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IdleDetector: change event

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

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

Note: This feature is available in Dedicated Web Workers.

The change event of the IdleDetector interface fires when the value of userState or screenState has changed.

Syntax

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

addEventListener("change", (event) => { })

onchange = (event) => { }

Event type

A generic Event.

Example

In the following example, the change callback prints the status of userState and screenState to the console.

idleDetector.addEventListener("change", () => {
  const userState = idleDetector.userState;
  const screenState = idleDetector.screenState;
  console.log(`Idle change: ${userState}, ${screenState}.`);
});

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS
change_event 94 11494–96 No 80 No 94 No 66 No 17.0 94 No

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https://developer.mozilla.org/en-US/docs/Web/API/IdleDetector/change_event