Swift iOS：如何访问AnyHashable数据并加载到视图

Hey there! 既然你已经能从通知的userInfo里解析出title和body这些数据了，接下来把它们展示到视图上其实很 straightforward，我给你分几种常见场景来讲解：

1. UIKit项目（AppDelegate 处理通知） #

如果你是在AppDelegate的userNotificationCenter(_:didReceive:withCompletionHandler:)方法里解析的userInfo，那要把数据传到目标ViewController有几种办法：

• 直接跳转并传值：
  先拿到当前的window根控制器，或者通过导航栈push到目标页面，把解析好的title和body传过去。比如：

  func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
      let userInfo = response.notification.request.content.userInfo
      
      // 你的解析代码
      guard let aps = userInfo[AnyHashable("aps")] as? NSDictionary, 
            let alert = aps["alert"] as? NSDictionary, 
            let body = alert["body"] as? String, 
            let title = alert["title"] as? String else {
          completionHandler()
          return
      }
      
      // 获取当前根控制器，假设是UINavigationController
      guard let navController = UIApplication.shared.windows.first?.rootViewController as? UINavigationController else {
          completionHandler()
          return
      }
      
      // 实例化目标ViewController，比如NotificationDetailVC
      let detailVC = NotificationDetailVC()
      detailVC.notificationTitle = title
      detailVC.notificationBody = body
      
      // 跳转过去
      navController.pushViewController(detailVC, animated: true)
      
      completionHandler()
  }
  

  然后在NotificationDetailVC里，只要在viewDidLoad里把值赋值给对应的UILabel就行：

  class NotificationDetailVC: UIViewController {
      var notificationTitle: String?
      var notificationBody: String?
      
      @IBOutlet weak var titleLabel: UILabel!
      @IBOutlet weak var bodyLabel: UILabel!
      
      override func viewDidLoad() {
          super.viewDidLoad()
          titleLabel.text = notificationTitle
          bodyLabel.text = notificationBody
      }
  }
  

• 用通知中心传值：
  如果不想直接依赖导航栈，也可以用NotificationCenter发送通知，让目标ViewController监听：
  在解析完数据后发送：

  let notificationData = ["title": title, "body": body]
  NotificationCenter.default.post(name: NSNotification.Name("NotificationReceived"), object: nil, userInfo: notificationData)
  

  然后在目标VC的viewDidLoad里监听：

  override func viewDidLoad() {
      super.viewDidLoad()
      NotificationCenter.default.addObserver(self, selector: #selector(handleNotification(_:)), name: NSNotification.Name("NotificationReceived"), object: nil)
  }
  
  @objc func handleNotification(_ notification: Notification) {
      guard let data = notification.userInfo as? [String: String],
            let title = data["title"],
            let body = data["body"] else { return }
      titleLabel.text = title
      bodyLabel.text = body
  }
  
  // 记得deinit里移除监听
  deinit {
      NotificationCenter.default.removeObserver(self)
  }
  

2. UIKit项目（SceneDelegate 处理通知） #

如果你的项目是用SceneDelegate的（iOS 13+），那处理逻辑类似，只是获取根控制器的方式变了：

func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
    let userInfo = response.notification.request.content.userInfo
    // 解析数据...
    
    // 获取当前scene的根控制器
    guard let scene = UIApplication.shared.connectedScenes.first as? UIWindowScene,
          let window = scene.windows.first,
          let navController = window.rootViewController as? UINavigationController else {
        completionHandler()
        return
    }
    
    // 后续跳转传值和上面一样
    let detailVC = NotificationDetailVC()
    detailVC.notificationTitle = title
    detailVC.notificationBody = body
    navController.pushViewController(detailVC, animated: true)
    
    completionHandler()
}

3. SwiftUI项目 #

如果是SwiftUI项目，你可以用@Published属性结合ObservableObject来传递数据：
首先，创建一个全局的通知管理器：

class NotificationManager: ObservableObject {
    static let shared = NotificationManager()
    @Published var receivedNotification: (title: String, body: String)?
}

然后在通知处理的地方（比如App.swift里的相关回调或者UNUserNotificationCenterDelegate方法）：

func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) {
    let userInfo = response.notification.request.content.userInfo
    // 解析数据...
    
    NotificationManager.shared.receivedNotification = (title: title, body: body)
    completionHandler()
}

最后在你的SwiftUI视图里监听这个@Published属性：

struct NotificationView: View {
    @StateObject private var notificationManager = NotificationManager.shared
    
    var body: some View {
        VStack {
            if let notification = notificationManager.receivedNotification {
                Text(notification.title)
                    .font(.title)
                Text(notification.body)
                    .font(.body)
                    .padding()
            } else {
                Text("No notification received")
            }
        }
    }
}

关键注意事项 #

• 确保在更新UI的时候是在主队列操作，虽然上面的方法大多已经在主队列，但如果你的解析是异步执行的，记得用DispatchQueue.main.async包裹UI更新代码：

  DispatchQueue.main.async {
      self.titleLabel.text = title
      self.bodyLabel.text = body
  }
  

• 如果App在后台被唤醒，要确保视图已经加载完成再赋值，不然可能会出现UI控件为nil的情况，用通知中心或者ObservableObject的方式会更稳妥。

内容的提问来源于stack exchange，提问作者user9606220