BootstrapJS Scrollspy
JS Scrollspy (scrollspy.js)
The Scrollspy plugin is used to automatically update links in a navigation list based on scroll position.
For a tutorial about Scrollspy, read ourBootstrap Scrollspy Tutorial.
Tip: The Scrollspy plugin is often used together with theAffix plugin.
Via data-* Attributes
Adddata-spy="scroll" to the element that should be used as the scrollable area (often this is the<body> element).
Then add thedata-target attribute with a value of the id or the class name of the navigation bar (.navbar). This is to make sure that the navbar is connected with the scrollable area.
Note that scrollable elements must match the ID of the links inside the navbar's list items (<div> matches<a href="#section1">).
The optionaldata-offset attribute specifies the number of pixels to offset from top when calculating the position of scroll. This is useful when you feel that the links inside the navbar changes the active state too soon or too early when jumping to the scrollable elements. Default is 10 pixels.
Requires relative positioning:The element with data-spy="scroll" requires the CSSposition property, with a value of "relative" to work properly.
Example
<body data-spy="scroll" data-target=".navbar" data-offset="50">
<!-- The navbar - The <a> elements are used to jump to a section in the scrollable area -->
<nav class="navbar navbar-inverse navbar-fixed-top">
...
<ul>
<li><a href="#section1">Section 1</a></li>
...
</nav>
<!-- Section 1 -->
<div>
<h1>Section 1</h1>
<p>Try to scroll this page and look at the navigation bar while scrolling!</p>
</div>
...
</body>
Via JavaScript
Enable manually with:
Scrollspy Options
Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-, as in data-offset="".
| Name | Type | Default | Description | Try it |
|---|---|---|---|---|
| offset | number | 10 | Specifies the number of pixels to offset from top when calculating the position of scroll | Try it |
Scrollspy Methods
The following table lists all available scrollspy methods.
| Method | Description | Try it |
|---|---|---|
| .scrollspy("refresh") | When adding and removing elements from the scrollspy, this method can be used to refresh the document | Try it |
Scrollspy Events
The following table lists all available scrollspy events.
| Event | Description | Try it |
|---|---|---|
| activate.bs.scrollspy | Occurs when a new item becomes activated by the scrollspy | Try it |
More Examples
Scrollspy with animated scroll
How to add a smooth page scroll to an anchor on the same page:
Smooth scrolling
$('body').scrollspy({target: ".navbar", offset: 50});
// Add smooth scrolling on all links inside the navbar
$("#myNavbar a").on('click', function(event) {
// Make sure this.hash has a value before overriding default behavior
if (this.hash !== "") {
// Prevent default anchor click behavior
event.preventDefault();
// Store hash
var hash = this.hash;
// Using jQuery's animate() method to add smooth page scroll
// The optional number (800) specifies the number of milliseconds it takes to scroll to the specified area
$('html, body').animate({
scrollTop: $(hash).offset().top
}, 800, function(){
// Add hash (#) to URL when done scrolling (default click behavior)
window.location.hash = hash;
});
} // End if
});
Scrollspy & Affix
Using theAffix plugin together with the Scrollspy plugin:
Horizontal Menu (Navbar)
<nav class="navbar navbar-inverse" data-spy="affix" data-offset-top="197">
...
</nav>
</body>
Vertical Menu (Sidenav)
<nav class="col-sm-3" id="myScrollspy">
<ul class="nav nav-pills nav-stacked" data-spy="affix" data-offset-top="205">
...
</nav>
</body>

