滚动监听 scrollspy.js

导航条实例

滚动监听插件是用来根据滚动条所处的位置来自动更新导航项的。如下所示,滚动导航条下面的区域并关注导航项的变化。下拉菜单中的条目也会自动高亮显示。

@fat

Ad leggings keytar, brunch id art party dolor labore. Pitchfork yr enim lo-fi before they sold out qui. Tumblr farm-to-table bicycle rights whatever. Anim keffiyeh carles cardigan. Velit seitan mcsweeney's photo booth 3 wolf moon irure. Cosby sweater lomo jean shorts, williamsburg hoodie minim qui you probably haven't heard of them et cardigan trust fund culpa biodiesel wes anderson aesthetic. Nihil tattooed accusamus, cred irony biodiesel keffiyeh artisan ullamco consequat.

@mdo

Veniam marfa mustache skateboard, adipisicing fugiat velit pitchfork beard. Freegan beard aliqua cupidatat mcsweeney's vero. Cupidatat four loko nisi, ea helvetica nulla carles. Tattooed cosby sweater food truck, mcsweeney's quis non freegan vinyl. Lo-fi wes anderson +1 sartorial. Carles non aesthetic exercitation quis gentrify. Brooklyn adipisicing craft beer vice keytar deserunt.

one

Occaecat commodo aliqua delectus. Fap craft beer deserunt skateboard ea. Lomo bicycle rights adipisicing banh mi, velit ea sunt next level locavore single-origin coffee in magna veniam. High life id vinyl, echo park consequat quis aliquip banh mi pitchfork. Vero VHS est adipisicing. Consectetur nisi DIY minim messenger bag. Cred ex in, sustainable delectus consectetur fanny pack iphone.

two

In incididunt echo park, officia deserunt mcsweeney's proident master cleanse thundercats sapiente veniam. Excepteur VHS elit, proident shoreditch +1 biodiesel laborum craft beer. Single-origin coffee wayfarers irure four loko, cupidatat terry richardson master cleanse. Assumenda you probably haven't heard of them art party fanny pack, tattooed nulla cardigan tempor ad. Proident wolf nesciunt sartorial keffiyeh eu banh mi sustainable. Elit wolf voluptate, lo-fi ea portland before they sold out four loko. Locavore enim nostrud mlkshk brooklyn nesciunt.

three

Ad leggings keytar, brunch id art party dolor labore. Pitchfork yr enim lo-fi before they sold out qui. Tumblr farm-to-table bicycle rights whatever. Anim keffiyeh carles cardigan. Velit seitan mcsweeney's photo booth 3 wolf moon irure. Cosby sweater lomo jean shorts, williamsburg hoodie minim qui you probably haven't heard of them et cardigan trust fund culpa biodiesel wes anderson aesthetic. Nihil tattooed accusamus, cred irony biodiesel keffiyeh artisan ullamco consequat.

Keytar twee blog, culpa messenger bag marfa whatever delectus food truck. Sapiente synth id assumenda. Locavore sed helvetica cliche irony, thundercats you probably haven't heard of them consequat hoodie gluten-free lo-fi fap aliquip. Labore elit placeat before they sold out, terry richardson proident brunch nesciunt quis cosby sweater pariatur keffiyeh ut helvetica artisan. Cardigan craft beer seitan readymade velit. VHS chambray laboris tempor veniam. Anim mollit minim commodo ullamco thundercats.

用法

依赖 Bootstrap 的导航组件

滚动监听插件依赖 Bootstrap 的导航组件 用于高亮显示当前激活的链接。

Resolvable ID targets required

Navbar links must have resolvable id targets. For example, a <a href="#home">home</a> must correspond to something in the DOM like <div id="home"></div>.

Non-:visible target elements ignored

Target elements that are not :visible according to jQuery will be ignored and their corresponding nav items will never be highlighted.

需要相对定位(relative positioning)

无论何种实现方式,滚动监听都需要被监听的组件是 position: relative; 即相对定位方式。大多数时候是监听 <body> 元素。When scrollspying on elements other than the <body>, be sure to have a height set and overflow-y: scroll; applied.

通过 data 属性调用

To easily add scrollspy behavior to your topbar navigation, add data-spy="scroll" to the element you want to spy on (most typically this would be the <body>). Then add the data-target attribute with the ID or class of the parent element of any Bootstrap .nav component.

body {
  position: relative;
}
<body data-spy="scroll" data-target="#navbar-example">
  ...
  <div id="navbar-example">
    <ul class="nav nav-tabs" role="tablist">
      ...
    </ul>
  </div>
  ...
</body>

通过 JavaScript 调用

在 CSS 中添加 position: relative; 之后,通过 JavaScript 代码启动滚动监听插件:

$('body').scrollspy({ target: '#navbar-example' })

方法

.scrollspy('refresh')

当使用滚动监听插件的同时在 DOM 中添加或删除元素后,你需要像下面这样调用此刷新( refresh) 方法:

$('[data-spy="scroll"]').each(function () {
  var $spy = $(this).scrollspy('refresh')
})

参数

可以通过 data 属性或 JavaScript 传递参数。对于 data 属性,其名称是将参数名附着到 data- 后面组成,例如 data-offset=""

名称 类型 默认值 描述
offset number 10 计算滚动位置时相对于顶部的偏移量(像素数)。

事件

事件类型 描述
activate.bs.scrollspy 每当一个新条目被激活后都将由滚动监听插件触发此事件。
$('#myScrollspy').on('activate.bs.scrollspy', function () {
  // do something…
})