firebaseMessagingBackgroundHandler method Null safety

Implementation

Future<void> firebaseMessagingBackgroundHandler(RemoteMessage message) async {
  LogManager().addLog("firebaseMessagingBackgroundHandler: ${message.data}", screen: runtimeType.toString());
  math.Random rng = math.Random();
  int tag = rng.nextInt(9999999);
  // LogManager().addLog("receive push message on background: ${message.data}", screen: runtimeType.toString());
  // LogManager().addLog("message.data", screen: runtimeType.toString());
  await Firebase.initializeApp();
  // LogManager().addLog("message.data", screen: runtimeType.toString());
  // LogManager().addLog(message.data.toString(), screen: runtimeType.toString());
  // print("message.data");
  // print(message.data);
  if (message.data != null) {
    Map<String, dynamic> pinpointMessage = message.data;
    pinpointMessage["pinpoint.notification.title"] = message.notification!.title!;
    pinpointMessage["pinpoint.notification.body"] = message.notification!.body!;

    if (flutterLocalNotificationsPlugin == null) {
      flutterLocalNotificationsPlugin = FlutterLocalNotificationsPlugin();
    }
    if (pinpointMessage["pinpoint.notification.imageUrl"] != null && pinpointMessage["pinpoint.notification.imageIconUrl"] != null) {
      log("h2");
      return NotificationService().showBigPictureNotification(pinpointMessage);
    } else if (pinpointMessage["pinpoint.notification.imageUrl"] != null) {
      return NotificationService().showBigPictureNotificationHiddenLargeIcon(pinpointMessage);
    } else {
      flutterLocalNotificationsPlugin.show(
        // pinpointMessage["pinpoint.campaign.campaign_id"].hashCode,
        tag,
        pinpointMessage["pinpoint.notification.title"],
        pinpointMessage["pinpoint.notification.body"],
        NotificationDetails(
          android: AndroidNotificationDetails(
            'high_importance_channel', // id
            'High Importance Notifications', // title
            channelDescription: 'This channel is used for important notifications.',
            // description
            importance: Importance.high,
            icon: null, // android?.smallIcon,
            tag: tag.toString(),
            // other properties...
          ),
        ),
      );
    }
  }
}