Flutter firebase_messaging + flutter_local_notification

app.dart

import 'package:app_name/bloc/authentication/authentication_bloc.dart';
import 'package:app_name/services/local_notification.dart';
import 'package:app_name/view/authentication/AuthenticationInit.dart';
import 'package:app_name/view/authentication/login.dart';
import 'package:app_name/view/main.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:firebase_messaging/firebase_messaging.dart';
import 'bloc/blocList.dart';

Future<dynamic> onBackgroundMessage(Map<String, dynamic> message) {
  return LocalNotification.showNotification(message);
}


class MainApp extends StatefulWidget {
  // This widget is the root of your application.
  @override
  _MainAppState createState() => _MainAppState();
}

class _MainAppState extends State<MainApp> {
  final GlobalKey<NavigatorState> navigatorKey = GlobalKey(debugLabel: "Main Navigator");

  /// Handling notification message on background.
  _MainAppState() {
    /**
     * FCM Service Register on Main App State
     */
    FirebaseMessaging.onMessage.listen((RemoteMessage message) {
      LocalNotification.showNotification(message);
    });
    FirebaseMessaging.onMessageOpenedApp.listen((RemoteMessage message) {
      LocalNotification.showNotification(message);
    });
    FirebaseMessaging.onBackgroundMessage(onBackgroundMessage);
  }


  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    final GlobalKey<NavigatorState> navigatorKey = GlobalKey(debugLabel: "Main Navigator");
    return Container(
      color: Colors.white,
      child: MultiBlocProvider(
          providers: BlocList().generate(context),
          child: BlocBuilder<AuthenticationBloc, AuthenticationState>(
            builder: (context, state) {
              if(state is AuthenticationInitial) {
                context.bloc<AuthenticationBloc>().add(AuthenticationCheck());
                return AuthViewInit();
              } else if (state is Authenticated) {
                LocalNotification().notificationHandler(navigatorKey);
                FirebaseMessaging.instance.subscribeToTopic('pemberitahuan');
                if(state.authUser.jabatan.isOffice == 1) {
                  FirebaseMessaging.instance.subscribeToTopic('office');
                } else {
                  FirebaseMessaging.instance
            .subscribeToTopic('outfield-${authPayload.jabatan.id.toString()}');
                }
                return MainView(navigatorKey);
              } else if (state is Unauthenticated) {
                FirebaseMessaging.instance.deleteToken();
                return MaterialApp(
                  title: 'App Client Manager',
                  home: LoginView(),
                );
              } else {
                return MaterialApp(
                  title: 'App Client Manager',
                  home: Scaffold(
                    body: Center(
                        child: Text('No route defined'),
                  ))
                );
              }
            },
          )
      ),
    );
  }
}

local_notification.dart

import 'dart:convert';

import 'package:flutter_local_notifications/flutter_local_notifications.dart';
import 'package:flutter/material.dart';

import 'notification_navigate.dart';

final FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin = FlutterLocalNotificationsPlugin();

class LocalNotification {
  static Future<void> showNotification(RemoteMessage payload) async {
    final dynamic data = jsonDecode(payload.data['data']);
    final dynamic notification = jsonDecode(payload.data['notification']);
    const AndroidNotificationDetails androidPlatformChannelSpecifics = AndroidNotificationDetails(
        'BBD', 'Notification', 'All Notification is Here',
        importance: Importance.max,
        priority: Priority.high,
        ticker: 'ticker');
    final int idNotification = data['id'] != null ? int.parse(data['id']) : 1;
    const NotificationDetails platformChannelSpecifics = NotificationDetails(android: androidPlatformChannelSpecifics);
    await flutterLocalNotificationsPlugin.show(
        idNotification, notification['title'], notification['body'], platformChannelSpecifics,
        payload: data['type']);
  }

  Future<void> notificationHandler(GlobalKey<NavigatorState> navigatorKey) async {
    const AndroidInitializationSettings initializationSettingsAndroid = AndroidInitializationSettings('logo_bbd_sm');
    final InitializationSettings initializationSettings = InitializationSettings(android: initializationSettingsAndroid);
    flutterLocalNotificationsPlugin.initialize(initializationSettings,
        onSelectNotification: (String payload) async {
          if (payload != null) {
            NavigatorNavigate().go(navigatorKey, payload);
          }
        });
  }
}

main.dart

import 'package:bbd_client/app.dart';
import 'package:flutter/material.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter_dotenv/flutter_dotenv.dart';
import 'package:path_provider/path_provider.dart';
import 'package:hive/hive.dart';

Future<void> main() async {
  /**
   *
   *  @MainApp() Go to app.dart to see main wrapper.
   *
   */
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();
  final appDocumentDirectory = await getApplicationDocumentsDirectory();
  Hive.init(appDocumentDirectory.path);
  await DotEnv().load('environment/.env');
  runApp(
    MainApp()
  );
}

MainScreen.dart

import 'package:flutter/material.dart';
import 'package:app_name/routes.dart';

class MainView extends StatefulWidget {
  final GlobalKey<NavigatorState> navigatorKey;

  MainView(this.navigatorKey);

  @override
  _MainViewState createState() => _MainViewState();
}

class _MainViewState extends State<MainView> with TickerProviderStateMixin  {
  AnimationController _controller;
  Animation<Offset> _animation;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      duration: Duration(milliseconds: 500),
      vsync: this,
    )..forward();
    _animation = Tween<Offset>(
      begin: const Offset(0, 50),
      end: const Offset(0, 0),
    ).animate(CurvedAnimation(
      parent: _controller,
      curve: Curves.fastLinearToSlowEaseIn,
    ));
  }

  @override
  void dispose() {
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return SlideTransition(
      position: _animation,
      child: MaterialApp(
        title: 'App Client Manager',
        debugShowCheckedModeBanner: false,
        navigatorKey: widget.navigatorKey,
        theme: ThemeData(
          primarySwatch: Colors.blue,
          visualDensity: VisualDensity.adaptivePlatformDensity,
          canvasColor: Colors.transparent
        ),
        initialRoute: '/',
        onGenerateRoute: Routes().onGenerateRoute,
      ),
    );
  }
}

notification_navigate.dart

import 'package:flutter/material.dart';

class NavigatorNavigate {
  go(GlobalKey<NavigatorState> navState, String type) {
    switch(type) {
      case 'login':
        navState.currentState.pushNamed('/');
        break;

      default:
        navState.currentState.pushNamed('error');
    }
  }
}

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