将数据从 SwiftUI 视图传递到 UIViewController

Question

I've been testing SwiftUI to see how far I can go with it. Now, I want to find out whether or not I can pass a string from SwiftUI View directly to UIViewController . And I want to display this string with UILabel . UILabel is all I have on my storyoboard.

The following is my view controller ( UIViewController ).

import UIKit
import SwiftUI

class HomeViewController: UIViewController {
    var message = String()

    @IBOutlet weak var messageLabel: UILabel!

    override func viewDidLoad() {
        super.viewDidLoad()
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        messageLabel.text = message
    }
}

struct HomeViewControllerRepresentation: UIViewControllerRepresentable {
    func makeUIViewController(context: UIViewControllerRepresentableContext<HomeViewControllerRepresentation>) -> HomeViewController {
        UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "homeViewController") as! HomeViewController
    }

    func updateUIViewController(_ uiViewController: HomeViewController, context: UIViewControllerRepresentableContext<HomeViewControllerRepresentation>) {

    }
}

My SwiftUI View is the following.

import SwiftUI

struct ContentView: View {
    var body: some View {
        NavigationView {
            VStack {
                NavigationLink(destination: HomeViewControllerRepresentation(message: "GGG")) { // Error
                    Text("Tap me")
                }
            }
            .navigationBarTitle("")
            .navigationBarHidden(true)
        }
    }
}

I hoped that I could just pass a string with HomeViewControllerRepresentation. But it won't work. Is there a simple way of passing data from SwiftUI View to UIViewController ? Thanks.

Answer 1

UIViewControllerRepresentable is not a proxy, but wrapper, so everything should be transferred manually, like

struct HomeViewControllerRepresentation: UIViewControllerRepresentable {
    var message: String

    func makeUIViewController(context: UIViewControllerRepresentableContext<HomeViewControllerRepresentation>) -> HomeViewController {
        let controller = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "homeViewController") as! HomeViewController
        controller.message = self.message
        return controller
    }

    func updateUIViewController(_ uiViewController: HomeViewController, context: UIViewControllerRepresentableContext<HomeViewControllerRepresentation>) {

    }
}