Draft
This page is not complete.
Secure context
This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
The WakeLockSentinel
interface of the Screen Wake Lock API
provides a handle to the underlying platform wake lock and can be manually released and reacquired. An Object
representing the wake lock is returned via the navigator.wakelock.request()
method.
An acquired WakeLockSentinel
can be released manually via the release()
method, or automatically via the platform wake lock. This can happen if the document becomes inactive or looses visibility, if the device is low on power or the user turns on a power save mode. Releasing all WakeLockSentinel
instances of a given wake lock type will cause the underlying platform wake lock to be released.
Properties
This interface provides the following properties.
type
Read only- Returns a
String
representation of the currently acquiredWakeLockSentinel
type.
Return values are:'screen'
: A screen wake lock. Prevents devices from dimming or locking the screen.
Event handlers
Methods
release()
- Releases the
WakeLockSentinel
, returning aPromise
that is resolved once the sentinel has been successfully released.
Examples
In this example we create an asynchronous function which requests a WakeLockSentinel
. Once acquired we listen for the onrelease
event which can be used to give appropriate UI feedback. The sentinel can be acquired or released via appropriate interactions.
// create a reference for the wake lock let wakeLock = null; // create an async function to request a wake lock const requestWakeLock = async () => { try { wakeLock = await navigator.wakeLock.request('screen'); // listen for our release event wakeLock.addEventListener('release', () => { // if wake lock is released alter the UI accordingly }); } catch (err) { // if wake lock request fails - usually system related, such as battery } } wakeLockOnButton.addEventListener('click', () => { requestWakeLock(); }) wakeLockOffButton.addEventListener('click', () => { if (wakeLock !== null) { wakeLock.release() .then(() => { wakeLock = null; }) } })
Specifications
Specification | Status | Comment |
---|---|---|
Screen Wake Lock API The definition of 'WakeLockSentinel' in that specification. |
Unknown | Initial definition. |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
WakeLockSentinel | Chrome Full support 84 | Edge Full support 84 | Firefox No support No | IE No support No | Opera Full support Yes | Safari No support No | WebView Android Full support 84 | Chrome Android Full support 84 | Firefox Android No support No | Opera Android Full support Yes | Safari iOS No support No | Samsung Internet Android Full support Yes |
onrelease | Chrome Full support 84 | Edge Full support 84 | Firefox No support No | IE No support No | Opera Full support Yes | Safari No support No | WebView Android Full support 84 | Chrome Android Full support 84 | Firefox Android No support No | Opera Android Full support Yes | Safari iOS No support No | Samsung Internet Android Full support Yes |
release | Chrome Full support 84 | Edge Full support 84 | Firefox No support No | IE No support No | Opera Full support Yes | Safari No support No | WebView Android Full support 84 | Chrome Android Full support 84 | Firefox Android No support No | Opera Android Full support Yes | Safari iOS No support No | Samsung Internet Android Full support Yes |
type | Chrome Full support 84 | Edge Full support 84 | Firefox No support No | IE No support No | Opera Full support Yes | Safari No support No | WebView Android Full support 84 | Chrome Android Full support 84 | Firefox Android No support No | Opera Android Full support Yes | Safari iOS No support No | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
- No support
- No support