在后台模式下未调用ios 10 Firebase推送通知委托方法

Question

I have been struggling with this problem for days and I have looked at every post about this and nothing works.

I am using FCM (Firebase Cloud Messaging). FCM talks directly to the app when in foreground, but it will use APNS when the app is in background.

I am trying to call a method everytime the app got notification by calling the method in the push notification's delegate function

I have these 2 delegate functions: func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void) and func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) which does not get called in background, according to apple documentation.

I also have this function which I believe should get called in the background but it does not. func application(_ application: UIApplication,didReceiveRemoteNotification userInfo: [AnyHashable: Any],fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void)

I have all of these functions in ViewController

In background mode, I get banner notifications, but none of the delegate is called. Is there any way to make any of them work in the background, if not what should I do? In addition I also get this error : <FIRMessaging/WARNING> FIRMessaging receiving notification in invalid state 2 in the log everytime I send a payload while the app is in the background.

Here is the payload that I send using postmate:

{ "priority":"high", "notification":{ "sound": "default", "badge": "1", "title":"mytitle", "body":"mybody", "message":"Hello" }, "content_available":true, "to" : "/topics/myTopic" } I already turned on push notification in capabilities and checked push notification in background modes under capabilities.

I use Xcode 8 and have been testing on iphone 6 iOS 10.0.2

Answer 1

There can only be 1 delegate for a protocol.

In this case, I made APPDelegate and ViewController conform to UIApplicationDelegate. And only delegate functions in APPDelegate got called. That's why the one in ViewController is not called.

The solution would be just put didReceiveRemoteNotification in the AppDelegate.