alarms.onAlarm

Fired when any alarm set by the extension goes off.

Syntax

js
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

The function called when this event occurs. The function is passed this argument:

alarm

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

Examples

Handle an alarm going off:

js
function handleAlarm(alarmInfo) {
  console.log(`on alarm: ${alarmInfo.name}`);
}

browser.alarms.onAlarm.addListener(handleAlarm);

Example extensions

Browser compatibility

BCD tables only load in the browser

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