<divclass="alert alert-danger"role="alert"><spanclass="glyphicon glyphicon-exclamation-sign"aria-hidden="true"></span><spanclass="sr-only">Error:</span>
Enter a valid email address
If the <a> elements are used to act as buttons – triggering in-page functionality, rather than navigating to another document or section within the current page – they should also be given an appropriate role="button".
关于 <button> 元素
为了将 <button> 元素用于两端对齐的按钮组中,必须将每个按钮包裹进一个按钮组中you must wrap each button in a button group。大部分的浏览器不能将我们的 CSS 应用到对齐的 <button> 元素上,但是,由于我们支持按钮式下拉菜单,我们可以解决这个问题。
<!-- Large button group --><divclass="btn-group"><buttonclass="btn btn-default btn-lg dropdown-toggle"type="button"data-toggle="dropdown"aria-haspopup="true"aria-expanded="false">
Large button <spanclass="caret"></span></button><ulclass="dropdown-menu"><!-- Small button group --><divclass="btn-group"><buttonclass="btn btn-default btn-sm dropdown-toggle"type="button"data-toggle="dropdown"aria-haspopup="true"aria-expanded="false">
Small button <spanclass="caret"></span></button><ulclass="dropdown-menu"><!-- Extra small button group --><divclass="btn-group"><buttonclass="btn btn-default btn-xs dropdown-toggle"type="button"data-toggle="dropdown"aria-haspopup="true"aria-expanded="false">
Extra small button <spanclass="caret"></span></button><ulclass="dropdown-menu">
Screen readers will have trouble with your forms if you don't include a label for every input. For these input groups, ensure that any additional label or functionality is conveyed to assistive technologies.
The exact technique to be used (visible <label> elements, <label> elements hidden using the .sr-only class, or use of the aria-label, aria-labelledby, aria-describedby, title or placeholder attribute) and what additional information will need to be conveyed will vary depending on the exact type of interface widget you're implementing. The examples in this section provide a few suggested, case-specific approaches.
<!-- Button and dropdown menu --><inputtype="text"class="form-control"aria-label="..."><divclass="input-group"><inputtype="text"class="form-control"aria-label="..."><divclass="input-group-btn"><!-- Button and dropdown menu -->
Multiple buttons
While you can only have one add-on per side, you can have multiple buttons inside a single .input-group-btn.
<navclass="navbar navbar-default"><divclass="container-fluid"><!-- Brand and toggle get grouped for better mobile display --><divclass="navbar-header"><buttontype="button"class="navbar-toggle collapsed"data-toggle="collapse"data-target="#bs-example-navbar-collapse-1"aria-expanded="false"><spanclass="sr-only">Toggle navigation</span><spanclass="icon-bar"></span><spanclass="icon-bar"></span><spanclass="icon-bar"></span></button><aclass="navbar-brand"href="#">Brand</a><!-- Collect the nav links, forms, and other content for toggling --><divclass="collapse navbar-collapse"id="bs-example-navbar-collapse-1"><ulclass="nav navbar-nav"><liclass="active"><ahref="#">Link <spanclass="sr-only">(current)</span></a></li><li><ahref="#">Link</a></li><liclass="dropdown"><ahref="#"class="dropdown-toggle"data-toggle="dropdown"role="button"aria-haspopup="true"aria-expanded="false">Dropdown <spanclass="caret"></span></a><ulclass="dropdown-menu"><li><ahref="#">Action</a></li><li><ahref="#">Another action</a></li><li><ahref="#">Something else here</a></li><lirole="separator"class="divider"></li><li><ahref="#">Separated link</a></li><lirole="separator"class="divider"></li><li><ahref="#">One more separated link</a></li><formclass="navbar-form navbar-left"><divclass="form-group"><inputtype="text"class="form-control"placeholder="Search"><buttontype="submit"class="btn btn-default">Submit</button></form><ulclass="nav navbar-nav navbar-right"><li><ahref="#">Link</a></li><liclass="dropdown"><ahref="#"class="dropdown-toggle"data-toggle="dropdown"role="button"aria-haspopup="true"aria-expanded="false">Dropdown <spanclass="caret"></span></a><ulclass="dropdown-menu"><li><ahref="#">Action</a></li><li><ahref="#">Another action</a></li><li><ahref="#">Something else here</a></li><lirole="separator"class="divider"></li><li><ahref="#">Separated link</a></li></div><!-- /.navbar-collapse --></div><!-- /.container-fluid -->
与 .navbar-fixed-* 类不同的是,你不用给 body 添加任何内补(padding)。
Labelling the pagination component
The pagination component should be wrapped in a <nav> element to identify it as a navigation section to screen readers and other assistive technologies. In addition, as a page is likely to have more than one such navigation section already (such as the primary navigation in the header, or a sidebar navigation), it is advisable to provide a descriptive aria-label for the <nav> which reflects its purpose. For example, if the pagination component is used to navigate between a set of search results, an appropriate label could be aria-label="Search results pages".
Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.
Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.
Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.
进度条组件使用了 CSS3 的 transition 和 animation 属性来完成一些特效。这些特性在 Internet Explorer 9 或以下版本中、Firefox 的老版本中没有被支持。Opera 12 不支持 animation 属性。
Content Security Policy (CSP) compatibility
If your website has a Content Security Policy (CSP) which doesn't allow style-src 'unsafe-inline', then you won't be able to use inline style attributes to set progress bar widths as shown in our examples below. Alternative methods for setting the widths that are compatible with strict CSPs include using a little custom JavaScript (that sets element.style.width) or using custom CSS classes.
Cras sit amet nibh libero, in gravida nulla. Nulla vel metus scelerisque ante sollicitudin commodo. Cras purus odio, vestibulum in vulputate at, tempus viverra turpis. Fusce condimentum nunc ac nisi vulputate fringilla. Donec lacinia congue felis in faucibus.
Donec sed odio dui. Nullam quis risus eget urna mollis ornare vel eu leo. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus.
Middle aligned media
Cras sit amet nibh libero, in gravida nulla. Nulla vel metus scelerisque ante sollicitudin commodo. Cras purus odio, vestibulum in vulputate at, tempus viverra turpis. Fusce condimentum nunc ac nisi vulputate fringilla. Donec lacinia congue felis in faucibus.
Donec sed odio dui. Nullam quis risus eget urna mollis ornare vel eu leo. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus.
Bottom aligned media
Cras sit amet nibh libero, in gravida nulla. Nulla vel metus scelerisque ante sollicitudin commodo. Cras purus odio, vestibulum in vulputate at, tempus viverra turpis. Fusce condimentum nunc ac nisi vulputate fringilla. Donec lacinia congue felis in faucibus.
Donec sed odio dui. Nullam quis risus eget urna mollis ornare vel eu leo. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus.
<ulclass="list-group"><liclass="list-group-item">Cras justo odio</li><liclass="list-group-item">Dapibus ac facilisis in</li><liclass="list-group-item">Morbi leo risus</li><liclass="list-group-item">Porta ac consectetur ac</li><liclass="list-group-item">Vestibulum at eros</li>
给列表组加入徽章组件,它会自动被放在右边。
Cras justo odio
Dapibus ac facilisis in
Morbi leo risus
<divclass="list-group"><ahref="#"class="list-group-item active">
Cras justo odio
<ahref="#"class="list-group-item">Dapibus ac facilisis in</a><ahref="#"class="list-group-item">Morbi leo risus</a><ahref="#"class="list-group-item">Porta ac consectetur ac</a><ahref="#"class="list-group-item">Vestibulum at eros</a>
<divclass="list-group"><buttontype="button"class="list-group-item">Cras justo odio</button><buttontype="button"class="list-group-item">Dapibus ac facilisis in</button><buttontype="button"class="list-group-item">Morbi leo risus</button><buttontype="button"class="list-group-item">Porta ac consectetur ac</button><buttontype="button"class="list-group-item">Vestibulum at eros</button>
<divclass="list-group"><ahref="#"class="list-group-item disabled">
Cras justo odio
<ahref="#"class="list-group-item">Dapibus ac facilisis in</a><ahref="#"class="list-group-item">Morbi leo risus</a><ahref="#"class="list-group-item">Porta ac consectetur ac</a><ahref="#"class="list-group-item">Vestibulum at eros</a>
<ulclass="list-group"><liclass="list-group-item list-group-item-success">Dapibus ac facilisis in</li><liclass="list-group-item list-group-item-info">Cras sit amet nibh libero</li><liclass="list-group-item list-group-item-warning">Porta ac consectetur ac</li><liclass="list-group-item list-group-item-danger">Vestibulum at eros</li><divclass="list-group"><ahref="#"class="list-group-item list-group-item-success">Dapibus ac facilisis in</a><ahref="#"class="list-group-item list-group-item-info">Cras sit amet nibh libero</a><ahref="#"class="list-group-item list-group-item-warning">Porta ac consectetur ac</a><ahref="#"class="list-group-item list-group-item-danger">Vestibulum at eros</a>
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。
List group item heading
Donec id elit non mi porta gravida at eget metus. Maecenas sed diam eget risus varius blandit.
List group item heading
Donec id elit non mi porta gravida at eget metus. Maecenas sed diam eget risus varius blandit.
List group item heading
Donec id elit non mi porta gravida at eget metus. Maecenas sed diam eget risus varius blandit.
<divclass="list-group"><ahref="#"class="list-group-item active"><h4class="list-group-item-heading">List group item heading</h4><pclass="list-group-item-text">...</p>
虽然不总是必须,但是某些时候你可能需要将某些 DOM 内容放到一个盒子里。对于这种情况,可以试试面板组件。
Some default panel content here. Nulla vitae elit libero, a pharetra augue. Aenean lacinia bibendum nulla sed consectetur. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum. Nullam id dolor id nibh ultricies vehicula ut id elit.
Some default panel content here. Nulla vitae elit libero, a pharetra augue. Aenean lacinia bibendum nulla sed consectetur. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum. Nullam id dolor id nibh ultricies vehicula ut id elit.
<divclass="panel panel-default"><!-- Default panel contents --><divclass="panel-heading">Panel heading</div><divclass="panel-body"><p>...</p><!-- List group --><ulclass="list-group"><liclass="list-group-item">Cras justo odio</li><liclass="list-group-item">Dapibus ac facilisis in</li><liclass="list-group-item">Morbi leo risus</li><liclass="list-group-item">Porta ac consectetur ac</li><liclass="list-group-item">Vestibulum at eros</li>