final class UserData: BindableObject {
    let didChange = PassthroughSubject<UserData, Never>()

    var image: UIImage? = nil {
        didSet {
            didChange.send(self)
        }
    }
}

struct ContentView : View {
    @EnvironmentObject var userData: UserData

    var body: some View {
        NavigationView {
            VStack {
                if userData.image != nil {
                    Image(uiImage: userData.image!)
                }
                PresentationButton(Text("Import photo"), destination: ImagePicker().environmentObject(userData))
            }
        }
    }
}

struct ImagePickerViewController: UIViewControllerRepresentable {
    @Binding var image: UIImage?

    func updateUIViewController(_ uiViewController: UIImagePickerController, context: UIViewControllerRepresentableContext<ImagePickerViewController>) {
    }

    func makeUIViewController(context: UIViewControllerRepresentableContext<ImagePickerViewController>) -> UIImagePickerController {
        let imagePicker = UIImagePickerController()
        imagePicker.sourceType = UIImagePickerController.SourceType.photoLibrary
        imagePicker.allowsEditing = false
        imagePicker.delegate = context.coordinator
        return imagePicker
    }

    func makeCoordinator() -> Coordinator {
        return Coordinator(self)
    }

    class Coordinator: NSObject, UIImagePickerControllerDelegate, UINavigationControllerDelegate {

        var parent: ImagePickerViewController

        init(_ parent: ImagePickerViewController) {
            self.parent = parent
        }

        func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
            let imagePicked = info[.originalImage] as! UIImage
            parent.image = imagePicked
            picker.dismiss(animated: true, completion: nil)
        }
    }
}

struct ImagePicker : View {
    @EnvironmentObject var userData: UserData

    var body: some View {
        ImagePickerViewController(image: $userData.image)
    }
}