How can you know that a push notification has been received in iOS (Objective-C)?

Question

Objective-C

How can you know that a push notification has been received in iOS (Objective-C)?
For example, in android there is a method: onMessageReceived from com.google.android.gms.gcm.GcmListenerService.
And in Objective-C - how is it done?

Answer 1

Handling Remote Notifications
https://developer.apple.com/library/content/docume...

Answer 2

If the application is completely unloaded, then nothing. In this case, if a notification arrives with the Alert field filled in, the system will process such notification itself and display it.
If the application is in the device's memory, then this method will work .