push_notifications.dart

import 'package:firebase_messaging/firebase_messaging.dart';

class PushNotificationsManager {

  PushNotificationsManager._();

  factory PushNotificationsManager() => _instance;

  static final PushNotificationsManager _instance = PushNotificationsManager._();

  final FirebaseMessaging _firebaseMessaging = FirebaseMessaging();
  bool _initialized = false;

  Future<void> init() async {
    if (!_initialized) {
      // For iOS request permission first.
      _firebaseMessaging.requestNotificationPermissions();
      _firebaseMessaging.configure();

      // For testing purposes print the Firebase Messaging token
      String token = await _firebaseMessaging.getToken();
      print("FirebaseMessaging token: $token");
      
      _initialized = true;
    }
  }
}

@moreirapontocom

Future main() async {
  PushNotificationsManager().init(); <--

That's the way I do it.

Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();
  PushNotificationsManager().init();
  runApp(MyApp());
}

final FirebaseMessaging _firebaseMessaging = FirebaseMessaging();

_firebaseMessaging.requestNotificationPermissions();
_firebaseMessaging.configure();

These method calls not exist in latest flutter_message version.

firebase_messaging: ^10.0.5