Web/API/Animation/replaceState

This is an experimental technologyCheck the Browser compatibility table carefully before using this in production.

The read-only Animation.replaceState property of the Web Animations API returns the replace state of the animation. This will be active if the animation has been removed, or persisted if Animation.persist() has been invoked on it.

Syntax

let myReplaceState = Animation.replaceState;

Value

A string that represents the replace state of the anmation. The value can be one of:

active: The initial value of the animation's replace state; when the animation has been removed by the browser's Automatically removing filling animations behavior.
persisted: The animation has been explicitly persisted by invoking Animation.persist() on it.
removed: The animation has been explicitly removed.

Examples

In our simple [[../../../../../../../mdn.github.io/dom-examples/web-animations-api/replace-indefinite-animations|replace indefinite animations demo]], you can see the following code:

const divElem = document.querySelector('div');

document.body.addEventListener('mousemove', evt => {
  let anim = divElem.animate(
    { transform: `translate(${ evt.clientX}px, ${evt.clientY}px)` },
    { duration: 500, fill: 'forwards' }
  );

  anim.commitStyles();

  //anim.persist()

  anim.onremove = function() {
    console.log('Animation removed');
  }

  console.log(anim.replaceState);
});

Here we have a <div> element, and an event listener that fires the event handler code whenever the mouse moves. The event handler sets up an animation that animates the <div> element to the position of the mouse pointer. This could result in a huge animations list, which could create a memory leak. For this reason, modern browsers automatically remove overriding forward filling animations.

You can see the replaceState of the animation being logged at the end of the handler. This will be active for each animation by default, or persisted if the persist() call is uncommented.

Specifications

Specification	Status	Comment
Web AnimationsThe definition of 'Animation.replaceState' in that specification.	Working Draft

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`replaceState` Experimental'	Chrome No support No Notes' No support No Notes' Notes' Currently Chrome Canary only	Edge No support No	Firefox Full support 75	IE No support No	Opera No support No	Safari Full support 13.1	WebView Android No support No	Chrome Android No support No Notes' No support No Notes' Notes' Currently Chrome Canary only	Firefox Android No support No	Opera Android No support No	Safari iOS Full support 13.4	Samsung Internet Android No support No

Legend

Full support: Full support
No support: No support
Experimental. Expect behavior to change in the future.': Experimental. Expect behavior to change in the future.
See implementation notes.': See implementation notes.