FCM后台通知在iOS中不工作

Question

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

您可以看到，我的JSON中有两个块：一个通知块（在后台接收通知），一个数据块（在前台接收通知）。

我不明白为什么没有收到后台通知。我的怀疑是关于块的顺序（如果我把“数据”块放在“通知”块之前会有问题吗？）。

编辑：有关问题的更多信息。

@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:.
    }


}

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

编辑2：

当应用程序在后台时，不会收到通知，但当我打开应用程序时，会立即收到相同的通知（方法didReceiveRemoteNotification被激发）。

Answer 1

假设您已正确设置了所有内容，那么将消息的priority从normal设置为high应该会使它立即出现。这要归功于iOS捆绑通知和处理通知的方式。您可以在这里了解FCM通知的优先级。请注意，除非有充分的理由，否则不应该在生产中真正使用high，因为它会造成电池损失。

以下是苹果文档中的参考

通知的优先级。指定下列值之一：