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For a Flutter project I need to call a method channel in order to run platform specific code for iOS devices.I would like to provide the VNDocumentCameraViewController of the VisionKit framework and in order to send the image path back to Flutter, I need to register a completion handler that runs after the VNDocumentCameraViewController is dismissed.Therefore, I have a FlutterChannelManager that initializes the custom class DocumentCameraHandler which conforms to VNDocumentCameraViewController and VNDocumentCameraViewControllerDelegate and provides a handler for the result.The VNDocumentCameraViewController is presented as expected and I can scan documents and everything but when the view controller is dismissed, the VNDocumentCameraViewControllerDelegate methods are somehow not called and my app throws the following error on the main thread:Thread 1: EXC_BAD_ACCESS (code=1, address=0x1f9400aa8)These are the relevant classes in my project:@available(iOS 13.0, *)class FlutterChannelManager: NSObject { unowned let flutterViewController: UIViewController init(flutterViewController: UIViewController) { self.flutterViewController = flutterViewController } func setup(){ let documentCamera = buildDocumentCamera() self.flutterViewController.present(documentCamera, animated: true) } func buildDocumentCamera() -> UIViewController { return DocumentCameraHandler { (image) in self.flutterViewController.dismiss(animated: true, completion: nil) if let image = image { print("SUCCESS") } else { print("ERROR") } } }}@available(iOS 13.0, *)class DocumentCameraHandler: VNDocumentCameraViewController, UINavigationControllerDelegate, VNDocumentCameraViewControllerDelegate { var handler: ((_ image: UIImage?) -> Void)? convenience init(handler: @escaping (_ image: UIImage?) -> Void) { self.init() self.delegate = self self.handler = handler } func documentCameraViewController(_ controller: VNDocumentCameraViewController, didFinishWith scan: VNDocumentCameraScan) { handler?(scan.imageOfPage(at: 0)) } func documentCameraViewControllerDidCancel(_ controller: VNDocumentCameraViewController) { handler?(nil) } func documentCameraViewController(_ controller: VNDocumentCameraViewController, didFailWithError error: Error) { handler?(nil) }}