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# MIDINotification

A message that describes a system state change.

```
struct MIDINotification
```

## Topics

### Inspecting the Notification

[`MIDINotificationMessageID`](/documentation/CoreMIDI/MIDINotificationMessageID)

The types of state changes the system supports.

[`messageID`](/documentation/CoreMIDI/MIDINotification/messageID)

An identifier that describes the type of state change.

[`messageSize`](/documentation/CoreMIDI/MIDINotification/messageSize)

The size of the message including its ID.

### Initializers

[`init()`](/documentation/CoreMIDI/MIDINotification/init())

[`init(messageID:messageSize:)`](/documentation/CoreMIDI/MIDINotification/init(messageID:messageSize:))


---

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