Note: Setup Flutter, FlutterFire, and Firebase Cloud Messaging with awesome notifications

import 'package:firebase_core/firebase_core.dart';
import 'firebase_options.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp(
    options: DefaultFirebaseOptions.currentPlatform,
  );
  runApp(MyApp());
}

// import 'dart:io';

import 'package:flutter/material.dart';
import 'package:firebase_core/firebase_core.dart';
import 'firebase_options.dart';

import 'package:awesome_notifications/awesome_notifications.dart';
import 'package:firebase_messaging/firebase_messaging.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();

  AwesomeNotifications().initialize('resource://drawable/notification_icon', [
    // notification icon
    NotificationChannel(
      channelGroupKey: 'basic_test',
      channelKey: 'basic',
      channelName: 'Basic notifications',
      channelDescription: 'Notification channel for basic tests',
      channelShowBadge: true,
      importance: NotificationImportance.High,
    ),
    //add more notification type with different configuration
  ]);

  //click listiner on local notification
  AwesomeNotifications()
      .actionStream
      .listen((ReceivedNotification receivedNotification) {
    debugPrint("ReceivedNotification");
    debugPrint(receivedNotification.payload!['title']);
    //output from local notification click.
  });

  await Firebase.initializeApp(
    options: DefaultFirebaseOptions.currentPlatform,
  );

  FirebaseMessaging.instance
      .subscribeToTopic("all"); //subscribe firebase message on topic

  FirebaseMessaging.onBackgroundMessage(firebaseBackgroundMessage);
  //background message listiner

  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

// Declared as global, outside of any class
Future<void> firebaseBackgroundMessage(RemoteMessage message) async {
  print("-- firebaseBackgroundMessage");
  AwesomeNotifications().createNotification(
      content: NotificationContent(
          //with image from URL
          id: 1,
          channelKey: 'basic', //channel configuration key
          title: message.data["title"],
          body: message.data["body"],
          displayOnForeground: true,
          // icon: message.data["icon"],
          // bigPicture: message.data["image"],
          // notificationLayout: NotificationLayout.BigPicture,
          payload: {"name": "flutter"}));
  print('Handling a background message ${message.messageId}');
}

Future<void> onFirebaseLaunchApp(RemoteMessage message) async {
  print("-- onFirebaseLaunchApp: $message");
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key, required this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  // FirebaseMessaging messaging = FirebaseMessaging.instance;

  int _counter = 0;

  @override
  void initState() {
    FirebaseMessaging.onMessage.listen(firebaseBackgroundMessage);
    // FirebaseMessaging.onMessageOpenedApp.listen(onFirebaseLaunchApp);

    FirebaseMessaging.onMessageOpenedApp.listen((RemoteMessage message) {
      _incrementCounter();
      var view = message.data["view"];
      print("-- onMessageOpenedApp: $view");
    });

    //active app listiner.
    super.initState();
  }

  void _incrementCounter() {
    setState(() {
      // This call to setState tells the Flutter framework that something has
      // changed in this State, which causes it to rerun the build method below
      // so that the display can reflect the updated values. If we changed
      // _counter without calling setState(), then the build method would not be
      // called again, and so nothing would appear to happen.
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
      appBar: AppBar(
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Center(
        // Center is a layout widget. It takes a single child and positions it
        // in the middle of the parent.
        child: Column(
          // Column is also a layout widget. It takes a list of children and
          // arranges them vertically. By default, it sizes itself to fit its
          // children horizontally, and tries to be as tall as its parent.
          //
          // Invoke "debug painting" (press "p" in the console, choose the
          // "Toggle Debug Paint" action from the Flutter Inspector in Android
          // Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
          // to see the wireframe for each widget.
          //
          // Column has various properties to control how it sizes itself and
          // how it positions its children. Here we use mainAxisAlignment to
          // center the children vertically; the main axis here is the vertical
          // axis because Columns are vertical (the cross axis would be
          // horizontal).
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            const Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: const Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

# Send to single device.
from pyfcm import FCMNotification
from datetime import datetime

API_KEY="put-api-key-here" 

push_service = FCMNotification(api_key=API_KEY)

# Your api-key can be gotten from:  https://console.firebase.google.com/project/<project-name>/settings/cloudmessaging

time_now = datetime.now().strftime("%Y/%m/%d %H:%M:%S")

registration_id = "<device registration_id>"
message_title = f"ทดสอบ at {time_now}"
message_body = "สวัสดีจอห์นชาวไร ข่าวที่คุณกำหนด สำหรับวันนี้พร้อมแล้ว"
click_action="",
message_icon="notification_icon"

message_image = 'https://www.fluttercampus.com/img/uploads/web/2021/02/c4ca4238a0b923820dcc509a6f75849b.webp'
# result = push_service.notify_single_device(registration_id=registration_id, message_title=message_title, message_body=message_body)

extra_notification_kwargs = {
  'image': message_image,
  'channelKey': "basic",
}

data_message = {
  'view': 'PAGE_LOCATION_ACTIVITY'
}

# Send a message to devices subscribed to a topic.
result = push_service.notify_topic_subscribers(
  topic_name="all", 
  message_title=message_title, 
  message_body=message_body, 
  extra_notification_kwargs=extra_notification_kwargs,
  data_message=data_message,
  message_icon=message_icon)

print(result)