The claim()
method of the Clients
interface allows an active service worker to set itself as the controller
for all clients within its scope
. This triggers a "controllerchange
" event on navigator.serviceWorker
in any clients that become controlled by this service worker.
When a service worker is initially registered, pages won't use it until they next load. The claim()
method causes those pages to be controlled immediately. Be aware that this results in your service worker controlling pages that loaded regularly over the network, or possibly via a different service worker.
Syntax
await clients.claim();
Parameters
None.
Return value
A Promise
that resolves to undefined
.
Example
The following example uses claim()
inside service worker's "activate
" event listener so that clients loaded in the same scope do not need to be reloaded before their fetches will go through this service worker.
self.addEventListener('activate', event => { event.waitUntil(clients.claim()); });
Specifications
Specification | Status | Comment |
---|---|---|
Service Workers The definition of 'claim()' in that specification. |
Working Draft | Initial definition. |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
claim | Chrome Full support 42 | Edge Full support ≤79 | Firefox
Full support
44
| IE No support No | Opera Full support 29 | Safari No support No | WebView Android Full support 42 | Chrome Android Full support 42 | Firefox Android Full support 44 | Opera Android Full support 29 | Safari iOS No support No | Samsung Internet Android Full support 4.0 |
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.
See also
- Using Service Workers
- The service worker lifecycle
- Is ServiceWorker ready?
Promises
self.skipWaiting()
- skip the service worker's waiting phase