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 toggles the .active class on anchor (<a>) elements when the element with the id referenced by the anchor’s href is scrolled into view. Scrollspy is best used in conjunction with a Bootstrap nav component or list group, but it will also work with any anchor elements in the current page. Here’s how it works.
-
To start, scrollspy requires two things: a navigation, list group, or a simple set of links, plus a scrollable container. The scrollable container can be the
<body>or a custom element with a setheightandoverflow-y: scroll. -
On the scrollable container, add
data-bs-spy="scroll"anddata-bs-target="#navId"wherenavIdis the uniqueidof the associated navigation. Be sure to also include atabindex="0"to ensure keyboard access. -
As you scroll the “spied” container, an
.activeclass is added and removed from anchor links within the associated navigation. Links must have resolvableidtargets, otherwise they’re ignored. For example, a<a href="#home">home</a>must correspond to something in the DOM like<div id="home"></div> -
Target elements that aren’t visible will be ignored and their corresponding nav items will never receive an
.activeclass.
Checkout the examples below to see it in action.
Examples
Navbar
Scroll the area below the navbar and watch the active class change. Open the dropdown menu and watch the dropdown items 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 bg-light 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-bs-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-bs-spy="scroll" data-bs-target="#navbar-example2" data-bs-root-margin="0px 0px -40%" data-bs-smooth-scroll="true" 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>
Nested nav
Scrollspy also works with nested .navs. 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.
Keep in mind that the JavaScript plugin tries to pick the right element among all that may be visible. Multiple visible scrollspy targets at the same time may cause some issues.
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.
Keep in mind that the JavaScript plugin tries to pick the right element among all that may be visible. Multiple visible scrollspy targets at the same time may cause some issues.
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.
Keep in mind that the JavaScript plugin tries to pick the right element among all that may be visible. Multiple visible scrollspy targets at the same time may cause some issues.
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.
Keep in mind that the JavaScript plugin tries to pick the right element among all that may be visible. Multiple visible scrollspy targets at the same time may cause some issues.
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.
Keep in mind that the JavaScript plugin tries to pick the right element among all that may be visible. Multiple visible scrollspy targets at the same time may cause some issues.
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.
Keep in mind that the JavaScript plugin tries to pick the right element among all that may be visible. Multiple visible scrollspy targets at the same time may cause some issues.
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.
Keep in mind that the JavaScript plugin tries to pick the right element among all that may be visible. Multiple visible scrollspy targets at the same time may cause some issues.
<nav id="navbar-example3" class="navbar bg-light 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-bs-spy="scroll" data-bs-target="#navbar-example3" data-bs-smooth-scroll="true" tabindex="0">
<div id="item-1">
<h4>Item 1</h4>
<p>...</p>
</div>
<div id="item-1-1">
<h5>Item 1-1</h5>
<p>...</p>
</div>
<div id="item-1-2">
<h5>Item 1-2</h5>
<p>...</p>
</div>
<div id="item-2">
<h4>Item 2</h4>
<p>...</p>
</div>
<div id="item-3">
<h4>Item 3</h4>
<p>...</p>
</div>
<div id="item-3-1">
<h5>Item 3-1</h5>
<p>...</p>
</div>
<div id="item-3-2">
<h5>Item 3-2</h5>
<p>...</p>
</div>
</div>
List group
Scrollspy also works with .list-groups. 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-bs-spy="scroll" data-bs-target="#list-example" data-bs-smooth-scroll="true" 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>
Simple anchors
Scrollspy is not limited to nav components and list groups, so it will work on any <a> anchor elements in the current document. Scroll the area 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.
Item 5
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="d-flex flex-column">
<a href="#item-1">Item 1</a>
<a href="#item-2">Item 2</a>
<a href="#item-3">Item 3</a>
<a href="#item-4">Item 4</a>
</div>
<div data-bs-spy="scroll" data-bs-target="#list-example" data-bs-offset="0" data-bs-smooth-scroll="true" class="scrollspy-example" tabindex="0">
<h4 id="item-1">Item 1</h4>
<p>...</p>
<h4 id="item-2">Item 2</h4>
<p>...</p>
<h4 id="item-3">Item 3</h4>
<p>...</p>
<h4 id="item-4">Item 4</h4>
<p>...</p>
</div>
Usage
Via data attributes
To easily add scrollspy behavior to your topbar navigation, add data-bs-spy="scroll" to the element you want to spy on (most typically this would be the <body>). Then add the data-bs-target attribute with the id or class name of the parent element of any Bootstrap .nav component.
<body data-bs-spy="scroll" data-bs-target="#navbar-example">
...
<div id="navbar-example">
<ul class="nav nav-tabs" role="tablist">
...
</ul>
</div>
...
</body>
Via JavaScript
const scrollSpy = new bootstrap.ScrollSpy(document.body, {
target: '#navbar-example'
})
Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-bs-, as in data-bs-animation="". 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-bs-custom-class="beautifier" instead of data-bs-customClass="beautifier".
As of Bootstrap 5.2.0, all components support an experimental reserved data attribute data-bs-config that can house simple component configuration as a JSON string. When an element has data-bs-config='{"delay":0, "title":123}' and data-bs-title="456" attributes, the final title value will be 456 and the separate data attributes will override values given on data-bs-config. In addition, existing data attributes are able to house JSON values like data-bs-delay='{"show":0,"hide":150}'.
| Name | Type | Default | Description |
|---|---|---|---|
rootMargin |
string | 0px 0px -40% |
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 | jQuery object | DOM element | 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 |
|---|---|
refresh |
When adding or removing elements in the DOM, you’ll need to call the refresh method. |
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. |
Here’s an example using the refresh method:
const dataSpyList = document.querySelectorAll('[data-bs-spy="scroll"]')
dataSpyList.forEach(dataSpyEl => {
bootstrap.ScrollSpy.getInstance(dataSpyEl).refresh()
})
Events
| Event | Description |
|---|---|
activate.bs.scrollspy |
This event fires on the scroll element whenever an anchor is activated by the scrollspy. |
const firstScrollSpyEl = document.querySelector('[data-bs-spy="scroll"]')
firstScrollSpyEl.addEventListener('activate.bs.scrollspy', () => {
// do something...
})