Bootstrap组件

三、Bootstrap组件

1 Glyphicons 字体图标

图标类不能和其它组件直接联合使用。它们不能在同一个元素上与其他类共同存在。应该创建一个嵌套的 <span> 标签，并将图标类应用到这个 <span> 标签上。

图标类只能应用在不包含任何文本内容或子元素的元素上。

<button type="button" class="btn btn-default" aria-label="Left Align">
  <span class="glyphicon glyphicon-align-left" aria-hidden="true"></span>
</button>

<button type="button" class="btn btn-default btn-lg">
  <span class="glyphicon glyphicon-star" aria-hidden="true"></span> Star
</button>

<div class="alert alert-danger" role="alert">
  <span class="glyphicon glyphicon-exclamation-sign" aria-hidden="true"></span>
  <span class="sr-only">Error:</span>
  Enter a valid email address
</div>

2 下拉菜单

2.1 基本使用

<div class="dropdown">
  <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu1" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true">
    Dropdown
    <span class="caret"></span>
  </button>
  <ul class="dropdown-menu" aria-labelledby="dropdownMenu1">
    <li><a href="#">Action</a></li>
    <li><a href="#">Another action</a></li>
    <li><a href="#">Something else here</a></li>
    <li role="separator" class="divider"></li>
    <li><a href="#">Separated link</a></li>
  </ul>
</div>

通过为下拉菜单的父元素设置 .dropup 类，可以让菜单向上弹出（默认是向下弹出的）

<div class="dropup"> ... </div>

2.2 对齐

默认情况下，下拉菜单自动沿着父元素的上沿和左侧被定位为 100% 宽度。 为 .dropdown-menu 添加 .dropdown-menu-right 类可以让菜单右对齐。

<ul class="dropdown-menu dropdown-menu-right" aria-labelledby="dLabel">
  ...
</ul>

2.3 标题

在任何下拉菜单中均可通过添加标题来标明一组动作。

<ul class="dropdown-menu" aria-labelledby="dropdownMenu3">
  ...
  <li class="dropdown-header">Dropdown header</li>
  ...
</ul>

2.4 分割线

为下拉菜单添加一条分割线，用于将多个链接分组

<ul class="dropdown-menu" aria-labelledby="dropdownMenuDivider">
  ...
  <li role="separator" class="divider"></li>
  ...
</ul>

2.5 禁用的菜单项

为下拉菜单中的 <li> 元素添加 .disabled 类，从而禁用相应的菜单项

3 按钮组

3.1 基本使用

<div class="btn-group" role="group" aria-label="...">
  <button type="button" class="btn btn-default">Left</button>
  <button type="button" class="btn btn-default">Middle</button>
  <button type="button" class="btn btn-default">Right</button>
</div>

3.2 按钮工具栏

把多个按钮组 嵌套在一个工具栏里面

<div class="btn-toolbar" role="toolbar" aria-label="...">
  <div class="btn-group" role="group" aria-label="...">...</div>
  <div class="btn-group" role="group" aria-label="...">...</div>
  <div class="btn-group" role="group" aria-label="...">...</div>
</div>

3.3 尺寸

只要给 .btn-group 加上 .btn-group-* 类，就省去为按钮组中的每个按钮都赋予尺寸类了，如果包含了多个按钮组时也适用

<div class="btn-group btn-group-lg" role="group" aria-label="...">...</div>
<div class="btn-group" role="group" aria-label="...">...</div>
<div class="btn-group btn-group-sm" role="group" aria-label="...">...</div>
<div class="btn-group btn-group-xs" role="group" aria-label="...">...</div>

3.4 嵌套下拉菜单

想要把下拉菜单混合到一系列按钮中，只须把 .btn-group 放入另一个 .btn-group 中

<div class="btn-group" role="group" aria-label="...">
  <button type="button" class="btn btn-default">1</button>
  <button type="button" class="btn btn-default">2</button>

  <div class="btn-group" role="group">
    <button type="button" class="btn btn-default dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
      Dropdown
      <span class="caret"></span>
    </button>
    <ul class="dropdown-menu">
      <li><a href="#">Dropdown link</a></li>
      <li><a href="#">Dropdown link</a></li>
    </ul>
  </div>
</div>

3.5 垂直排列

让一组按钮垂直堆叠排列显示而不是水平排列

<div class="btn-group-vertical" role="group" aria-label="...">
  ...
</div>

3.6 两端对齐排列的按钮组

元素

只须将一系列 .btn 元素包裹到 .btn-group.btn-group-justified 中即可

<div class="btn-group btn-group-justified" role="group" aria-label="...">
  ...
</div>

元素

<div class="btn-group btn-group-justified" role="group" aria-label="...">
  <div class="btn-group" role="group">
    <button type="button" class="btn btn-default">Left</button>
  </div>
  <div class="btn-group" role="group">
    <button type="button" class="btn btn-default">Middle</button>
  </div>
  <div class="btn-group" role="group">
    <button type="button" class="btn btn-default">Right</button>
  </div>
</div>

4 按钮式下拉菜单

前面的下拉菜单，重点介绍下拉菜单。 本部分介绍下拉菜单的按钮

4.1 单按钮下拉菜单

<!-- Single button -->
<div class="btn-group">
  <button type="button" class="btn btn-default dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
    Action <span class="caret"></span>
  </button>
  <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 role="separator" class="divider"></li>
    <li><a href="#">Separated link</a></li>
  </ul>
</div>

4.2 分列式按钮下拉菜单

<!-- Split button -->
<div class="btn-group">
  <button type="button" class="btn btn-danger">Action</button>
  <button type="button" class="btn btn-danger dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
    <span class="caret"></span>
    <span class="sr-only">Toggle Dropdown</span>
  </button>
  <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 role="separator" class="divider"></li>
    <li><a href="#">Separated link</a></li>
  </ul>
</div>

4.3 尺寸

按钮式下拉菜单适用所有尺寸的按钮。

<!-- Large button group -->
<div class="btn-group">
  <button class="btn btn-default btn-lg dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
    Large button <span class="caret"></span>
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>

<!-- Small button group -->
<div class="btn-group">
  <button class="btn btn-default btn-sm dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
    Small button <span class="caret"></span>
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>

<!-- Extra small button group -->
<div class="btn-group">
  <button class="btn btn-default btn-xs dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
    Extra small button <span class="caret"></span>
  </button>
  <ul class="dropdown-menu">
    ...
  </ul>
</div>

4.4 向上弹出菜单

给父元素添加 .dropup 类就能使触发的下拉菜单朝上方打开。

<div class="btn-group dropup">
  <button type="button" class="btn btn-default">Dropup</button>
  <button type="button" class="btn btn-default dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
    <span class="caret"></span>
    <span class="sr-only">Toggle Dropdown</span>
  </button>
  <ul class="dropdown-menu">
    <!-- Dropdown menu links -->
  </ul>
</div>

5 输入框组

通过在文本输入框 <input> 前面、后面或是两边加上文字或按钮，可以实现对表单控件的扩展。为 .input-group 赋予 .input-group-addon 或 .input-group-btn 类，可以给 .form-control 的前面或后面添加额外的元素。

5.1 基本使用

<div class="input-group">
  <span class="input-group-addon" id="basic-addon1">@</span>
  <input type="text" class="form-control" placeholder="Username" aria-describedby="basic-addon1">
</div>

<div class="input-group">
  <input type="text" class="form-control" placeholder="Recipient's username" aria-describedby="basic-addon2">
  <span class="input-group-addon" id="basic-addon2">@example.com</span>
</div>

<div class="input-group">
  <span class="input-group-addon">$</span>
  <input type="text" class="form-control" aria-label="Amount (to the nearest dollar)">
  <span class="input-group-addon">.00</span>
</div>

<label for="basic-url">Your vanity URL</label>
<div class="input-group">
  <span class="input-group-addon" id="basic-addon3">https://example.com/users/</span>
  <input type="text" class="form-control" id="basic-url" aria-describedby="basic-addon3">
</div>

5.2 尺寸

<div class="input-group input-group-lg">
  <span class="input-group-addon" id="sizing-addon1">@</span>
  <input type="text" class="form-control" placeholder="Username" aria-describedby="sizing-addon1">
</div>

<div class="input-group">
  <span class="input-group-addon" id="sizing-addon2">@</span>
  <input type="text" class="form-control" placeholder="Username" aria-describedby="sizing-addon2">
</div>

<div class="input-group input-group-sm">
  <span class="input-group-addon" id="sizing-addon3">@</span>
  <input type="text" class="form-control" placeholder="Username" aria-describedby="sizing-addon3">
</div>

5.3 作为额外元素的多选框和单选框

 <div class="input-group">
      <span class="input-group-addon">
        <input type="checkbox" aria-label="...">
      </span>
      <input type="text" class="form-control" aria-label="...">
</div><!-- /input-group -->

<div class="input-group">
      <span class="input-group-addon">
        <input type="radio" aria-label="...">
      </span>
      <input type="text" class="form-control" aria-label="...">
</div><!-- /input-group -->

5.4 作为额外元素的按钮

<div class="input-group">
    <span class="input-group-btn">
        <button class="btn btn-default" type="button">Go!</button>
    </span>
    <input type="text" class="form-control" placeholder="Search for...">
</div><!-- /input-group -->

<div class="input-group">
    <input type="text" class="form-control" placeholder="Search for...">
    <span class="input-group-btn">
        <button class="btn btn-default" type="button">Go!</button>
    </span>
</div><!-- /input-group -->

5.5 作为额外元素的按钮式下拉菜单

<div class="input-group">
    <div class="input-group-btn">
        <button type="button" class="btn btn-default dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Action <span class="caret"></span></button>
        <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 role="separator" class="divider"></li>
            <li><a href="#">Separated link</a></li>
        </ul>
    </div><!-- /btn-group -->
    <input type="text" class="form-control" aria-label="...">
</div><!-- /input-group -->

5.6 作为额外元素的分裂式按钮下拉菜单

<div class="input-group">
  <div class="input-group-btn">
    <!-- Button and dropdown menu -->
  </div>
  <input type="text" class="form-control" aria-label="...">
</div>

<div class="input-group">
  <input type="text" class="form-control" aria-label="...">
  <div class="input-group-btn">
    <!-- Button and dropdown menu -->
  </div>
</div>

5.7 一个方向多个按钮

<div class="input-group">
  <div class="input-group-btn">
    <!-- Buttons -->
  </div>
  <input type="text" class="form-control" aria-label="...">
</div>

<div class="input-group">
  <input type="text" class="form-control" aria-label="...">
  <div class="input-group-btn">
    <!-- Buttons -->
  </div>
</div>

6 导航Tab

6.1 标签页

<ul class="nav nav-tabs">
  <li role="presentation" class="active"><a href="#">Home</a></li>
  <li role="presentation"><a href="#">Profile</a></li>
  <li role="presentation"><a href="#">Messages</a></li>
</ul>

6.2 胶囊式标签页

<ul class="nav nav-pills">
  <li role="presentation" class="active"><a href="#">Home</a></li>
  <li role="presentation"><a href="#">Profile</a></li>
  <li role="presentation"><a href="#">Messages</a></li>
</ul>

胶囊式标签页垂直

<ul class="nav nav-pills nav-stacked">
  ...
</ul>

6.3 两端对齐的标签页

<ul class="nav nav-tabs nav-justified">
  ...
</ul>
<ul class="nav nav-pills nav-justified">
  ...
</ul>

6.4 禁用的链接

对任何导航组件（标签页、胶囊式标签页），都可以添加 .disabled 类，从而实现链接为灰色且没有鼠标悬停效果。

6.5 带下拉菜单的标签页

<ul class="nav nav-tabs">
  ...
  <li role="presentation" class="dropdown">
    <a class="dropdown-toggle" data-toggle="dropdown" href="#" role="button" aria-haspopup="true" aria-expanded="false">
      Dropdown <span class="caret"></span>
    </a>
    <ul class="dropdown-menu">
      ...
    </ul>
  </li>
  ...
</ul>

<!--胶囊式标签页-->
<ul class="nav nav-pills">
  ...
  <li role="presentation" class="dropdown">
    <a class="dropdown-toggle" data-toggle="dropdown" href="#" role="button" aria-haspopup="true" aria-expanded="false">
      Dropdown <span class="caret"></span>
    </a>
    <ul class="dropdown-menu">
      ...
    </ul>
  </li>
  ...
</ul>

7 导航条

7.1 基本使用

<nav class="navbar navbar-default">
  <div class="container-fluid">
    <!-- Brand and toggle get grouped for better mobile display -->
    <div class="navbar-header">
      <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1" 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="#">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 <span class="sr-only">(current)</span></a></li>
        <li><a href="#">Link</a></li>
        <li class="dropdown">
          <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">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 role="separator" class="divider"></li>
            <li><a href="#">Separated link</a></li>
            <li role="separator" class="divider"></li>
            <li><a href="#">One more separated link</a></li>
          </ul>
        </li>
      </ul>
      <form class="navbar-form navbar-left">
        <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" role="button" aria-haspopup="true" aria-expanded="false">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 role="separator" class="divider"></li>
            <li><a href="#">Separated link</a></li>
          </ul>
        </li>
      </ul>
    </div><!-- /.navbar-collapse -->
  </div><!-- /.container-fluid -->
</nav>

7.2 品牌图标

将导航条内放置品牌标志的地方替换为 <img> 元素即可展示自己的品牌图标。由于 .navbar-brand 已经被设置了内补（padding）和高度（height），你需要根据自己的情况添加一些 CSS 代码从而覆盖默认设置。

<nav class="navbar navbar-default">
  <div class="container-fluid">
    <div class="navbar-header">
      <a class="navbar-brand" href="#">
        <img alt="Brand" src="...">
      </a>
    </div>
  </div>
</nav>

7.3 表单

将表单放置于 .navbar-form 之内可以呈现很好的垂直对齐，并在较窄的视口（viewport）中呈现折叠状态。 使用对齐选项可以规定其在导航条上出现的位置。

<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>

7.4 按钮

对于不包含在 <form> 中的 <button> 元素，加上 .navbar-btn 后，可以让它在导航条里垂直居中

<button type="button" class="btn btn-default navbar-btn">Sign in</button>

7.5 文本

把文本包裹在 .navbar-text中时，为了有正确的行距和颜色，通常使用 <p> 标签

<p class="navbar-text">Signed in as Mark Otto</p>

7.6 非导航的链接

或许你希望在标准的导航组件之外添加标准链接，那么，使用 .navbar-link 类可以让链接有正确的默认颜色和反色设置

<p class="navbar-text navbar-right">Signed in as <a href="#" class="navbar-link">Mark Otto</a></p>

7.7 组件排列

通过添加 .navbar-left 和 .navbar-right 工具类让导航链接、表单、按钮或文本对齐。两个类都会通过 CSS 设置特定方向的浮动样式。例如，要对齐导航链接，就要把它们放在个分开的、应用了工具类的 <ul>标签里。

7.8 固定在顶部

添加 .navbar-fixed-top 类可以让导航条固定在顶部，还可包含一个 .container 或 .container-fluid容器，从而让导航条居中，并在两侧添加内补（padding）。

<nav class="navbar navbar-default navbar-fixed-top">
  <div class="container">
    ...
  </div>
</nav>

7.9 固定在底部

添加 .navbar-fixed-bottom 类可以让导航条固定在底部，并且还可以包含一个 .container 或 .container-fluid 容器，从而让导航条居中，并在两侧添加内补（padding)

<nav class="navbar navbar-default navbar-fixed-bottom">
  <div class="container">
    ...
  </div>
</nav>

7.10 静止在顶部

<nav class="navbar navbar-default navbar-static-top">
  <div class="container">
    ...
  </div>
</nav>

7.11 反色

<nav class="navbar navbar-inverse">
  ...
</nav>

8 路径导航

面包屑导航

<ol class="breadcrumb">
  <li><a href="#">Home</a></li>
  <li><a href="#">Library</a></li>
  <li class="active">Data</li>
</ol>

9 分页

9.1 默认分页

<nav aria-label="Page navigation">
  <ul class="pagination">
    <li>
      <a href="#" aria-label="Previous">
        <span aria-hidden="true">&laquo;</span>
      </a>
    </li>
    <li><a href="#">1</a></li>
    <li><a href="#">2</a></li>
    <li><a href="#">3</a></li>
    <li><a href="#">4</a></li>
    <li><a href="#">5</a></li>
    <li>
      <a href="#" aria-label="Next">
        <span aria-hidden="true">&raquo;</span>
      </a>
    </li>
  </ul>
</nav>

禁用和激活状态

你可以给不能点击的链接添加 .disabled 类、给当前页添加 .active 类

我们建议将 active 或 disabled 状态的链接（即 <a> 标签）替换为 <span> 标签，或者在向前/向后的箭头处省略<a> 标签，这样就可以让其保持需要的样式而不能被点击。

<nav aria-label="...">
  <ul class="pagination">
    <li class="disabled">
      <span>
        <span aria-hidden="true">&laquo;</span>
      </span>
    </li>
    <li class="active">
      <span>1 <span class="sr-only">(current)</span></span>
    </li>
    ...
  </ul>
</nav>

尺寸

<nav aria-label="..."><ul class="pagination pagination-lg">...</ul></nav>
<nav aria-label="..."><ul class="pagination">...</ul></nav>
<nav aria-label="..."><ul class="pagination pagination-sm">...</ul></nav>

9.2 翻页

基本使用

<nav aria-label="...">
  <ul class="pager">
    <li><a href="#">Previous</a></li>
    <li><a href="#">Next</a></li>
  </ul>
</nav>

对齐链接

<nav aria-label="...">
  <ul class="pager">
    <li class="previous"><a href="#"><span aria-hidden="true">&larr;</span> Older</a></li>
    <li class="next"><a href="#">Newer <span aria-hidden="true">&rarr;</span></a></li>
  </ul>
</nav>

可选的禁用状态

<nav aria-label="...">
  <ul class="pager">
    <li class="previous disabled"><a href="#"><span aria-hidden="true">&larr;</span> Older</a></li>
    <li class="next"><a href="#">Newer <span aria-hidden="true">&rarr;</span></a></li>
  </ul>
</nav>

10 标签

10.1 基本使用

<h3>Example heading <span class="label label-default">New</span></h3>

10.2 各种颜色的标签

<span class="label label-default">Default</span>
<span class="label label-primary">Primary</span>
<span class="label label-success">Success</span>
<span class="label label-info">Info</span>
<span class="label label-warning">Warning</span>
<span class="label label-danger">Danger</span>

11 徽章

给链接、导航等元素嵌套 <span class="badge"> 元素，可以很醒目的展示新的或未读的信息条目。

<a href="#">Inbox <span class="badge">42</span></a>

<button class="btn btn-primary" type="button">
  Messages <span class="badge">4</span>
</button>

<ul class="nav nav-pills" role="tablist">
  <li role="presentation" class="active"><a href="#">Home <span class="badge">42</span></a></li>
  <li role="presentation"><a href="#">Profile</a></li>
  <li role="presentation"><a href="#">Messages <span class="badge">3</span></a></li>
</ul>

12 巨幕

<div class="jumbotron">
  <h1>Hello, world!</h1>
  <p>...</p>
  <p><a class="btn btn-primary btn-lg" href="#" role="button">Learn more</a></p>
</div>

如果需要让巨幕组件的宽度与浏览器宽度一致并且没有圆角，请把此组件放在所有 .container 元素的外面，并在组件内部添加一个 .container 元素。

<div class="jumbotron">
  <div class="container">
    ...
  </div>
</div>

13 页头

页头组件能够为 h1 标签增加适当的空间，并且与页面的其他部分形成一定的分隔。它支持 h1 标签内内嵌 small 元素的默认效果，还支持大部分其他组件（需要增加一些额外的样式）

<div class="page-header">
  <h1>Example page header <small>Subtext for header</small></h1>
</div>

14 缩略图

14.1 基本样式

<div class="row">
  <div class="col-xs-6 col-md-3">
    <a href="#" class="thumbnail">
      <img src="..." alt="...">
    </a>
  </div>
  ...
</div>

14.2 带内容的缩略图

<div class="row">
  <div class="col-sm-6 col-md-4">
    <div class="thumbnail">
      <img src="..." alt="...">
      <div class="caption">
        <h3>Thumbnail label</h3>
        <p>...</p>
        <p><a href="#" class="btn btn-primary" role="button">Button</a> <a href="#" class="btn btn-default" role="button">Button</a></p>
      </div>
    </div>
  </div>
</div>

15 警告框

15.1 基本用法

<div class="alert alert-success" role="alert">...</div>
<div class="alert alert-info" role="alert">...</div>
<div class="alert alert-warning" role="alert">...</div>
<div class="alert alert-danger" role="alert">...</div>

15.2 可关闭的警告框

为警告框添加一个可选的 .alert-dismissible 类和一个关闭按钮。

<div class="alert alert-warning alert-dismissible" role="alert">
  <button type="button" class="close" data-dismiss="alert" aria-label="Close"><span aria-hidden="true">&times;</span></button>
  <strong>Warning!</strong> Better check yourself, you're not looking too good.
</div>

15.3 警告框中的链接

用 .alert-link 工具类，可以为链接设置与当前警告框相符的颜色。

<div class="alert alert-success" role="alert">
  <a href="#" class="alert-link">...</a>
</div>
<div class="alert alert-info" role="alert">
  <a href="#" class="alert-link">...</a>
</div>
<div class="alert alert-warning" role="alert">
  <a href="#" class="alert-link">...</a>
</div>
<div class="alert alert-danger" role="alert">
  <a href="#" class="alert-link">...</a>
</div>

16进度条

16.1 基本使用

<div class="progress">
  <div class="progress-bar" role="progressbar" style="width: 60%;">
  </div>
</div>

16.2 带有提示标签的进度条

将设置了 .sr-only 类的 <span> 标签从进度条组件中移除 类，从而让当前进度显示出来。

<div class="progress">
  <div class="progress-bar" role="progressbar" aria-valuenow="60" aria-valuemin="0" aria-valuemax="100" style="width: 60%;">
    60%
  </div>
</div>

在展示很低的百分比时，如果需要让文本提示能够清晰可见，可以为进度条设置 min-width 属性。

16.3进度条颜色

<div class="progress">
  <div class="progress-bar progress-bar-success" role="progressbar" aria-valuenow="40" aria-valuemin="0" aria-valuemax="100" style="width: 40%">
    <span class="sr-only">40% Complete (success)</span>
  </div>
</div>

<div class="progress">
  <div class="progress-bar progress-bar-info" role="progressbar" aria-valuenow="20" aria-valuemin="0" aria-valuemax="100" style="width: 20%">
    <span class="sr-only">20% Complete</span>
  </div>
</div>

<div class="progress">
  <div class="progress-bar progress-bar-warning" role="progressbar" aria-valuenow="60" aria-valuemin="0" aria-valuemax="100" style="width: 60%">
    <span class="sr-only">60% Complete (warning)</span>
  </div>
</div>

<div class="progress">
  <div class="progress-bar progress-bar-danger" role="progressbar" aria-valuenow="80" aria-valuemin="0" aria-valuemax="100" style="width: 80%">
    <span class="sr-only">80% Complete (danger)</span>
  </div>
</div>

16.4 条纹效果

<div class="progress">
  <div class="progress-bar progress-bar-success progress-bar-striped" role="progressbar" aria-valuenow="40" aria-valuemin="0" aria-valuemax="100" style="width: 40%">
    <span class="sr-only">40% Complete (success)</span>
  </div>
</div>

<div class="progress">
  <div class="progress-bar progress-bar-info progress-bar-striped" role="progressbar" aria-valuenow="20" aria-valuemin="0" aria-valuemax="100" style="width: 20%">
    <span class="sr-only">20% Complete</span>
  </div>
</div>

<div class="progress">
  <div class="progress-bar progress-bar-warning progress-bar-striped" role="progressbar" aria-valuenow="60" aria-valuemin="0" aria-valuemax="100" style="width: 60%">
    <span class="sr-only">60% Complete (warning)</span>
  </div>
</div>

<div class="progress">
  <div class="progress-bar progress-bar-danger progress-bar-striped" role="progressbar" aria-valuenow="80" aria-valuemin="0" aria-valuemax="100" style="width: 80%">
    <span class="sr-only">80% Complete (danger)</span>
  </div>
</div>

16.5 动画效果

为 .progress-bar-striped 添加 .active 类，使其呈现出由右向左运动的动画效果。IE9 及更低版本的浏览器不支持

<div class="progress">
  <div class="progress-bar progress-bar-striped active" role="progressbar" aria-valuenow="45" aria-valuemin="0" aria-valuemax="100" style="width: 45%">
    <span class="sr-only">45% Complete</span>
  </div>
</div>

16.7 堆叠效果

<div class="progress">
  <div class="progress-bar progress-bar-success" style="width: 35%">
    <span class="sr-only">35% Complete (success)</span>
  </div>
  <div class="progress-bar progress-bar-warning progress-bar-striped" style="width: 20%">
    <span class="sr-only">20% Complete (warning)</span>
  </div>
  <div class="progress-bar progress-bar-danger" style="width: 10%">
    <span class="sr-only">10% Complete (danger)</span>
  </div>
</div>

17 媒体对象

这是一个抽象的样式，用以构建不同类型的组件，这些组件都具有在文本内容的左或右侧对齐的图片（就像博客评论或 Twitter 消息等）。

17.1 默认样式

<div class="media">
  <div class="media-left">
    <a href="#">
      <img class="media-object" src="..." alt="...">
    </a>
  </div>
  <div class="media-body">
    <h4 class="media-heading">Media heading</h4>
    ...
  </div>
</div>

17.2 对齐

图片或其他媒体类型可以顶部、中部或底部对齐。默认是顶部对齐。

<div class="media">
  <div class="media-left media-middle">
    <a href="#">
      <img class="media-object" src="..." alt="...">
    </a>
  </div>
  <div class="media-body">
    <h4 class="media-heading">Middle aligned media</h4>
    ...
  </div>
</div>

17.3 媒体对象列表

<ul class="media-list">
  <li class="media">
    <div class="media-left">
      <a href="#">
        <img class="media-object" src="..." alt="...">
      </a>
    </div>
    <div class="media-body">
      <h4 class="media-heading">Media heading</h4>
      ...
    </div>
  </li>
</ul>

18 列表组

18.1 基本使用

<ul class="list-group">
  <li class="list-group-item">Cras justo odio</li>
  <li class="list-group-item">Dapibus ac facilisis in</li>
  <li class="list-group-item">Morbi leo risus</li>
  <li class="list-group-item">Porta ac consectetur ac</li>
  <li class="list-group-item">Vestibulum at eros</li>
</ul>

18.2 带徽章

<ul class="list-group">
  <li class="list-group-item">
    <span class="badge">14</span>
    Cras justo odio
  </li>
</ul>

18.3 列表

<div class="list-group">
  <a href="#" class="list-group-item active">
    Cras justo odio
  </a>
  <a href="#" class="list-group-item">Dapibus ac facilisis in</a>
  <a href="#" class="list-group-item">Morbi leo risus</a>
  <a href="#" class="list-group-item">Porta ac consectetur ac</a>
  <a href="#" class="list-group-item">Vestibulum at eros</a>
</div>

18.4 按钮

<div class="list-group">
  <button type="button" class="list-group-item">Cras justo odio</button>
  <button type="button" class="list-group-item">Dapibus ac facilisis in</button>
  <button type="button" class="list-group-item">Morbi leo risus</button>
  <button type="button" class="list-group-item">Porta ac consectetur ac</button>
  <button type="button" class="list-group-item">Vestibulum at eros</button>
</div>

18.5 被禁用的条目

<div class="list-group">
  <a href="#" class="list-group-item disabled">
    Cras justo odio
  </a>
  <a href="#" class="list-group-item">Dapibus ac facilisis in</a>
  <a href="#" class="list-group-item">Morbi leo risus</a>
  <a href="#" class="list-group-item">Porta ac consectetur ac</a>
  <a href="#" class="list-group-item">Vestibulum at eros</a>
</div>

18.6 情景类(颜色)

<ul class="list-group">
  <li class="list-group-item list-group-item-success">Dapibus ac facilisis in</li>
  <li class="list-group-item list-group-item-info">Cras sit amet nibh libero</li>
  <li class="list-group-item list-group-item-warning">Porta ac consectetur ac</li>
  <li class="list-group-item list-group-item-danger">Vestibulum at eros</li>
</ul>

18.7 定制内容

列表组中的每个元素都可以是任何 HTML 内容，甚至是像下面的带链接的列表组。

<div class="list-group">
  <a href="#" class="list-group-item active">
    <h4 class="list-group-item-heading">List group item heading</h4>
    <p class="list-group-item-text">...</p>
  </a>
</div>

19 面板

19.1 基本

<div class="panel panel-default">
  <div class="panel-body">
    Basic panel example
  </div>
</div>

19.2 带标题的面板

<div class="panel panel-default">
  <div class="panel-heading">Panel heading without title</div>
  <div class="panel-body">
    Panel content
  </div>
</div>

<div class="panel panel-default">
  <div class="panel-heading">
    <h3 class="panel-title">Panel title</h3>
  </div>
  <div class="panel-body">
    Panel content
  </div>
</div>

19.3 带脚注的面板

<div class="panel panel-default">
  <div class="panel-body">
    Panel content
  </div>
  <div class="panel-footer">Panel footer</div>
</div>

19.4 情境效果

<div class="panel panel-primary">...</div>
<div class="panel panel-success">...</div>
<div class="panel panel-info">...</div>
<div class="panel panel-warning">...</div>
<div class="panel panel-danger">...</div>

19.5 带表格的面板

<div class="panel panel-default">
  <!-- Default panel contents -->
  <div class="panel-heading">Panel heading</div>
  <div class="panel-body">
    <p>...</p>
  </div>

  <!-- Table -->
  <table class="table">
    ...
  </table>
</div>

如果没有 .panel-body ，面版标题会和表格连接起来，没有空隙

<div class="panel panel-default">
  <!-- Default panel contents -->
  <div class="panel-heading">Panel heading</div>

  <!-- Table -->
  <table class="table">
    ...
  </table>
</div>

19.6 带列表组的面板

<div class="panel panel-default">
  <!-- Default panel contents -->
  <div class="panel-heading">Panel heading</div>
  <div class="panel-body">
    <p>...</p>
  </div>

  <!-- List group -->
  <ul class="list-group">
    <li class="list-group-item">Cras justo odio</li>
    <li class="list-group-item">Dapibus ac facilisis in</li>
    <li class="list-group-item">Morbi leo risus</li>
    <li class="list-group-item">Porta ac consectetur ac</li>
    <li class="list-group-item">Vestibulum at eros</li>
  </ul>
</div>

20 具有响应式特性的嵌入内容

根据被嵌入内容的外部容器的宽度，自动创建一个固定的比例，从而让浏览器自动确定视频或 slideshow 的尺寸，能够在各种设备上缩放。

这些规则被直接应用在 <iframe>、<embed>、<video> 和 <object> 元素上。如果你希望让最终样式与其他属性相匹配，还可以明确地使用一个派生出来的 .embed-responsive-item 类。

超级提示： 不需要为 <iframe> 元素设置 frameborder="0" 属性，因为我们已经替你这样做了！

<!-- 16:9 aspect ratio -->
<div class="embed-responsive embed-responsive-16by9">
  <iframe class="embed-responsive-item" src="..."></iframe>
</div>

<!-- 4:3 aspect ratio -->
<div class="embed-responsive embed-responsive-4by3">
  <iframe class="embed-responsive-item" src="..."></iframe>
</div>

21 Well

21.1 默认样式

<div class="well">...</div>

21.2 尺寸

<div class="well well-lg">...</div>
<div class="well well-sm">...</div>

#