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  "framework" : "CoreMotion",
  "identifier" : "/documentation/CoreMotion/CMWaterSubmersionManagerDelegate/manager(_:didUpdate:)-6qux6",
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# manager(_:didUpdate:)

Tells the delegate when a water submersion event occurs.

```
optional func manager(_ manager: CMWaterSubmersionManager, didUpdate event: CMWaterSubmersionEvent)
```

## Parameters

`manager`

The manager for water submersion data.

`event`

An event indicating that the submersion state has changed.

## Discussion

Implement this method to respond to changes in the device’s submersion state.

```swift
nonisolated func manager(_ manager: CMWaterSubmersionManager, didUpdate event: CMWaterSubmersionEvent) {

    let submerged: Bool?
    switch event.state {
    case .unknown:
        logger.info("*** Received an unknown event ***")
        submerged = nil

    case .notSubmerged:
        logger.info("*** Not Submerged Event ***")
        submerged = false

    case .submerged:
        logger.info("*** Submerged Event ***")
        submerged = true

    @unknown default:
        fatalError("*** unknown event received: \(event.state) ***")
    }

    Task {
        await myAdd(event: event)
        if let submerged {
            await mySet(submerged: submerged)
        }
    }
}
```

---

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