单击推送通知时，正确重定向到选项卡栏导航控制器内的视图控制器

Question

我有一个tabBar。它的每个选项卡的ViewControllers 都嵌入在它们各自的NavigationControllers 中。

层次结构：

Tabbarcontroller --> NavigationController --> VC1 --> VC2 -->...VCn (for tab1)

当我单击推送通知时，我必须重定向到其中一个视图控制器说 VC2。我使用的代码如下。

let navigationController = UINavigationController()
let storyboard = UIStoryboard.init(name: "Main", bundle: Bundle.main)
if let chatViewController = storyboard.instantiateViewController(withIdentifier: "chatViewController") as? ChatViewController {
    navigationController.viewControllers = [chatViewController]
    window?.rootViewController = navigationController
}

通过使用它，我被重定向到相应的ViewController。但是，我无法回到tabBar。那么是否有可能以允许我返回标签栏的方式进行重定向，从而提供与 UI 中相同的层次结构？

编辑：

下图显示了我的布局。

我想完成以下工作：

1. 当用户点击推送通知时，应用程序应被定向到 VC-B。 *如果 VC-B 已经在导航堆栈的顶部，则不应为 VC-B 创建新对象并添加到导航堆栈。

2. 如果应用程序已被终止并且用户点击通知，它应该打开 VC-B。

为了确定应用程序是否已终止，我将标志设置为：

func applicationWillTerminate(_ application: UIApplication) {
    UserDefaults.standard.set(true, forKey: UserDefaultsKey.isTerminated)
}

此标志在 didFinishLaunchingWithOptions 函数结束时设置为 false。

对于重定向，我检查此标志以确定应用程序是否已终止：

func performRedirectionToSuitableViewController(userInfo: [AnyHashable: Any]) {
  
    let isTerminated = UserDefaults.standard.object(forKey: UserDefaultsKey.isTerminated) as! Bool
    
    if isTerminated {
        
        let storyboard = UIStoryboard.init(name: "Main", bundle: Bundle.main)
        
        let tab = storyboard.instantiateViewController(withIdentifier: "tabBar") as! UITabBarController
        
        tab.selectedIndex = 0
        
        let nav = tab.viewControllers![0] as! UINavigationController
        
        let chatViewController = storyboard.instantiateViewController(withIdentifier: "chatViewController") as! ChatViewController
        
        chatViewController.chatThreadId = userInfo["thread_id"] as? String
        
        nav.pushViewController(chatViewController, animated: true)

    } else {

        if let tab = window?.rootViewController?.presentedViewController as? UITabBarController {

            let storyboard = UIStoryboard.init(name: "Main", bundle: Bundle.main)

            let chatViewController = storyboard.instantiateViewController(withIdentifier: "chatViewController") as! ChatViewController
                
            chatViewController.chatThreadId = userInfo["thread_id"] as? String
               
            if let nav = tab.selectedViewController as? UINavigationController {
                   
                nav.pushViewController(chatViewController, animated: true)
            }     
        }
    }
}

使用此代码，我的第一个要求已部分满足。需要确定 viewcontroller 是否位于导航堆栈的顶部。

并且，在应用程序终止的情况下，单击推送通知会打开标签栏，并选择默认选择索引。

我花了几天时间试图解决这个问题。但不能让它工作。

Answer 1

我想你必须这样做：

let tabBar: UITabBarController // get your tab bar
tabBar.selectedIndex = 0 // eg. zero. To be sure that you are on correct tab
if let navigation = tabBar.viewControllers?[tabBar.selectedIndex] as? UINavigationController {
    let storyboard = UIStoryboard.init(name: "Main", bundle: Bundle.main)
    if let chatViewController = storyboard.instantiateViewController(withIdentifier: "chatViewController") as? ChatViewController {
        navigation.pushViewController(chatViewController, animated: true)
    }
 }

Answer 2

嗯，你正在设置当前的window.rootViewController，应该是我说的TabBarViewController。这就是为什么你不能回到TabBar

你应该做的是

let storyboard = UIStoryboard.init(name: "Main", bundle: nil)
if let chatViewController = storyboard.instantiateViewController(withIdentifier: "chatViewController") as? ChatViewController, let tabBar = storyboard.instantiateViewController(withIdentifier: "tabBar") as? UITabBarController {
    let navigationController = UINavigationController(rootViewController: chatViewController)
    navigationController.viewControllers = [chatViewController]
    tabBar.viewControllers = [navigationController]
    window?.rootViewController = tabBar
}

Answer 3

从标签栏控制器获取当前导航控制器。你可以使用这个功能

func getVisibleViewController(_ rootViewController: UIViewController?) -> UIViewController? {
        
        var rootVC = rootViewController
        if rootVC == nil {
            rootVC = UIApplication.shared.keyWindow?.rootViewController
        }
        
        if rootVC?.presentedViewController == nil {
            return rootVC
        }
        
        if let presented = rootVC?.presentedViewController {
            if presented.isKind(of: UINavigationController.self) {
                let navigationController = presented as! UINavigationController
                return navigationController.viewControllers.last!
            }
            
            if presented.isKind(of: UITabBarController.self) {
                let tabBarController = presented as! UITabBarController
                return tabBarController.selectedViewController!
            }
            
            //UIAlertController
            if presented.isKind(of: UIAlertController.self) {
                let alertController = presented as! UIAlertController
                return alertController.presentingViewController
            }
            return getVisibleViewController(presented)
        }
        return nil
    }

使用该功能，您可以像下面那样导航您的视图控制器。

let mainStoryboardIpad : UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
                let yourView = mainStoryboardIpad.instantiateViewController(withIdentifier: "yourView") as! NewnoteViewController

                let navi = self.getVisibleViewController(self.window!.rootViewController) as! UINavigationController
               
                navi.pushViewController(yourView, animated: true)

Answer 4

您可以在 RootViewController 中创建一个方法，在收到推送通知后将用户重定向到特定视图。这是我在之前的项目中所做的。

class RootViewController: UIViewController {
    private var currentView: UIViewController
    
    init() {
        self.currentView = ViewController()
        super.init(nibName: nil, bundle: nil)
    }
    
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        addChildViewController(currentView)               // 1
        currentView.view.frame = view.bounds              // 2
        view.addSubview(currentView.view)                 // 3
        currentView.didMove(toParentViewController: self) // 4
    }
    
    func showDetailsScreen() {
        if let updateDetailView = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "UpdateDetailsNotif") as? UpdateDetailsViewController{
            
            let navController = UINavigationController(rootViewController: updateDetailView)

            addChildViewController(navController)
            navController.view.frame = view.bounds
            view.addSubview(navController.view)
            navController.didMove(toParentViewController: self)
            currentView.willMove(toParentViewController: nil)
            currentView.view.removeFromSuperview()
            currentView.removeFromParentViewController()
            currentView = navController
        }
        
    }
   
}

然后您可以像这样在 AppDelegate 上调用该方法：

  func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
        let application = UIApplication.shared
  
        AppDelegate.shared.rootViewController.showDetailsScreen()
       
        completionHandler()
    
    }
}