Flutter_local_notifications notificationResponse.payload is always empty string, - flutter

Question

I'm trying to setup my mobile app, so that when a user gets a FCM message, when they click on it, I can use data within the message to route them to appropriate screen.
My FCM message looks like this:
const fcmMessage = {
notification: {
title: title,
body: message
},
data:{
type:'Chat',
Name: 'Mike',
body:'test'
},
android: {
notification: {
title:title,
body: message,
channel_id:'high_importance_channel'
}
},
token: msgToken,
};
then within my main() method, I am initializing the Flutter_Local_notifications as per the code snippet below.
The issue is when I click on the notification, the payload is always an empty string?
These are the code lines that perform this. Why is the NotificationResponse.payload empty string?
ultimately, I need access the "data" object in the FCM message.
void onDidReceiveNotificationResponse(NotificationResponse notificationResponse) async {
print(notificationResponse.payload);
}
Here is the full main() method.
void main() async {
WidgetsFlutterBinding.ensureInitialized();
await Firebase.initializeApp();
// Set the background messaging handler early on, as a named top-level function
FirebaseMessaging.onBackgroundMessage(_firebaseMessagingBackgroundHandler);
if (!kIsWeb) {
channel = const AndroidNotificationChannel(
'high_importance_channel', // id
'High Importance Notifications', // title/
importance: Importance.high,
);
}
flutterLocalNotificationsPlugin = FlutterLocalNotificationsPlugin();
var initializationSettingsAndroid =
AndroidInitializationSettings('#mipmap/ic_launcher');
var initializationSettingsIOs = DarwinInitializationSettings();
var initSettings = InitializationSettings(
android: initializationSettingsAndroid, iOS: initializationSettingsIOs);
void onDidReceiveNotificationResponse(NotificationResponse notificationResponse) async {
print(notificationResponse.payload);
}
await flutterLocalNotificationsPlugin.initialize(initSettings,onDidReceiveNotificationResponse: onDidReceiveNotificationResponse,);
/// Create an Android Notification Channel.
/// We use this channel in the `AndroidManifest.xml` file to override the
/// default FCM channel to enable heads up notifications.
await flutterLocalNotificationsPlugin
.resolvePlatformSpecificImplementation<
AndroidFlutterLocalNotificationsPlugin>()
?.createNotificationChannel(channel);
await FirebaseMessaging.instance.setForegroundNotificationPresentationOptions(
alert: true,
badge: true,
sound: true,
);
FirebaseMessaging.onMessage.listen((RemoteMessage message) {
print('Got a message whilst in the foreground!');
print('Message data: ${message.data}');
if (message.notification != null) {
RemoteNotification? notification = message.notification;
AndroidNotification? android = message.notification?.android;
FlutterLocalNotificationsPlugin s = FlutterLocalNotificationsPlugin();
s.show(
notification.hashCode,
notification?.title,
notification?.body,
NotificationDetails(
android: AndroidNotificationDetails(channel.id, channel.name,
icon: 'launch_background',
channelDescription: channel.description,
importance: Importance.max,
priority: Priority.high,
ongoing: true,
styleInformation: BigTextStyleInformation('')),
),
);
}
});
runApp(MyApp());
}
UPDATE, found what I needed. In the LocalNotification show method, we can add the payload attribute and set it to whatever part of the message.
For my use case, I encode the message.data , and then in the didReceive method, I can decode back to JSON object and use as needed.
s.show(
payload: jsonEncode(message.data),
notification.hashCode,
notification?.title,
notification?.body,
NotificationDetails(
android: AndroidNotificationDetails(channel.id, channel.name,
icon: 'launch_background',
channelDescription: channel.description,
importance: Importance.max,
priority: Priority.high,
ongoing: true,
styleInformation: BigTextStyleInformation('')),
),
);