Push notification SwiftUI-当用户打开推送通知时打开特定视图

A有一个用SwiftUI制作的应用程序，解析用于DB。 我是应用程序的一部分，我集成了一些发送通知的云功能（例如：当有人向您发送消息时，您将收到由该云功能触发的推送通知）。 在过去的几天里，我一直在努力寻找当你按下通知打开应用程序时如何打开特定视图。 我已经找到了一些解决方案，但无法让它们发挥作用

这是我目前掌握的代码：

class AppDelegate: NSObject, UIApplicationDelegate, UNUserNotificationCenterDelegate {
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {
        
        //Parse Intialization
        ...
        //notifications
        registerForPushNotifications()
        //Notification Badge
        UIApplication.shared.applicationIconBadgeNumber = 0
        // start notification while app is in Foreground
        UNUserNotificationCenter.current().delegate = self
        return true
    }
    
    // This function will be called right after user tap on the notification
    func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
        print("app opened from PushNotification tap")
        UIApplication.shared.applicationIconBadgeNumber = 0
      completionHandler()
    }
}

@main
struct MyApp: App {
    
    @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
    
    var body: some Scene {
        WindowGroup {
            ContentView(currentTab: Tab.home)
        }
    }
}

应用程序打印“从PushNotification tap打开的应用程序”，但如果我在AppDelegate中放入一个变量，并使用该变量的.onReceive或.onChange侦听ContentView中的更改，则不会出现任何结果

struct ContentView: View {
    @ObservedObject var appState = AppState()
    @State var currentTab : Tab
    @State var noReloadAddItemView = false
    var body: some View {
        TabView(selection: $appState.currentTab) {
            
            NavigationView {
                HomeView(appState: appState, noReloadAddItemView: $noReloadAddItemView)
                
            }
            .tabItem {
                if appState.currentTab == .home {
                    Image(systemName: "house.fill")
                } else {
                    Image(systemName: "house")
                }
                
                Text(LocalizedStringKey("HomeTabMenu"))
                
            }.tag(Tab.home)
            
            NavigationView {
                SearchView(appState: appState, noReloadAddItemView: $noReloadAddItemView)
            }
            .tabItem {
                if appState.currentTab == .search {
                    Image(systemName: "magnifyingglass.circle.fill")
                } else {
                    Image(systemName: "magnifyingglass")
                }
                Text(LocalizedStringKey("SearchTabMenu"))
            }.tag(Tab.search)
            
            NavigationView {
                AddItemView(appState: appState, noReloadAddItemView: $noReloadAddItemView)
            }
            .tabItem {
                if appState.currentTab == .add {
                    Image(systemName: "plus.circle.fill")
                } else {
                    Image(systemName: "plus.circle")
                }
                Text(LocalizedStringKey("SellTabMenu"))
            }.tag(Tab.add)
            
            NavigationView {
                ShoppingCartFavoritesView(appState: appState, noReloadAddItemView: $noReloadAddItemView)
            }
            .tabItem {
                if appState.currentTab == .favorites {
                    Image(systemName: "cart.fill")
                } else {
                    Image(systemName: "cart")
                }
                Text(LocalizedStringKey("CartTabMenu"))
            }.tag(Tab.favorites)
            
            NavigationView {
                ProfileView(appState: appState, noReloadAddItemView: $noReloadAddItemView)
            }
            .tabItem {
                if appState.currentTab == .profile {
                    Image(systemName: "person.fill")
                } else {
                    Image(systemName: "person")
                }
                Text(LocalizedStringKey("ProfileTabMenu"))
            }.tag(Tab.profile)
        }
        .accentColor(Color("ColorMainDark"))
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView(currentTab: Tab.home)
    }
}

class AppState: ObservableObject {
    @Published var currentTab : Tab = .home
}

enum Tab {
    case home, search, add, favorites, profile
}

---

您需要某种共享状态，您可以修改SwiftUI知道如何应对。

可观察对象

非常适合：

class AppState: ObservableObject {
    static let shared = AppState()
    @Published var pageToNavigationTo : String?
}

然后，为了倾听并回应它，您可以在主视图中使用两种不同的方法

选项1——基于ObservedObject值的NavigationLink绑定：

struct ContentView : View {
    @ObservedObject var appState = AppState.shared //<-- note this
    @State var navigate = false
    
    var pushNavigationBinding : Binding<Bool> {
        .init { () -> Bool in
            appState.pageToNavigationTo != nil
        } set: { (newValue) in
            if !newValue { appState.pageToNavigationTo = nil }
        }
    }
    
    var body: some View {
        NavigationView {
            Text("My content")
                .overlay(NavigationLink(destination: Dest(message: appState.pageToNavigationTo ?? ""),
                                        isActive: pushNavigationBinding) {
                    EmptyView()
                })
        }
    }
}

struct Dest : View {
    var message : String
    var body: some View {
        Text("\(message)")
    }
}

我将把特定NavigationView、NavigationLink、TabView等的实现细节留给您，但这应该可以让您开始

最后，一个模拟通知并显示导航视图如何：

class AppDelegate: NSObject, UIApplicationDelegate, UNUserNotificationCenterDelegate {
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {
     
        DispatchQueue.main.asyncAfter(deadline: .now() + 2) {
            print("Dispatch")
            AppState.shared.pageToNavigationTo = "test"
        }
        
        return true
    }
}

class AppState: ObservableObject {
    static let shared = AppState()
    @Published var pageToNavigationTo : String?
}

@main
struct MultiWindowApp: App {
    @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate

    
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

struct ContentView : View {
    @ObservedObject var appState = AppState.shared
    @State var navigate = false
    
    var pushNavigationBinding : Binding<Bool> {
        .init { () -> Bool in
            appState.pageToNavigationTo != nil
        } set: { (newValue) in
            if !newValue { appState.pageToNavigationTo = nil }
        }
    }
    
    var body: some View {
        NavigationView {
            Text("My content")
                .overlay(NavigationLink(destination: Dest(message: appState.pageToNavigationTo ?? ""),
                                        isActive: pushNavigationBinding) {
                    EmptyView()
                })
        }
    }
}


struct Dest : View {
    var message : String
    var body: some View {
        Text("\(message)")
    }
}

类AppDelegate:NSObject、UIApplicationDelegate、UnuseNotificationCenterDelegate{
func应用程序（application:UIApplication，didFinishLaunchingWithOptions launchOptions:[UIApplication.launchOptions:Any]？=nil）->Bool{
DispatchQueue.main.asyncAfter（截止日期：.now（）+2）{
打印（“发送”）
AppState.shared.pageToNavigationTo=“测试”
}
返回真值
}
}
类AppState:ObservableObject{
静态let shared=AppState（）
@已发布变量pageToNavigationTo:字符串？
}
@主要
结构多窗口应用程序：应用程序{
@UIApplicationDelegateAdaptor（AppDelegate.self）变量AppDelegate
var body：一些场景{
窗口组{
ContentView（）
}
}
}
结构ContentView:View{
@ObservedObject var appState=appState.shared
@状态变量导航=false
var pushNavigationBinding:绑定{
.init{（）->Bool-in
appState.pageToNavigationTo！=无
}集合：{（newValue）在
如果！newValue{appState.pageToNavigationTo=nil}
}
}
var body：一些观点{
导航视图{
文本（“我的内容”）
.overlay（导航链接（目的地：Dest（消息：appState.pageToNavigationTo？？），
isActive:pushNavigationBinding）{
EmptyView（）
})
}
}
}
结构目标：视图{
var消息：字符串
var body：一些观点{
文本（“\（消息）”）
}
}

谢谢。它正在工作：）

class AppDelegate: NSObject, UIApplicationDelegate, UNUserNotificationCenterDelegate {
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {
     
        DispatchQueue.main.asyncAfter(deadline: .now() + 2) {
            print("Dispatch")
            AppState.shared.pageToNavigationTo = "test"
        }
        
        return true
    }
}

class AppState: ObservableObject {
    static let shared = AppState()
    @Published var pageToNavigationTo : String?
}

@main
struct MultiWindowApp: App {
    @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate

    
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

struct ContentView : View {
    @ObservedObject var appState = AppState.shared
    @State var navigate = false
    
    var pushNavigationBinding : Binding<Bool> {
        .init { () -> Bool in
            appState.pageToNavigationTo != nil
        } set: { (newValue) in
            if !newValue { appState.pageToNavigationTo = nil }
        }
    }
    
    var body: some View {
        NavigationView {
            Text("My content")
                .overlay(NavigationLink(destination: Dest(message: appState.pageToNavigationTo ?? ""),
                                        isActive: pushNavigationBinding) {
                    EmptyView()
                })
        }
    }
}


struct Dest : View {
    var message : String
    var body: some View {
        Text("\(message)")
    }
}