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# itemThumbnailData(for:)

Asks the delegate for the thumbnail image data to display on the invitation.

```
optional func itemThumbnailData(for csc: UICloudSharingController) -> Data?
```

## Discussion

Implement this method to return image data representing the shared recording. Returning `nil` tells the [`UICloudSharingController`](/documentation/UIKit/UICloudSharingController) instance to display the generic image. Not implementing this method is the same as returning `nil`.

[`itemThumbnailData(for:)`](/documentation/UIKit/UICloudSharingControllerDelegate/itemThumbnailData(for:)) is called only when creating a new share. For an existing share, the thumbnail image is retrieved from the share using the <doc://com.apple.documentation/documentation/CloudKit/CKShareThumbnailImageDataKey-1rxdx> key.

The following code shows an example of retrieving the image data from a data set stored in an asset catalog found in the main bundle.

```swift
- (nullable NSData *)itemThumbnailDataForCloudSharingController:(UICloudSharingController *)csc
{  
  NSDataAsset *icon = [[NSDataAsset alloc] initWithName:@"thumbnail"];
  return [icon data];
}
```

---

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