This feature is not Baseline because it does not work in some of the most widely-used browsers.
Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
A close event is fired at a CloseWatcher object when a close request was received and only fired if the cancel event that preceded the close one was not canceled.
The close event handler is where the code to close the UI component should be called: this ensures that the component will be closed properly either from the platform-specific close signal or from a call to CloseWatcher.requestClose().
Use the event name in methods like addEventListener(), or set an event handler property.
addEventListener("close", (event) => { })
onclose = (event) => { }
An Event.
close eventUse the close to listen for close requests.
watcher.addEventListener("close", () => {
// Close your UI component
sidebar.hide();
});
| Specification |
|---|
| HTML> # handler-closewatcher-onclose> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
close_event |
126 | 126 | preview | 112 | No | 126 | No | 83 | No | 28.0 | 126 | No |
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https://developer.mozilla.org/en-US/docs/Web/API/CloseWatcher/close_event