Twitter Bootstrap:如何实现始终折叠的导航栏下拉菜单？

Question

我在Twitter Bootstrap中使用Navbar组件

http://getbootstrap.com/components/#navbar

我的目标是让导航栏始终折叠(即使在桌面大小的设备上查看).如何才能做到这一点？

到目前为止,我已经用我的代码创建了这个JSFIDDLE - 你会发现它非常标准.当结果窗口的大小很小时,下拉菜单将折叠.但是,如果放大结果窗口,则下拉列表不会折叠.

我已经准确地粘贴了JSFiddle中的内容以供参考:

<nav class="navbar navbar-default" role="navigation">
  <div class="container-fluid">
    <!-- Brand and toggle get grouped for better mobile display -->
    <div class="navbar-header">
      <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1">
        <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="#">Brand</a>
    </div>

    <!-- Collect the nav links, forms, and other content for toggling -->
    <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
      <ul class="nav navbar-nav">
        <li class="active"><a href="#">Link</a></li>
        <li><a href="#">Link</a></li>
        <li class="dropdown">
          <a href="#" class="dropdown-toggle" data-toggle="dropdown">Dropdown <b class="caret"></b></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>
            <li class="divider"></li>
            <li><a href="#">One more separated link</a></li>
          </ul>
        </li>
      </ul>
      <form class="navbar-form navbar-left" role="search">
        <div class="form-group">
          <input type="text" class="form-control" placeholder="Search">
        </div>
        <button type="submit" class="btn btn-default">Submit</button>
      </form>
      <ul class="nav navbar-nav navbar-right">
        <li><a href="#">Link</a></li>
        <li class="dropdown">
          <a href="#" class="dropdown-toggle" data-toggle="dropdown">Dropdown <b class="caret"></b></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><!-- /.navbar-collapse -->
  </div><!-- /.container-fluid -->
</nav>

Answer 1

基本上有两种方法可以实现您想要的:重新定义与导航栏折叠相关的CSS规则并重新编译Bootstrap的LESS.

如果你对LESS一无所知,第一种方式似乎更容易,但它确实不是最好的方式.您必须搜索受折叠导航栏事件影响的所有 CSS规则.关闭我的头顶,我能想到的,将改为三个规则:.navbar-header,.navbar-collapse.collapse和.navbar-toggle:

@media (min-width: 768px)
{
    .navbar-header
    {
        float: none;
    }

    .navbar-toggle
    {
        display: block;
    }

    .navbar-collapse.collapse
    {
        display: none !important;
    }
}

这是一个基于你的小提琴的例子.

另一种方法是更改@grid-float-breakpoint位于variables.less文件中的变量.为此,您必须下载Bootstrap源代码,并在更改所需的变量后,您必须重新编译您的LESS.

这可能是实现目标的最佳方式,因为它是一个"全局"解决方案,并且不需要任何CSS覆盖.

Answer 2

You can always create a right-aligned (navbar-right) drop-down (dropdown, dropdown-toggle, dropdown-menu) menu with a hamburger glyph (glyphicon-menu-hamburger) in it.

Example:

<ul class="nav navbar-nav navbar-right">
    <li class="dropdown">
        <a class="dropdown-toggle" data-toggle="dropdown" href="#">
            <span class="glyphicon glyphicon-menu-hamburger"></span>
        </a>
        <ul class="dropdown-menu">
            <li><a href="#">Hamburger 1</a></li>
            <li><a href="#">Hamburger 2</a></li>
            <li><a href="#">Hamburger 3</a></li>
        </ul>
    </li>
</ul>

I don't like how the hamburger becomes left-aligned on smaller screens. Other than that this works.