DocumentScanner.swift

import SwiftUI
import VisionKit

final class ContentViewModel: NSObject, ObservableObject {
    @Published var errorMessage: String?
    @Published var imageArray: [UIImage] = []
    
    func getDocumentCameraViewController() -> VNDocumentCameraViewController {
        let vc = VNDocumentCameraViewController()
        vc.delegate = self
        return vc
    }
    
    func removeImage(image: UIImage) {
        imageArray.removeAll{$0 == image}
    }
}


extension ContentViewModel: VNDocumentCameraViewControllerDelegate {
    
    func documentCameraViewControllerDidCancel(_ controller: VNDocumentCameraViewController) {
        controller.dismiss(animated: true, completion: nil)
    }
      
    func documentCameraViewController(_ controller: VNDocumentCameraViewController, didFailWithError error: Error) {
        errorMessage = error.localizedDescription
    }
      
    func documentCameraViewController(_ controller: VNDocumentCameraViewController, didFinishWith scan: VNDocumentCameraScan) {
      print("Did Finish With Scan.")
        for i in 0..<scan.pageCount {
            self.imageArray.append(scan.imageOfPage(at:i))
        }
        controller.dismiss(animated: true, completion: nil)
    }
}

struct ContentView: View {
    @ObservedObject var viewModel: ContentViewModel
    var body: some View {
        NavigationView {
        List {
            if let error = viewModel.errorMessage {
                Text(error)
            } else {
                ForEach(viewModel.imageArray, id: \.self) { image in
                    Image(uiImage: image)
                        .resizable()
                        .aspectRatio(contentMode: .fit).contextMenu {
                           Button {
                                let items = [image]
                                let ac = UIActivityViewController(activityItems: items, applicationActivities: nil)
                            UIApplication.shared.windows.filter({$0.isKeyWindow}).first?.rootViewController?.present(ac, animated: true)
                           } label: {
                            Label("Share", systemImage: "square.and.arrow.up")
                           }
                           Divider()
                            Button {
                                viewModel.removeImage(image: image)
                            } label: {
                             Label("Delete", systemImage: "delete.left")
                            }
                            
                        }
                }
            }
         }.navigationTitle("Vinson kit Demo")
        .navigationBarItems(leading: Button(action: {
            let items = viewModel.imageArray
            let ac = UIActivityViewController(activityItems: items, applicationActivities: nil)
        UIApplication.shared.windows.filter({$0.isKeyWindow}).first?.rootViewController?.present(ac, animated: true)
        }, label: {
            Text("Share All Images")
        }).disabled(viewModel.imageArray.count == 0), trailing: Button(action: {
            UIApplication.shared.windows.filter({$0.isKeyWindow}).first?.rootViewController?.present(viewModel.getDocumentCameraViewController(), animated: true, completion: nil)
        }, label: {
            Text("Scan New Doc")
        }))
        
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView(viewModel: ContentViewModel())
    }
}