file.dart

Future<void> openOffersPage(RemoteMessage? message) async {
  if (message != null) {
    if (message.data['type'] == 'offers') {
      Navigator.push(
        key.currentContext!,
        MaterialPageRoute(
          builder: (_) => HotOffers(),
        ),
      );
    }
  }
  await messaging.getInitialMessage().then((msg) {
    if (msg!.data['type'] == 'offers') {
      Navigator.push(
        key.currentContext!,
        MaterialPageRoute(
          builder: (_) => HotOffers(),
        ),
      );
    }
  });
}

Future<void> _firebaseMessagingBackgroundHandler(RemoteMessage message) async {
  await flutterLocalNotificationsPlugin
      .resolvePlatformSpecificImplementation<
          AndroidFlutterLocalNotificationsPlugin>()
      ?.createNotificationChannel(channel);
  await FirebaseMessaging.instance.setForegroundNotificationPresentationOptions(
    alert: true, // Required to display a heads up notification
    badge: true,
    sound: true,
  );
  RemoteNotification? notification = message.notification;
  AndroidNotification? android = message.notification?.android;

  // If `onMessage` is triggered with a notification, construct our own
  // local notification to show to users using the created channel.
  if (notification != null && android != null) {
    await openOffersPage(message);
    flutterLocalNotificationsPlugin.show(
      notification.hashCode,
      notification.title,
      notification.body,
      NotificationDetails(
        android: AndroidNotificationDetails(
          channel.id,
          channel.name,
          channelDescription: channel.description,
          icon: 'notification',
        ),
      ),
      payload: "offers",
    );
  }
  print("Handling a background message: ${message.messageId}");
}