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alarms.onAlarm

Fired when any alarm set by the extension goes off.

Syntax

browser.alarms.onAlarm.addListener(listener)
browser.alarms.onAlarm.removeListener(listener)
browser.alarms.onAlarm.hasListener(listener)

Events have three functions:

addListener(listener)
Adds a listener to this event.
removeListener(listener)
Stop listening to this event. The listener argument is the listener to remove.
hasListener(listener)
Check whether listener is registered for this event. Returns true if it is listening, false otherwise.

addListener syntax

Parameters

listener

Function that will be called when this event occurs. The function will be passed the following arguments:

alarm
alarms.Alarm. The alarm that fired. Use Alarm.name to figure out which alarm fired.

Examples

Handle an alarm going off:

function handleAlarm(alarmInfo) {
  console.log("on alarm: " + alarmInfo.name);
}

browser.alarms.onAlarm.addListener(handleAlarm);

Example extensions

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
onAlarm
Yes
79
45
?
Yes
14
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?
48
?
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?

Note: This API is based on Chromium's chrome.alarms API.

Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/alarms/onAlarm