FCM后台通知在iOS中不起作用

Question

我在iOS上的FCM通知有问题。

我收到成功通知时，我的应用程序是在前台（回调didReceiveRemoteNotification中appdelegate被激发），但是当应用程序在后台（我看不出在iOS中的通知栏的任何东西）我没有收到通知。

因此，我认为问题在于FCM发送的消息格式。我的服务器发送到FCM的json格式如下：

{  
   "data":{  
      "title":"mytitle",
      "body":"mybody",
      "url":"myurl"
   },
   "notification":{  
      "title":"mytitle",
      "body":"mybody"
   },
   "to":"/topics/topic"
}

如您所见，我的json中有两个块：一个通知块（用于在后台接收通知）和一个数据块（用于在前台接收通知）。

我不明白为什么没有收到后台通知。我对块的顺序感到怀疑（如果将“数据”块放在“通知”块之前是个问题吗？）。

编辑： 有关该问题的更多信息。

这是我的appdelegate.swift：

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate
{
    var window: UIWindow?


    // Application started
    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject : AnyObject]?) -> Bool
    {
        let pushNotificationSettings: UIUserNotificationSettings = UIUserNotificationSettings(forTypes: [.Alert, .Badge, .Sound], categories: nil)
        application.registerUserNotificationSettings(pushNotificationSettings)
        application.registerForRemoteNotifications()

        FIRApp.configure()

        NSNotificationCenter.defaultCenter().addObserver(self, selector: "tokenRefreshNotification:", name: kFIRInstanceIDTokenRefreshNotification, object: nil)

        return true
    }




    // Handle refresh notification token
    func tokenRefreshNotification(notification: NSNotification) {
        let refreshedToken = FIRInstanceID.instanceID().token()
        print("InstanceID token: \(refreshedToken)")

        // Connect to FCM since connection may have failed when attempted before having a token.
        if (refreshedToken != nil)
        {
            connectToFcm()

            FIRMessaging.messaging().subscribeToTopic("/topics/topic")
        }

    }


    // Connect to FCM
    func connectToFcm() {
        FIRMessaging.messaging().connectWithCompletion { (error) in
            if (error != nil) {
                print("Unable to connect with FCM. \(error)")
            } else {
                print("Connected to FCM.")
            }
        }
    }


    // Handle notification when the application is in foreground
    func application(application: UIApplication, didReceiveRemoteNotification userInfo: [NSObject : AnyObject], fetchCompletionHandler completionHandler: (UIBackgroundFetchResult) -> Void) {
            // If you are receiving a notification message while your app is in the background,
            // this callback will not be fired till the user taps on the notification launching the application.
            // TODO: Handle data of notification

            // Print message ID.
            print("Message ID: \(userInfo["gcm.message_id"])")

            // Print full message.
            print("%@", userInfo)
    }


    // Application will enter in background
    func applicationWillResignActive(application: UIApplication)
    {
        // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
        // Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
    }



    // Application entered in background
    func applicationDidEnterBackground(application: UIApplication)
    {
        FIRMessaging.messaging().disconnect()
        print("Disconnected from FCM.")
    }



    // Application will enter in foreground
    func applicationWillEnterForeground(application: UIApplication)
    {
        // Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
    }



    // Application entered in foreground
    func applicationDidBecomeActive(application: UIApplication)
    {
        connectToFcm()

        application.applicationIconBadgeNumber = 0;
    }



    // Application will terminate
    func applicationWillTerminate(application: UIApplication)
    {
        // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
    }


}

我可以在前台接收消息的唯一方法是禁用方法切换，将info.plist中的FirebaseAppDelegateProxyEnabled设置为NO。

在这种情况下，FCM文档说我必须在appdelegate.swift中实现两个方法：

 - FIRMessaging.messaging().appDidReceiveMessage(userInfo)  in didReceiveRemoteNotification callback
 - FIRInstanceID.instanceID().setAPNSToken(deviceToken, type: FIRInstanceIDAPNSTokenType.Sandbox) in didRegisterForRemoteNotificationsWithDeviceToken callback

但是，如果我实现了这些功能，即使应用程序处于前台，消息也会停止到达。

我知道这很奇怪。

编辑2：

当应用程序在后台运行时，不会收到通知，但是当我打开我的应用程序时，会立即收到相同的通知（触发了didReceiveRemoteNotification方法）。

Answer 1

假设您已正确设置了所有内容，然后将priority消息的设置为从normal到high应该立即显示。这是因为iOS捆绑了通知并处理它们的方式。您可以在此处阅读有关FCM通知的优先级的信息。请注意，high除非有很好的理由，否则您不应该真正在生产中使用它，因为它会消耗电池电量。

这是Apple文档的参考

通知的优先级。指定以下值之一：

10 –立即发送推送消息。具有此优先级的通知必须在目标设备上触发警报，声音或标志。将此优先级用于仅包含内容可用键的推送通知是错误的。

5-在考虑设备功耗的情况下，一次发送推送消息。具有此优先级的通知可能会分组并突发发送。它们受到限制，在某些情况下无法交付。如果省略此标头，则APNs服务器会将优先级设置为10。