Bootstrap scrollspy
Automatically update Bootstrap navigation or list group components based on scroll position to indicate which link is currently active in the viewport.
How it works
Scrollspy has a few requirements to function properly:
- It must be used on a Bootstrap nav component or list group.
- Scrollspy requires
position: relative;
on the element you’re spying on, usually the<body>
. - Anchors (
<a>
) are required and must point to an element with thatid
.
When successfully implemented, your nav or list group will update accordingly, moving the .active
class from one item to the next based on their associated targets.
Scrollable containers and keyboard access
If you’re making a scrollable container (other than the <body>
), be sure to have a height
set and overflow-y: scroll;
applied to it—alongside a tabindex="0"
to ensure keyboard access.
Example in navbar
Scroll the area below the navbar and watch the active class change. The dropdown items will be highlighted as well.
First heading
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Second heading
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Third heading
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Fourth heading
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Fifth heading
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
<nav id="navbar-example2" class="navbar navbar-light bg-body-tertiary px-3">
<a class="navbar-brand" href="#">Navbar</a>
<ul class="nav nav-pills">
<li class="nav-item">
<a class="nav-link" href="#scrollspyHeading1">First</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#scrollspyHeading2">Second</a>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" data-coreui-toggle="dropdown" href="#" role="button" aria-expanded="false">Dropdown</a>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="#scrollspyHeading3">Third</a></li>
<li><a class="dropdown-item" href="#scrollspyHeading4">Fourth</a></li>
<li><hr class="dropdown-divider"></li>
<li><a class="dropdown-item" href="#scrollspyHeading5">Fifth</a></li>
</ul>
</li>
</ul>
</nav>
<div data-coreui-spy="scroll" data-coreui-target="#navbar-example2" data-coreui-offset="0" class="scrollspy-example" tabindex="0">
<h4 id="scrollspyHeading1">First heading</h4>
<p>...</p>
<h4 id="scrollspyHeading2">Second heading</h4>
<p>...</p>
<h4 id="scrollspyHeading3">Third heading</h4>
<p>...</p>
<h4 id="scrollspyHeading4">Fourth heading</h4>
<p>...</p>
<h4 id="scrollspyHeading5">Fifth heading</h4>
<p>...</p>
</div>
Example with nested nav
Scrollspy also works with nested .nav
s. If a nested .nav
is .active
, its parents will also be .active
. Scroll the area next to the navbar and watch the active class change.
Item 1
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Item 1-1
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Item 1-2
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Item 2
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Item 3
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Item 3-1
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Item 3-2
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
<nav id="navbar-example3" class="navbar navbar-light bg-body-tertiary flex-column align-items-stretch p-3">
<a class="navbar-brand" href="#">Navbar</a>
<nav class="nav nav-pills flex-column">
<a class="nav-link" href="#item-1">Item 1</a>
<nav class="nav nav-pills flex-column">
<a class="nav-link ms-3 my-1" href="#item-1-1">Item 1-1</a>
<a class="nav-link ms-3 my-1" href="#item-1-2">Item 1-2</a>
</nav>
<a class="nav-link" href="#item-2">Item 2</a>
<a class="nav-link" href="#item-3">Item 3</a>
<nav class="nav nav-pills flex-column">
<a class="nav-link ms-3 my-1" href="#item-3-1">Item 3-1</a>
<a class="nav-link ms-3 my-1" href="#item-3-2">Item 3-2</a>
</nav>
</nav>
</nav>
<div data-coreui-spy="scroll" data-coreui-target="#navbar-example3" data-coreui-offset="0" tabindex="0">
<h4 id="item-1">Item 1</h4>
<p>...</p>
<h5 id="item-1-1">Item 1-1</h5>
<p>...</p>
<h5 id="item-1-2">Item 1-2</h5>
<p>...</p>
<h4 id="item-2">Item 2</h4>
<p>...</p>
<h4 id="item-3">Item 3</h4>
<p>...</p>
<h5 id="item-3-1">Item 3-1</h5>
<p>...</p>
<h5 id="item-3-2">Item 3-2</h5>
<p>...</p>
</div>
Example with list-group
Scrollspy also works with .list-group
s. Scroll the area next to the list group and watch the active class change.
Item 1
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Item 2
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Item 3
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
Item 4
This is some placeholder content for the scrollspy page. Note that as you scroll down the page, the appropriate navigation link is highlighted. It's repeated throughout the component example. We keep adding some more example copy here to emphasize the scrolling and highlighting.
<div id="list-example" class="list-group">
<a class="list-group-item list-group-item-action" href="#list-item-1">Item 1</a>
<a class="list-group-item list-group-item-action" href="#list-item-2">Item 2</a>
<a class="list-group-item list-group-item-action" href="#list-item-3">Item 3</a>
<a class="list-group-item list-group-item-action" href="#list-item-4">Item 4</a>
</div>
<div data-coreui-spy="scroll" data-coreui-target="#list-example" data-coreui-offset="0" class="scrollspy-example" tabindex="0">
<h4 id="list-item-1">Item 1</h4>
<p>...</p>
<h4 id="list-item-2">Item 2</h4>
<p>...</p>
<h4 id="list-item-3">Item 3</h4>
<p>...</p>
<h4 id="list-item-4">Item 4</h4>
<p>...</p>
</div>
Usage
Via data attributes
To easily add scrollspy behavior to your topbar navigation, add data-coreui-spy="scroll"
to the element you want to spy on (most typically this would be the <body>
). Then add the data-coreui-target
attribute with the ID or class of the parent element of any Bootstrap .nav
component.
body {
position: relative;
}
<body data-coreui-spy="scroll" data-coreui-target="#navbar-example">
...
<div id="navbar-example">
<ul class="nav nav-tabs" role="tablist">
...
</ul>
</div>
...
</body>
Via JavaScript
After adding position: relative;
in your CSS, call the scrollspy via JavaScript:
const scrollSpy = new coreui.ScrollSpy(document.body, {
target: '#navbar-example'
})
Options
As options can be passed via data attributes or JavaScript, you can append an option name to data-coreui-
, as in data-coreui-animation="{value}"
. Make sure to change the case type of the option name from “camelCase” to “kebab-case” when passing the options via data attributes. For example, use data-coreui-custom-class="beautifier"
instead of data-coreui-customClass="beautifier"
.
As of CoreUI 4.2.0, all components support an experimental reserved data attribute data-coreui-config
that can house simple component configuration as a JSON string. When an element has data-coreui-config='{"delay":0, "title":123}'
and data-coreui-title="456"
attributes, the final title
value will be 456
and the separate data attributes will override values given on data-coreui-config
. In addition, existing data attributes are able to house JSON values like data-coreui-delay='{"show":0,"hide":150}'
.
Name | Type | Default | Description |
---|---|---|---|
rootMargin |
string | 0px 0px -25% |
Intersection Observer rootMargin valid units, when calculating scroll position. |
smoothScroll |
boolean | false |
Enables smooth scrolling when a user clicks on a link that refers to ScrollSpy observables. |
target |
string, DOM element | null |
Specifies element to apply Scrollspy plugin. |
Deprecated Options
Up until v5.1.3 we were using offset
& method
options, which are now deprecated and replaced by rootMargin
.
To keep backwards compatibility, we will continue to parse a given offset
to rootMargin
, but this feature will be removed in v6.
Methods
Method | Description |
---|---|
dispose |
Destroys an element’s scrollspy. (Removes stored data on the DOM element) |
getInstance |
Static method to get the scrollspy instance associated with a DOM element |
getOrCreateInstance |
Static method to get the scrollspy instance associated with a DOM element, or to create a new one in case it wasn’t initialized. |
refresh |
When adding or removing elements in the DOM, you’ll need to call the refresh method. |
Here’s an example using the refresh method:
const dataSpyList = document.querySelectorAll('[data-coreui-spy="scroll"]')
dataSpyList.forEach(dataSpyEl => {
coreui.ScrollSpy.getInstance(dataSpyEl).refresh()
})
Events
Event | Description |
---|---|
activate.coreui.scrollspy |
This event fires on the scroll element whenever an anchor is activated by the scrollspy. |
const firstScrollSpyEl = document.querySelector('[data-coreui-spy="scroll"]')
firstScrollSpyEl.addEventListener('activate.coreui.scrollspy', () => {
// do something...
})