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# BADownloadManagerDelegate

An interface for reacting to asset download events and processing concluded downloads.

```
protocol BADownloadManagerDelegate : NSObjectProtocol
```

## Topics

### Reacting to download events

[`func downloadDidBegin(BADownload)`](/documentation/BackgroundAssets/BADownloadManagerDelegate/downloadDidBegin(_:))

Informs the delegate about a started asset download.

[`func download(BADownload, didReceive: URLAuthenticationChallenge, completionHandler: (URLSession.AuthChallengeDisposition, URLCredential?) -> Void)`](/documentation/BackgroundAssets/BADownloadManagerDelegate/download(_:didReceive:completionHandler:))

Tells the delegate to resolve the specified URL authentication challenge.

[`func download(BADownload, didWriteBytes: Int64, totalBytesWritten: Int64, totalBytesExpectedToWrite: Int64)`](/documentation/BackgroundAssets/BADownloadManagerDelegate/download(_:didWriteBytes:totalBytesWritten:totalBytesExpectedToWrite:))

Informs the delegate about the progress of the specified asset download.

[`func downloadDidPause(BADownload)`](/documentation/BackgroundAssets/BADownloadManagerDelegate/downloadDidPause(_:))

Informs the delegate about a paused asset download.

### Processing concluded downloads

[`func download(BADownload, finishedWithFileURL: URL)`](/documentation/BackgroundAssets/BADownloadManagerDelegate/download(_:finishedWithFileURL:))

Informs the delegate about a finished asset download and provides the on-disk location.

[`func download(BADownload, failedWithError: any Error)`](/documentation/BackgroundAssets/BADownloadManagerDelegate/download(_:failedWithError:))

Informs the delegate about a failed asset download.

## Relationships

### Inherits From

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

---

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