如何使用 FCM (iOS) 获取远程通知的内容？

Posted 2023-02-24

【中文标题】如何使用 FCM (iOS) 获取远程通知的内容？

【英文标题】：How to get the content of remote notification using FCM (iOS)?

【发布时间】：2017-01-14 18:29:54

【问题描述】：

我正在使用 FCM 向使用此方法的设备发送推送通知

 func push(message: String, toUser: String) 
    var token: String?
    for person in self.users 
        if toUser == person.username && person.firebaseToken != nil 
            token = person.firebaseToken
        
    
    if token != nil 
        var request = URLRequest(url: URL(string: "https://fcm.googleapis.com/fcm/send")!)
        request.httpMethod = "POST"
        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
        request.setValue("key=[your FCM Server Key]", forHTTPHeaderField: "Authorization")
        let json = [
            "to" : token!,
            "priority" : "high",
            "notification" : [
                "body" : message
            ]
        ] as [String : Any]
        do 
            let jsonData = try JSONSerialization.data(withJSONObject: json, options: .prettyPrinted)
            request.httpBody = jsonData
            let task = URLSession.shared.dataTask(with: request)  data, response, error in
                guard let data = data, error == nil else 
                    print("Error=\(error)")
                    return
                

                if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 
                    // check for http errors
                    print("Status Code should be 200, but is \(httpStatus.statusCode)")
                    print("Response = \(response)")
                

                let responseString = String(data: data, encoding: .utf8)
                print("responseString = \(responseString)")
            
            task.resume()
        
        catch 
            print(error)
        
    

但设备只是获取消息而没有对其进行任何操作。 我也在尝试保存它的内容。我怎样才能做到这一点？将其保存到 Firebase 数据库是唯一的选择吗？

谢谢。

【参考方案1】：

您需要通过 AppDelegate 处理通知。您将首先在 didFinishLaunchingWithOptions 中注册通知。由于 firebase 在首次启动消息传递时没有密钥，因此您还需要注册以观察该值：

    // register for remote notifications:
    if #available(ios 10.0, *) 
        let authOptions: UNAuthorizationOptions = [.alert, .badge, .sound]
        UNUserNotificationCenter.current().requestAuthorization(options: authOptions, completionHandler:  (_, _) in )
        UNUserNotificationCenter.current().delegate = self
        FIRMessaging.messaging().remoteMessageDelegate = self
     else 
        let settings: UIUserNotificationSettings = UIUserNotificationSettings(types: [.alert, .badge, .sound], categories: nil)
        application.registerUserNotificationSettings(settings)
    


    application.registerForRemoteNotifications()

    NotificationCenter.default.addObserver(forName: NSNotification.Name.firInstanceIDTokenRefresh, object: nil, queue: nil, using: tokenRefreshNotification(_:))

然后你需要一个连接到 FCM 的方法：

extension AppDelegate 
    func connectToFCM() 
        FIRMessaging.messaging().connect  (error) in
            if error != nil 
                print("unable to connect to FCM \(error)")
             else 
                print("connected to FCM")
            
        
    

以及获得新令牌时的处理方式：

extension AppDelegate 
    func tokenRefreshNotification(_ notification: Notification) 
        if let refreshedToken = FIRInstanceID.instanceID().token() 
            UserDefaults.standard.set(refreshedToken, forKey: "registrationToken")
        

        connectToFCM()
    

最后，您需要实际处理通知。推送通知的实际内容在 iOS 10 及更高版本的“通知”对象中：

@available(iOS 10, *)
extension AppDelegate : UNUserNotificationCenterDelegate 

    // Receive displayed notifications for iOS 10 devices.
    func userNotificationCenter(_ center: UNUserNotificationCenter,
                            willPresent notification: UNNotification,
                            withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) 

        let userInfo = notification.request.content.userInfo

        PushService.handle(userInfo) // do whatever you need with this

    

而要处理其他类型的通知，您可以使用旧方法：

func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable : Any]) 
    //user tapped on notification
    PushService.handle(userInfo) // do what you need with the userInfo dict here, which contains the push notification information

【讨论】：

谢谢！如果设备没有收到通知，您知道通知将保留多长时间吗？如果我发送显示“123”的通知并且另一台设备已关闭，然后我在一周后打开它，应用程序会收到推送吗？或者如果应用程序打开了，它仍然会调用这些函数来保存数据吗？

在设备上收到通知后，它会一直保留在设备上，直到应用程序再次打开。如果应用程序是后台的，它将调用 didReceieveRemoteNotification 或 ios 10 等效项（userNotificationCenter），但如果应用程序已关闭，则推送通知有效负载将包含在应用程序的“选项”中（didFinishLaunchingWithOptions）