AppDelegate与SwiftUI视图之间的通信

import SwiftUI
import Combine

class CommunicationManager: ObservableObject {
    @Published var message: String = ""
    
    func sendMessage(_ message: String) {
        self.message = message
    }
}

import UIKit
import SwiftUI

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?
    var communicationManager = CommunicationManager()

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // 设置环境对象
        let contentView = ContentView().environmentObject(communicationManager)
        
        // 创建UIWindow并设置根视图
        window = UIWindow(frame: UIScreen.main.bounds)
        window?.rootViewController = UIHostingController(rootView: contentView)
        window?.makeKeyAndVisible()
        
        return true
    }
}

import SwiftUI

struct ContentView: View {
    @EnvironmentObject var communicationManager: CommunicationManager
    
    var body: some View {
        VStack {
            Text(communicationManager.message)
            Button(action: {
                self.communicationManager.sendMessage("Hello from SwiftUI!")
            }) {
                Text("Send Message")
            }
        }
    }
}