How to implement notification in flutter

configure_notification.dart

 _configureNotification(){
    FirebaseMessaging _firebaseMessaging = FirebaseMessaging();
    _firebaseMessaging.configure(
      onMessage: (Map<String, dynamic> message) async {
        print("onMessage");
        print(message);
        if(Platform.isIOS){
          if(message["aps"] != null){
            NotificationService.showNotification(message["aps"]["alert"]["title"],
                          message["aps"]["alert"]["body"]);
          } else {
            NotificationService.showNotification(message["notification"]["title"],
              message["notification"]["body"]);
          }
        } else {
          NotificationService.showNotification(message["notification"]["title"],
              message["notification"]["body"]);
        }
      },
      onResume: (Map<String, dynamic> message) async {
        print("onResume");
        print(message);
        if(Platform.isIOS){
          if(message["aps"] != null){
            NotificationService.showNotification(message["aps"]["alert"]["title"],
                          message["aps"]["alert"]["body"]);
          } else {
            NotificationService.showNotification(message["notification"]["title"],
              message["notification"]["body"]);
          }
        } else {
          NotificationService.showNotification(message["notification"]["title"],
              message["notification"]["body"]);
        }
      },
      onLaunch: (Map<String, dynamic> message) async {
        print("onLaunch");
        print(message);
        if(Platform.isIOS){
          if(message["aps"] != null){
            NotificationService.showNotification(message["aps"]["alert"]["title"],
                          message["aps"]["alert"]["body"]);
          } else {
            NotificationService.showNotification(message["notification"]["title"],
              message["notification"]["body"]);
          }
        } else {
          NotificationService.showNotification(message["notification"]["title"],
              message["notification"]["body"]);
        }
      },
    );
    _firebaseMessaging.requestNotificationPermissions();
    _firebaseMessaging.getToken().then((token){
      print(token);
    });
  }

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

guide.md

How to Implement Firebase Cloud Messaging with Flutter

- Install and configure this package : https://pub.dev/packages/firebase_messaging#-readme-tab-
- Only Install this package : https://pub.dev/packages/flutter_local_notifications#-installing-tab-
- Add Notification Service file to your project files.
- Create ic_notification : https://romannurik.github.io/AndroidAssetStudio/index.html
- Copy ic_notification.png into android/app/src/main/res/drawable/ic_notification.png
- Implement _configureNotification() into your main screen
- Send your notification

notification_service.dart

import 'package:flutter_local_notifications/flutter_local_notifications.dart';

class NotificationService {

  static showNotification(String title , String body) async {

    FlutterLocalNotificationsPlugin _flutterLocalNotificationsPlugin = new FlutterLocalNotificationsPlugin();

    var initializationSettingsAndroid =
    new AndroidInitializationSettings('ic_notification');
    var initializationSettingsIOS = new IOSInitializationSettings();
    var initializationSettings = new InitializationSettings(
        initializationSettingsAndroid, initializationSettingsIOS);
    _flutterLocalNotificationsPlugin.initialize(initializationSettings);

    var androidPlatformChannelSpecifics = new AndroidNotificationDetails(
        '0', 'Nome do App', 'Canal de Notificações',
        importance: Importance.Max, priority: Priority.High , color: YOUR_COLOR_PRIMARY);

    var iOSPlatformChannelSpecifics = new IOSNotificationDetails();

    var platformChannelSpecifics = new NotificationDetails(
        androidPlatformChannelSpecifics, iOSPlatformChannelSpecifics);

    await _flutterLocalNotificationsPlugin.show(
        0, title, body, platformChannelSpecifics,
        payload: 'Notificação');
  }

}