使用UIHostingController将值从SwiftUI传递到UIViewController

import SwiftUI

struct ContentView: View {
    @State private var message = ""

    var body: some View {
        VStack {
            TextField("Enter Message", text: $message)
                .padding()
            
            Button(action: {
                // 调用传递值的方法
                self.passValueToUIViewController()
            }) {
                Text("Pass Value")
            }
        }
    }
    
    func passValueToUIViewController() {
        // 创建一个 UIHostingController 并设置其 rootView 为当前的 SwiftUI View
        let controller = UIHostingController(rootView: SecondViewController(message: self.message))
        
        // 在当前的 UIViewController 中弹出 UIHostingController
        UIApplication.shared.windows.first?.rootViewController?.present(controller, animated: true, completion: nil)
    }
}

import UIKit

class SecondViewController: UIViewController {
    var message: String
    
    init(message: String) {
        self.message = message
        super.init(nibName: nil, bundle: nil)
    }
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 在 UIViewController 的视图中显示从 SwiftUI 传递过来的值
        let label = UILabel(frame: CGRect(x: 0, y: 0, width: 200, height: 50))
        label.text = message
        label.textAlignment = .center
        label.center = view.center
        view.addSubview(label)
    }
}

import SwiftUI

@main
struct MyApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}