---
title: HMCharacteristicEvent
framework: homekit
role: symbol
role_heading: Class
path: homekit/hmcharacteristicevent
---

# HMCharacteristicEvent

An event that is evaluated based on the value of a characteristic.

## Declaration

```swift
class HMCharacteristicEvent<TriggerValueType> where TriggerValueType : NSCopying
```

## Topics

### Creating a characteristic event

- [init(characteristic:triggerValue:)](homekit/hmcharacteristicevent/init(characteristic:triggervalue:).md)

### Inspecting the event

- [characteristic](homekit/hmcharacteristicevent/characteristic.md)
- [triggerValue](homekit/hmcharacteristicevent/triggervalue.md)

### Configuring the event

- [updateTriggerValue(_:completionHandler:)](homekit/hmcharacteristicevent/updatetriggervalue(_:completionhandler:).md)

## Relationships

### Inherits From

- [HMEvent](homekit/hmevent.md)

### Inherited By

- [HMMutableCharacteristicEvent](homekit/hmmutablecharacteristicevent.md)

### Conforms To

- [CVarArg](swift/cvararg.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [NSCopying](foundation/nscopying.md)
- [NSMutableCopying](foundation/nsmutablecopying.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)

## See Also

### Characteristics

- [HMMutableCharacteristicEvent](homekit/hmmutablecharacteristicevent.md)