我正在努力显示从FCM通知控制台发送到设备的推送通知。我可以看到设备正在接收通知，因为我可以看到发送“ test8”的消息

Connected to FCM.
%@ [AnyHashable("notification"): {
    body = test8;
    e = 1;
},

但是，无论我的应用程序位于前台还是后台都没有关系，但我不会显示通知。

我已在info.plist中添加了“必需的后台模式-
应用程序下载内容以响应推送通知”。我的证书是正确的，并且生成令牌没有问题。我的应用程序正在接收通知，但未显示它们。

import UIKit
import UserNotifications
import Firebase
import FirebaseInstanceID
import FirebaseMessaging

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func application(application: UIApplication,
                     didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {

        // [START register_for_notifications]
        if #available(iOS 10.0, *) {
            let authOptions : UNAuthorizationOptions = [.Alert, .Badge, .Sound]
            UNUserNotificationCenter.currentNotificationCenter().requestAuthorizationWithOptions(
                authOptions,
                completionHandler: {_,_ in })

            // For iOS 10 display notification (sent via APNS)
            UNUserNotificationCenter.currentNotificationCenter().delegate = self
            // For iOS 10 data message (sent via FCM)
            FIRMessaging.messaging().remoteMessageDelegate = self

        } else {
            let settings: UIUserNotificationSettings =
                UIUserNotificationSettings(forTypes: [.Alert, .Badge, .Sound], categories: nil)
            application.registerUserNotificationSettings(settings)
            application.registerForRemoteNotifications()
        }

        application.registerForRemoteNotifications()

        // [END register_for_notifications]

        FIRApp.configure()

        // Add observer for InstanceID token refresh callback.
        NSNotificationCenter.defaultCenter().addObserver(self,
                                                         selector: #selector(self.tokenRefreshNotification),
                                                         name: kFIRInstanceIDTokenRefreshNotification,
                                                         object: nil)

        return true
    }

    // [START receive_message]
    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)
    }
    // [END receive_message]

    // [START refresh_token]
    func tokenRefreshNotification(notification: NSNotification) {
        if let refreshedToken = FIRInstanceID.instanceID().token() {
            print("InstanceID token: \(refreshedToken)")
        }

        // Connect to FCM since connection may have failed when attempted before having a token.
        connectToFcm()
    }
    // [END refresh_token]

    // [START 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.")
            }
        }
    }
    // [END connect_to_fcm]

    func applicationDidBecomeActive(application: UIApplication) {
        connectToFcm()
    }

    // [START disconnect_from_fcm]
    func applicationDidEnterBackground(application: UIApplication) {
        FIRMessaging.messaging().disconnect()
        print("Disconnected from FCM.")
    }
    // [END disconnect_from_fcm]
}

// [START ios_10_message_handling]
@available(iOS 10, *)
extension AppDelegate : UNUserNotificationCenterDelegate {

    // Receive displayed notifications for iOS 10 devices.
    func userNotificationCenter(center: UNUserNotificationCenter,
                                willPresentNotification notification: UNNotification,
                                withCompletionHandler completionHandler: (UNNotificationPresentationOptions) -> Void) {
        let userInfo = notification.request.content.userInfo
        // Print message ID.
        print("Message ID: \(userInfo["gcm.message_id"]!)")
        // Print full message.
        print("%@", userInfo)
    }
}

extension AppDelegate : FIRMessagingDelegate {
    // Receive data message on iOS 10 devices.
    func applicationReceivedRemoteMessage(remoteMessage: FIRMessagingRemoteMessage) {
        print("%@", remoteMessage.appData)
    }
}
// [END ios_10_message_handling]

我一直在尝试自己研究和解决此问题，但遇到了问题。任何帮助或建议，将不胜感激。