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# dataScanner(_:becameUnavailableWithError:)

Responds when the data scanner becomes unavailable and stops scanning.

```
@MainActor func dataScanner(_ dataScanner: DataScannerViewController, becameUnavailableWithError error: DataScannerViewController.ScanningUnavailable)
```

## Parameters

`dataScanner`

The data scanner that’s not available.

`error`

Describes an error if it occurs.

---

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