Window: scrollsnapchange event

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The scrollsnapchange event of the Window interface is fired on the window at the end of a scrolling operation when a new scroll snap target is selected.

This event works in much the same way as the Element interface's scrollsnapchange event, except that the overall HTML document has to be set as the scroll snap container (i.e., scroll-snap-type is set on the <html> element).

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("scrollsnapchange", (event) => {});

onscrollsnapchange = (event) => {};

Event type

A SnapEvent, which inherits from the generic Event type.

Examples

Basic usage

Let's say we have a <main> element containing significant content that causes it to scroll:

html

<main>
  <!-- Significant content -->
</main>

The <main> element can be turned into a scroll container using a combination of CSS properties, for example:

css

main {
  width: 250px;
  height: 450px;
  overflow: scroll;
}

We can then implement scroll snapping behavior on the scrolling content by specifying the scroll-snap-type property on the <html> element:

css

html {
  scroll-snap-type: block mandatory;
}

The following JavaScript snippet would cause the scrollsnapchange event to fire on the HTML document when a child of the <main> element becomes a newly-selected snap target. In the handler function, we set a selected class on the child referenced by the SnapEvent.snapTargetBlock, which could be used to style it to look like it has been selected (for example, with an animation) when the event fires.

window.addEventListener("scrollsnapchange", (event) => {
  event.snapTargetBlock.classList.add("selected");
});

Specifications

Specification
CSS Scroll Snap Module Level 2 # scrollsnapchange

Browser compatibility

BCD tables only load in the browser