; 
      border-radius: 0; 
    -webkit-box-shadow: none; 
     -moz-box-shadow: none; 
      box-shadow: none; 
    } 
    .nav-collapse .open > .dropdown-menu { 
    display: block; 
    } 
    .nav-collapse .dropdown-menu:before, 
    .nav-collapse .dropdown-menu:after { 
    display: none; 
    } 
    .nav-collapse .dropdown-menu .divider { 
    display: none; 
    } 
    .nav-collapse .nav > li > .dropdown-menu:before, 
    .nav-collapse .nav > li > .dropdown-menu:after { 
    display: none; 
    } 
} 

请参见：http://bootply.com/73740的结果。