react-native-push-notification in a foreground/background app snippet (put this inside the implementation of AppDelegate.m)

AppDelegate.m

/ Required to register for notifications
- (void)application:(UIApplication *)application didRegisterUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings
{
    [RCTPushNotificationManager didRegisterUserNotificationSettings:notificationSettings];
}
// Required for the register event.
- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken
{
    [RCTPushNotificationManager didRegisterForRemoteNotificationsWithDeviceToken:deviceToken];
}
// Required for the notification event. You must call the completion handler after handling the remote notification.
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
{
    [RCTPushNotificationManager didReceiveRemoteNotification:userInfo fetchCompletionHandler:completionHandler];
}
// Required for the registrationError event.
- (void)application:(UIApplication *)application didFailToRegisterForRemoteNotificationsWithError:(NSError *)error
{
    [RCTPushNotificationManager didFailToRegisterForRemoteNotificationsWithError:error];
}
// Required for the localNotification event.
- (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification
{
    [RCTPushNotificationManager didReceiveLocalNotification:notification];
}

//Called when a notification is delivered to a foreground app.
-(void)userNotificationCenter:(UNUserNotificationCenter *)center willPresentNotification:(UNNotification *)notification withCompletionHandler:(void (^)(UNNotificationPresentationOptions options))completionHandler
{
    NSLog(@"User Info : %@",notification.request.content.userInfo);
    completionHandler(UNAuthorizationOptionSound | UNAuthorizationOptionAlert | UNAuthorizationOptionBadge);
}