[Flutter] FCM message not shown when app is closed in release mode

I have used FCM along with Flutter local notification for receiving messages. Flutter local notifiation is used to show notification when app is in foreground.

When I terminate the application and send a message from Firebase Console, the below message appears in the logcat.

[ERROR:flutter/lib/ui/dart_runtime_hooks.cc(38)] Dart Error: Dart_LookupLibrary: library 'package:x/x/x/data/firebase_api.dart' not found.

E/flutter ( 9510): [ERROR:flutter/shell/common/shell.cc(117)] Dart Error: Dart_LookupLibrary: library 'package:x/x/x/data/firebase_api.dart' not found.

E/flutter ( 9510): [ERROR:flutter/shell/common/shell.cc(117)] Dart Error: Dart_LookupLibrary: library 'package:x/x/x/data/firebase_api.dart' not found.
​

This is my class:

class FirebaseAPI {

final _firebaseMessaging = FirebaseMessaging.instance;

final _localNotification = FlutterLocalNotificationsPlugin();



// Notification channel (Android only)

final AndroidNotificationChannel _androidNotificationChannel = const AndroidNotificationChannel(

'high_importance_channel',

'High Importance Notifications',

description: 'This channel is used for important notifications.',

importance: Importance.high,

);



FirebaseAPI() {

// Initialize Firebase Messaging and Local Notification

initNotification();

}



// Background message handler (needs to be a top-level function)

static Future<void> handleBackgroundMessage(RemoteMessage message) async {

print('Background Message Received: payload ${message.data}');



// Extract title and body from the data payload

String title = message.data['title_en'] ?? 'Default Title';

String body = message.data['body_en'] ?? 'Default Body';



final localNotifications = FlutterLocalNotificationsPlugin();

await localNotifications.show(

message.notification?.hashCode ?? 0,

title,

body,

NotificationDetails(

android: AndroidNotificationDetails(

'high_importance_channel',

'High Importance Notifications',

channelDescription: 'This channel is used for important notifications.',

importance: Importance.high,

priority: Priority.high,

icon: '@mipmap/aa', // Ensure this icon exists in your resources

),

),

payload: jsonEncode(message.data),

);

}

// Listen to messages when the app is closed





// Foreground message handler

Future<void> handleMessage(RemoteMessage message) async {

print('Foreground Message Received: payload ${message.data}');



// Extract title and body from the data payload

String title = message.data['title_en'] ?? 'Default Title';

String body = message.data['body_en'] ?? 'Default Body';



await _showLocalNotification(title, body);

}



// Show local notification function

Future<void> _showLocalNotification(String title, String body) async {

await _localNotification.show(

DateTime.now().millisecondsSinceEpoch ~/ 1000, // Unique ID

title,

body,

NotificationDetails(

android: AndroidNotificationDetails(

_androidNotificationChannel.id,

_androidNotificationChannel.name,

channelDescription: _androidNotificationChannel.description,

importance: Importance.high,

priority: Priority.high,

icon: '@mipmap/aa', // Ensure this icon exists in your resources

),

),

);

}



// Initialize local notification settings

Future<void> initLocalNotification() async {

const AndroidInitializationSettings androidInitSettings = AndroidInitializationSettings('@mipmap/ic_launcher');

const InitializationSettings initSettings = InitializationSettings(android: androidInitSettings);



await _localNotification.initialize(initSettings);

await _localNotification

.resolvePlatformSpecificImplementation<AndroidFlutterLocalNotificationsPlugin>()

?.createNotificationChannel(_androidNotificationChannel);

}



// Initialize push notifications with Firebase

Future<void> initPushNotification() async {

// Set foreground notification presentation options for iOS (if applicable)

await _firebaseMessaging.setForegroundNotificationPresentationOptions(

alert: true,

badge: true,

sound: true,

);



// Set up background message handler

FirebaseMessaging.onBackgroundMessage(handleBackgroundMessage);



// Listen to messages when the app is in the foreground

FirebaseMessaging.onMessage.listen(handleMessage);



// Listen to messages that open the app when tapped

FirebaseMessaging.onMessageOpenedApp.listen(handleMessage);

}



// Complete notification initialization

Future<void> initNotification() async {

// Request notification permissions

await _firebaseMessaging.requestPermission();



// Get the device token (optional)

String? token = await _firebaseMessaging.getToken();

print("Device Token: $token");



// Initialize local and push notifications

await initLocalNotification();

await initPushNotification();

}



// Retrieve device token (for sending notifications via server)

Future<String?> getDeviceToken() async {

String? token = await _firebaseMessaging.getToken();

return token;

}

}


Does anyone have an idea on how to fix this problem?

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