chrome.alarms
- Description
Use the
chrome.alarms
API to schedule code to run periodically or at a specified time in the future. - Permissions
alarms
Summary
- Types
- Methods
- Events
Types
Alarm
Properties
- namestring
Name of this alarm.
- periodInMinutesnumber optional
If not null, the alarm is a repeating alarm and will fire again in periodInMinutes minutes.
- scheduledTimenumber
Time at which this alarm was scheduled to fire, in milliseconds past the epoch (e.g.
Date.now() + n
). For performance reasons, the alarm may have been delayed an arbitrary amount beyond this.
AlarmCreateInfo
Properties
- delayInMinutesnumber optional
Length of time in minutes after which the
onAlarm
event should fire. - periodInMinutesnumber optional
If set, the onAlarm event should fire every periodInMinutes minutes after the initial event specified by when or delayInMinutes. If not set, the alarm will only fire once.
- whennumber optional
Time at which the alarm should fire, in milliseconds past the epoch (e.g.
Date.now() + n
).
Methods
clear
alarms.clear(name: string, callback: function)
Clears the alarm with the given name.
Parameters
- namestring
The name of the alarm to clear. Defaults to the empty string.
- callbackfunction
The callback parameter should be a function that looks like this:
(wasCleared: boolean) => {...}
- wasClearedboolean
clearAll
alarms.clearAll(callback: function)
Clears all alarms.
Parameters
- callbackfunction
The callback parameter should be a function that looks like this:
(wasCleared: boolean) => {...}
- wasClearedboolean
create
alarms.create(name?: string, alarmInfo: AlarmCreateInfo)
Creates an alarm. Near the time(s) specified by alarmInfo, the onAlarm
event is fired. If there is another alarm with the same name (or no name if none is specified), it will be cancelled and replaced by this alarm.
In order to reduce the load on the user's machine, Chrome limits alarms to at most once every 1 minute but may delay them an arbitrary amount more. That is, setting delayInMinutes
or periodInMinutes
to less than 1
will not be honored and will cause a warning. when
can be set to less than 1 minute after "now" without warning but won't actually cause the alarm to fire for at least 1 minute.
To help you debug your app or extension, when you've loaded it unpacked, there's no limit to how often the alarm can fire.
Parameters
- namestring optional
Optional name to identify this alarm. Defaults to the empty string.
- alarmInfo
Describes when the alarm should fire. The initial time must be specified by either when or delayInMinutes (but not both). If periodInMinutes is set, the alarm will repeat every periodInMinutes minutes after the initial event. If neither when or delayInMinutes is set for a repeating alarm, periodInMinutes is used as the default for delayInMinutes.
get
alarms.get(name?: string, callback: function)
Retrieves details about the specified alarm.
getAll
alarms.getAll(callback: function)
Gets an array of all the alarms.