SwiftUI确定初始视图

我试图弄清楚我在SwiftUI生命周期中制作的应用程序的导航。根据启动时确定的设置，用户可以从三个视图之一开始。如果用户从推送通知中打开应用程序，则他们应该看到视频视图（WrappedVideoViewController）。否则，如果他们已经登录，则应该看到“主页”视图，否则，应该看到“登录”视图。我使用ContentView作为父项：

import SwiftUI

struct ContentView: View {
    @EnvironmentObject var notifService: NotificationService
    @EnvironmentObject var authState: AuthenticationState
    
    @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
        
    @ObservedObject var viewRouter: ViewRouter
    
    init() {
        self.viewRouter = ViewRouter.shared
    }
    
    var body: some View {
        
        print("in ContentView body")
        
        switch viewRouter.currentScreen {
        case .home:
            print("home")
            return AnyView(Home(innerGradientColor: Color.homeActiveInner, outerGradientColor: Color.homeActiveOuter))
        case .login:
            print("login")
            return
                AnyView(Login()
                .environmentObject(AuthenticationState.shared))
        case .video:
            print("video")
            return AnyView(WrappedVideoViewController())

        }
            
    }

}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
            .environmentObject(AuthenticationState.shared)
            .environmentObject(NotificationService())
    }
}

我的ViewRouter类是一个ObservableObject，用于控制显示哪个屏幕。目前，我有这个：

//
//  NavigationState.swift
//  BumpCall-SwiftUI
//
//  Created by Ben on 1/22/21.
//

import Foundation
import SwiftUI

enum Screen {
    case home
    case video
    case login
}

class ViewRouter: ObservableObject {
    
    var authState: AuthenticationState
    var notifService: NotificationService
    
    static var shared = ViewRouter(authState: AuthenticationState.shared, notifService: NotificationService.shared)
    
    init(authState: AuthenticationState, notifService: NotificationService) {
        self.authState = authState
        self.notifService = notifService
        
        if notifService.dumbData != nil {
            currentScreen = .video
        } else if (notifService.dumbData == nil && authState.isLoggedIn()) {
            currentScreen = .home
        } else {
            currentScreen = .login
        }
        
    }
    
    @Published var currentScreen: Screen
    
}

这很棘手，因为ViewRouter依赖于其他两个ObservableObjects，我正在尝试使用init（）处理它。看来AuthenticationState类工作正常，因为打开应用程序后，如果您登录了，它确实会将您发送到主屏幕。但是，从通知中打开也会将我发送到主屏幕。NotificationService在didReceive响应中更改ViewRouter单例：方法：

class NotificationService: NSObject, ObservableObject {
    @Published var dumbData: UNNotificationResponse?
    
    static var shared = NotificationService()
    
    override init() {
        super.init()
        UNUserNotificationCenter.current().delegate = self
    }
}

extension NotificationService: UNUserNotificationCenterDelegate  {
    func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        print("presenting notification")
    }

    func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
        ViewRouter.shared.notifService.dumbData = response
        print("Notification service didReceive response")
        completionHandler()
    }

    func userNotificationCenter(_ center: UNUserNotificationCenter, openSettingsFor notification: UNNotification?) { }
    
}

但是单例不得更新，以使ContentView注意到。这太令人费解了，已经使我困惑了好几天，任何帮助将不胜感激。