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# HMTimerTrigger

A trigger to activate an action set based on a periodic timer.

```
class HMTimerTrigger
```

## Overview

When a timer trigger is enabled using [`enable(_:completionHandler:)`](/documentation/HomeKit/HMTrigger/enable(_:completionHandler:)), the system checks to verify that the timer trigger’s fire date, time zone, and recurrence rules yield a next fire date that is in the future.

## Topics

### Creating a timer trigger

[`-  initWithName:fireDate:recurrence:`](/documentation/HomeKit/HMTimerTrigger/init(name:fireDate:recurrence:))

### Choosing the fire date

[`fireDate`](/documentation/HomeKit/HMTimerTrigger/fireDate)

The time at which the trigger will next fire.

[`-  updateFireDate:completionHandler:`](/documentation/HomeKit/HMTimerTrigger/updateFireDate(_:completionHandler:))

Updates the next fire date for the trigger.

### Using recurrence

[`recurrence`](/documentation/HomeKit/HMTimerTrigger/recurrence)

The interval on which to repeat firing the trigger.

[`-  updateRecurrence:completionHandler:`](/documentation/HomeKit/HMTimerTrigger/updateRecurrence(_:completionHandler:))

Updates the recurrence interval.

### Deprecated symbols

[`-  initWithName:fireDate:timeZone:recurrence:recurrenceCalendar:`](/documentation/HomeKit/HMTimerTrigger/init(name:fireDate:timeZone:recurrence:recurrenceCalendar:))

Initializes a timer trigger with specified timing information.

[`timeZone`](/documentation/HomeKit/HMTimerTrigger/timeZone)

The timezone in which to evaluate the fire time.

[`-  updateTimeZone:completionHandler:`](/documentation/HomeKit/HMTimerTrigger/updateTimeZone(_:completionHandler:))

Updates the trigger’s time zone.

[`recurrenceCalendar`](/documentation/HomeKit/HMTimerTrigger/recurrenceCalendar)

The calendar in which the recurrence value is evaluated.

## Relationships

### Conforms To

[`Equatable`](/documentation/Swift/Equatable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`Hashable`](/documentation/Swift/Hashable)

[`CVarArg`](/documentation/Swift/CVarArg)

[`Sendable`](/documentation/Swift/Sendable)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

### Inherits From

[`HMTrigger`](/documentation/HomeKit/HMTrigger)

---

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