在我的，指示它是一个下拉菜单的箭头显示在菜单上，但当我悬停或点击它不显示我的下拉链接。我认为我已经包括所有必要的类，我不相信Twitter的需要javascript。

你能看到我做错了吗？

我的下拉菜单

<div class='topbar' data-dropdown="dropdown">

  <div class='fill'>
    <div class='container'>
    <ul class="nav">

      <li><%= link_to 'Home',main_app.root_path %></li>
          <li><%= link_to 'Outlines',main_app.outlines_path %></li>
       <li class="dropdown">
        <a href="#" class="dropdown-toggle">Assessment</a>
        <ul class="dropdown-menu">
        <li><a href="#">second link </a></li>
        <li><a href="#">third link </a></li>
        </ul>
      </li>

  ..... I go on to close all the divs etc. The nav bar looks great but the dropdown just doesn't work.

Twitter Bootstrap

<div class="topbar" data-dropdown="dropdown">
  <div class="topbar-inner">
    <div class="container">
      <h3><a href="#">Project Name</a></h3>
      <ul class="nav">
        <li class="active"><a href="#">Home</a></li>
        <li><a href="#">Link</a></li>
        <li><a href="#">Link</a></li>
        <li><a href="#">Link</a></li>
        <li class="dropdown">
          <a href="#" class="dropdown-toggle">Dropdown</a>
          <ul class="dropdown-menu">
            <li><a href="#">Secondary link</a></li>
            <li><a href="#">Something else here</a></li>
            <li class="divider"></li>
            <li><a href="#">Another link</a></li>
          </ul>
        </li>
      </ul>
      <form class="pull-left" action="">
        <input type="text" placeholder="Search">
      </form>
      <ul class="nav secondary-nav">
        <li class="dropdown">
          <a href="#" class="dropdown-toggle">Dropdown</a>
          <ul class="dropdown-menu">
            <li><a href="#">Secondary link</a></li>
            <li><a href="#">Something else here</a></li>
            <li class="divider"></li>
            <li><a href="#">Another link</a></li>
          </ul>
        </li>
      </ul>
    </div>
  </div><!-- /topbar-inner -->
</div>