FirebaseNotificationsHandler For Flutter

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FirebaseNotificationsHandler is a simple and easy-to-use notifications handler for Firebase Notifications. It includes built-in support for local notifications, allowing your app to display notifications even when it's in the foreground with no extra setup. With customization options available, you can manage notification behavior seamlessly.

The package uses a widget-based approach, and exposes a widget to handle the notifications. This makes it feel like home for Flutter developers, as it integrates seamlessly with Flutter’s UI-driven architecture. With easy-to-use callbacks such as onTap, you can effortlessly manage and respond to notification taps and customize the notification behavior, providing a smooth integration process for any Flutter project.

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🗂️ Table of Contents

• 📷 Screenshots
• ✨ Features
• 🛫 Migration Guides
  • Migration Guide from v1.x to v2.x+
• 🚀 Getting Started
• 🛠️ Platform-specific Setup
  • Android
  • iOS
  • Web
• ❓ Usage
  • Creating notification channels for Android
  • Adding custom sound files in platform-specific folders
    • Android
    • iOS
• 💡 Solutions to common issues
  • Notification not showing as a pop up on Android device
  • Custom sound not playing when notification received on Android device
  • Notification image not showing if app in background or terminated even when passed on Android device
  • Custom sounds in Android work in debug mode but not in release mode
• 🎯 Sample Usage
• 👤 Collaborators

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📷 Screenshots

App In Foreground	App In Background	Expanded Notification

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✨ Features

• Foreground Notification Handling: The package allows you to manage notifications even when the app is in the foreground, without needing additional setup.
• Easy-to-use Callbacks: You can define custom callbacks when a notification is tapped (onTap), when a notification arrives when app open (onOpenNotificationArrive), etc., making the widget simple to use.
• Custom Sounds: The package supports custom notification sounds for both Android and iOS platforms.
• Automatic FCM Token Handling: Built-in functionality to automatically handle Firebase Cloud Messaging (FCM) token initialization and updates, ensuring seamless management of push notification tokens.
• Cross-Platform Support: It provides full support for both Android and iOS, ensuring a consistent experience across platforms.
• Widget-Based Approach: The package integrates well with Flutter’s UI-driven architecture, offering a widget-based solution for handling notifications.
• Stream Subscription for Notifications: Exposes various streams like notificationTapsSubscription, notificationArrivesSubscription allowing listening to important notification events and managing them easily with the provided NotificationInfo objects.
• Deep Customization: The package offers flexibility in customizing notification behavior, such as controlling which notifications are handled, defining custom actions for specific notifications, and setting platform-specific parameters for local notifications.
• Solutions for Common Issues: The README provides troubleshooting tips and solutions for commonly faced issues, such as notifications not appearing as pop-ups, custom sounds not working in release mode, and image handling limitations.

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🛫 Migration Guides

Migration Guide from v1.x to v2.x+

1. Renaming of Parameters and Callbacks

Several parameters and callbacks were renamed for clarity and consistency:

• NotificationTapDetails is now NotificationInfo.
• onFCMTokenInitialize is now onFcmTokenInitialize.
• onFCMTokenUpdate is now onFcmTokenUpdate.
• initializeFCMToken is now initializeFcmToken.
• requestPermissionsOnInit is now requestPermissionsOnInitialize.
• AppState.closed is now AppState.terminated.

2. Context and Navigator Key Removal

• Navigator Key: The navigatorKey parameter is no longer available in onTap and onOpenNotificationArrive. You’ll need to manage your own navigator key in your app. See the example app for more details on handling navigation.
• Context: Callbacks such as onFcmTokenInitialize and onFcmTokenUpdate no longer accept context. Ensure that any context-dependent logic is refactored.

3. Handling of Notifications

• NotificationInfo: The class NotificationTapDetails has been renamed to NotificationInfo. This class now includes the firebaseMessage parameter, providing more comprehensive information.
• onTap and onOpenNotificationArrive now return a NotificationInfo object, replacing the previous payload. The payload can still be accessed using the payload property of NotificationInfo.
• The notificationArrivesSubscription stream now returns NotificationInfo instead of just the payload.

4. Local Notifications Configuration

The configuration of local notifications has been refactored to use platform-specific getters in LocalNotificationsConfiguration:

• Android-specific parameters like channelId, channelName, and sound have been moved to localNotificationsConfiguration.androidConfig.
• iOS-specific parameters like sound have been moved to localNotificationsConfiguration.iosConfig.
• The notificationIdGetter function is now also part of the LocalNotificationsConfiguration.

5. FCM Token Changes

• The callback onFCMTokenRefresh has been removed. Use onFcmTokenUpdate instead to handle token updates.
• If you need to maintain your own stream of FCM tokens, you can do so manually in your app.

6. Notification Sending

• Removed: sendFcmNotification has been deprecated for sending notifications from the client side. You'll now need to send notifications using Firebase Cloud Messaging (FCM) server-side APIs.
• New: A new sendLocalNotification function is introduced, which allows sending or scheduling local notifications.

7. Other Notable Changes

• New streams notificationTapsSubscription and notificationArrivesSubscription are available for handling notification taps and arrivals.
• Android notification channel management methods have been added: create, read, and delete channels.
• New callbacks and getters such as permissionGetter, shouldHandleNotification, messageModifier, and stateKeyGetter are introduced for finer control over the notification lifecycle.
• Logging is now available in debug mode for better debugging.
• Fixed issues with images not displaying in notifications.
• getInitialMessage callback added for retrieving the initial notification that launched the app.

8. Updated Example App and Documentation

• The example app has been updated to use the latest SDKs and demonstrates how to implement these breaking changes.
• Documentation has been updated to reflect all changes, along with the issue tracker link for reporting bugs or issues.

For more details, refer to the CHANGELOG.

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🚀 Getting Started

Step 1: Create Firebase Project

Create a Firebase project. Learn more about Firebase projects here.

Step 2: Register your apps and configure Firebase

Add your Android & iOS apps to your Firebase project and configure the Firebase the apps by following the setup instructions for Android and iOS separately.

Step 3: Add firebase_core dependency

Add firebase_core as a dependency in your pubspec.yaml file.

dependencies:
  flutter:
    sdk: flutter

  firebase_core:

Step 4: Initialize Firebase

Call Firebase.initializeApp() in the main() method as shown to intialize Firebase in your project.

import 'package:firebase_core/firebase_core.dart';

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

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🛠️ Platform-Specific Setup

Android

Note

Refer to the platform specific setup for local notifications here

1. Add the following meta-data tags (if required) to define default values in AndroidManifest.xml under the <application> tag:

<!-- Can add a default notification channel (if not sending a channel id when sending notification) -->
<!-- If you don't specify a default channel id, and don't pass an id when sending notification, Android creates a default channel "Miscellaneous" -->
<meta-data
    android:name="com.google.firebase.messaging.default_notification_channel_id"
    android:value="default" />

<!-- Use the following tags if you need to different icons or color for app icon -->
<!-- <meta-data
    android:name="com.google.firebase.messaging.default_notification_icon"
    android:resource="@drawable/notification_icon" />

<meta-data
    android:name="com.google.firebase.messaging.default_notification_color"
    android:resource="@color/notification_color" /> -->

2. Add this <intent-filter> in the <activity> tag:

<intent-filter>
    <action android:name="FLUTTER_NOTIFICATION_CLICK" />
    <category android:name="android.intent.category.DEFAULT" />
</intent-filter>

iOS

Note

Refer to the platform specific setup for local notifications here

Web

1. Provide the vapidKey in FirebaseNotificationsHandler from the cloud messaging settings by generating a new Web push certificate.

2. Add this script tag in index.html after adding the firebase config script

<script>
if ("serviceWorker" in navigator) {
  window.addEventListener("load", function () {
    // navigator.serviceWorker.register("/flutter_service_worker.js");
    navigator.serviceWorker.register("/firebase-messaging-sw.js");
  });
}
</script>

3. Create a file firebase-messaging-sw.js in the web folder itself and paste the following contents. Add your own firebase app config here.

importScripts("https://www.gstatic.com/firebasejs/7.15.5/firebase-app.js");
importScripts("https://www.gstatic.com/firebasejs/7.15.5/firebase-messaging.js");

firebase.initializeApp(
    // YOUR FIREBASE CONFIG MAP HERE
);

const messaging = firebase.messaging();
messaging.setBackgroundMessageHandler(function (payload) {
    const promiseChain = clients
        .matchAll({
            type: "window",
            includeUncontrolled: true
        })
        .then(windowClients => {
            for (let i = 0; i < windowClients.length; i++) {
                const windowClient = windowClients[i];
                windowClient.postMessage(payload);
            }
        })
        .then(() => {
            return registration.showNotification("New Message");
        });
    return promiseChain;
});
self.addEventListener('notificationclick', function (event) {
    console.log('notification received: ', event)
});

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❓ Usage

1. Add firebase_notifications_handler as a dependency in your pubspec.yaml file.

dependencies:
  flutter:
    sdk: flutter

  firebase_notifications_handler:

2. Wrap the FirebaseNotificationsHandler widget ideally as a parent widget on the MaterialApp to enable your application to receive notifications.

import 'package:firebase_notifications_handler/firebase_notifications_handler.dart';

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return FirebaseNotificationsHandler(
      child: MaterialApp(),
    );
  }
}

Although, the widget automatically initializes the FCM token, but if the FCM token is needed before the widget is built, use the FirebaseNotificationsHandler.initializeFcmToken() function to initialize the token, which will initialize and return initialized token. This will also trigger the onFCMTokenInitialize callback.

3. Explore the widget documentation, and see the different configurations available, allowing you to customize each and every bit of your notifications.

FirebaseNotificationsHandler(
  localNotificationsConfiguration: LocalNotificationsConfiguration(
    androidConfig: AndroidNotificationsConfig(
      // ...
    ),
    iosConfig: IosNotificationsConfig(
      // ...
    ),
  ),
  onOpenNotificationArrive: (info) {
    log(
      id,
      msg: 'Notification received while app is open with payload ${info.payload}',
    );
  },
  onTap: (info) {
    final payload = info.payload;
    final appState = info.appState;
    final firebaseMessage = info.firebaseMessage;

    // If you want to push a screen on notification tap
    //
    // Globals.navigatorKey.currentState?.pushNamed(payload['screenId']);
    //
    // OR
    ///
    // Get current context
    // final context = Globals.navigatorKey.currentContext!;

    log(
      id,
      msg: 'Notification tapped with $appState & payload $payload. Firebase message: $firebaseMessage',
    );
  },
  onFcmTokenInitialize: (token) => Globals.fcmTokenNotifier.value = token,
  onFcmTokenUpdate: (token) => Globals.fcmTokenNotifier.value = token,
  // ...
);

Creating notification channels for Android

By default, if you send a notification, the device will automatically create a notification channel with the passed channelId, but the priority for that channel will be normal, and the notification will not show up as a popup.

Creating a default channel lets you set the priorty to high and also give you more customization of the channels like setting a custom notification sound, setting vibration patterns etc.

FirebaseNotificationsHandler.createAndroidNotificationChannel(
  const AndroidNotificationChannel(
    'marketing',
    'Marketing',
    description: 'Notification channel for marketing',
    playSound: true,
    importance: Importance.max,
    sound: RawResourceAndroidNotificationSound('marketing'),
  ),
);

It is recommended to create notification channels as soon as the app starts, as the custom sounds will not play if the channel is not created for the first time, and it might cause issues with other parameters as well.

FirebaseNotificationsHandler.createAndroidNotificationChannels([
  const AndroidNotificationChannel(
    'promotions',
    'Promotions',
    description: 'Notification channel for promotions',
    playSound: true,
    importance: Importance.max,
    sound: RawResourceAndroidNotificationSound('chime'),
  ),
  const AndroidNotificationChannel(
    'order-updates',
    'Order Updates',
    description: 'Notification channel for order updates',
    playSound: true,
    importance: Importance.max,
    sound: RawResourceAndroidNotificationSound('elevator'),
  ),
  const AndroidNotificationChannel(
    'messages',
    'Messages',
    description: 'Notification channel for messages',
    playSound: true,
    importance: Importance.max,
    sound: RawResourceAndroidNotificationSound('bell'),
  ),
]);

Adding custom sound files in platform-specific folders

Android

Important

Add a keep.xml file in the android/app/src/main/res/raw/ folder, as flutter strips off the raw folder when compiling app in release mode, and hence the custom sounds won't work in release mode.

• Add the audio file in the android/app/src/main/res/raw/ folder.

iOS

• Add the audio file in the ios/Runner/Resources/ folder.

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💡 Solutions to common issues

Notification not showing as a pop up on Android device:

On Android devices, a notification channel by default when a notification arrives, but that might not have the priority set to high. The notification only shows up as a popup if the channel you're sending it to has priority set as "high". We can solve this issue by creating a notification channel on app start using:

FirebaseNotificationsHandler.createAndroidNotificationChannel(
  const AndroidNotificationChannel(
    'default',
    'Default',
    importance: Importance.high,
  ),
);

Custom sound not playing when notification received on Android device:

On Android devices, a notification channel by default when a notification arrives, but that won't have the sound set to it by default. The sound will only play if the channel was creating while specifying the custom sound you want to play for that channel.

Note

You cannot modify a channel's sound after it's created. Only way is to either use a new channel id or delete an existing channel using FirebaseNotificationsHandler.deleteAndroidNotificationChannel(String channelId); and creating a new one with the new sound. Or try uninstalling the app and creating the channel again.

We can solve this issue by creating a notification channel on app start and passing in the sound using:

FirebaseNotificationsHandler.createAndroidNotificationChannel(
  const AndroidNotificationChannel(
    'default',
    'Default',
    playSound: true,
    importance: Importance.high,
    sound: RawResourceAndroidNotificationSound('pop'),
  ),
);

Notification image not showing if app in background or terminated even when passed on Android device:

The max size for a notification to be displayed by firebase on an Android device is 1MB (Source). So, if an image exceeds this size, it is not shown in the notification. However, if the app is in foreground, then there is no size limitation as then it's handled by local notifications.

Custom sounds in Android work in debug mode but not in release mode:

Flutter strips off the raw folder during compiling build for release mode. We can add a file keep.xml in the raw folder, which tells flutter to not strip off the raw folder, and hence fixing the issue.

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🎯 Sample Usage

See the example app for a complete app. Learn how to setup the example app for testing here.

Check out the full API reference of the widget here.

import 'package:firebase_core/firebase_core.dart';
import 'package:firebase_notifications_handler/firebase_notifications_handler.dart';
import 'package:flutter/material.dart';
import 'package:notifications_handler_demo/firebase_options.dart';
import 'package:notifications_handler_demo/screens/splash_screen.dart';
import 'package:notifications_handler_demo/utils/app_theme.dart';
import 'package:notifications_handler_demo/utils/globals.dart';
import 'package:notifications_handler_demo/utils/helpers.dart';
import 'package:notifications_handler_demo/utils/route_generator.dart';

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

class _MainApp extends StatelessWidget {
  static const id = '_MainApp';

  const _MainApp();

  @override
  Widget build(BuildContext context) {
    return FirebaseNotificationsHandler(
      localNotificationsConfiguration: LocalNotificationsConfiguration(
        androidConfig: AndroidNotificationsConfig(
            // ...
        ),
        iosConfig: IosNotificationsConfig(
            // ...
        ),
      ),
      shouldHandleNotification: (msg) {
        // add some logic and return bool on whether to handle a notif or not
        return true;
      },
      onOpenNotificationArrive: (info) {
        log(
          id,
          msg: 'Notification received while app is open with payload ${info.payload}',
        );
      },
      onTap: (info) {
        final payload = info.payload;
        final appState = info.appState;
        final firebaseMessage = info.firebaseMessage;

        /// If you want to push a screen on notification tap
        ///
        // Globals.navigatorKey.currentState?.pushNamed(
        //   payload['screenId'],
        // );
        ///
        /// or
        ///
        /// Get current context
        // final context = Globals.navigatorKey.currentContext!;

        log(
          id,
          msg: 'Notification tapped with $appState & payload $payload. Firebase message: $firebaseMessage',
        );
      },
      onFcmTokenInitialize: (token) => Globals.fcmTokenNotifier.value = token,
      onFcmTokenUpdate: (token) => Globals.fcmTokenNotifier.value = token,
      child: MaterialApp(
        debugShowCheckedModeBanner: false,
        title: 'FirebaseNotificationsHandler Demo',
        navigatorKey: Globals.navigatorKey,
        scaffoldMessengerKey: Globals.scaffoldMessengerKey,
        theme: AppTheme.lightTheme,
        darkTheme: AppTheme.darkTheme,
        onGenerateRoute: RouteGenerator.generateRoute,
        initialRoute: SplashScreen.id,
      ),
    );
  }
}

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👤 Collaborators

Name	GitHub	Linkedin
Rithik Bhandari	github/rithik-dev	linkedin/rithik-bhandari