In any modern app, push notifications play a crucial role in interacting with users. In Flutter, the Firebase Cloud Messaging (FCM) library is used to implement push notifications. This chapter of our e-book course 'How to create applications from scratch to advanced using Flutter and Dart complete course' will expose you to the concept of Push Notifications in Flutter with Firebase and how to implement data persistence.
Push notifications are messages that can be sent directly to a user's mobile device from the server. These notifications are an effective way to keep users engaged with your app. Firebase Cloud Messaging is a free service that allows you to send notifications and messages to your users across multiple environments - Android, iOS or the web.
To start working with push notifications in Flutter, you need to configure Firebase first. To do this, create a new Firebase project, add an Android app to your Firebase project, download and place the 'google-services.json' file in your app folder. Then add the Firebase dependencies to your 'pubspec.yaml' file.
After that, you can start implementing the push notification functionality. First, you need to initialize Firebase in your app. This can be done using the 'Firebase.initializeApp()' function. Next, you need to request permissions to display notifications if you're on an iOS device. This can be done using the 'requestNotificationPermissions' function.
Now, to receive push messages, you need to get the Firebase Messaging instance and configure the event listeners. The 'onMessage' method is called when the app is in foreground and receives a push message. The 'onLaunch' method is called when the app is opened from a push notification. The 'onResume' method is called when the app is in the background and is opened from a push notification.
To send push notifications, you can use the Firebase console or the Firebase Server API. In the Firebase console, you can send notifications to all users or specific segments of users. With the Server API, you can send notifications to specific devices.
In addition to push notifications, data persistence is another important concept in application development. Data persistence allows user data to be saved and retrieved even after the application is closed or the device is turned off. In Flutter, you can implement data persistence using the 'shared_preferences' package.
The 'shared_preferences' package allows you to save simple data like integers, doubles, booleans and strings. To use this package, you need to add it to your 'pubspec.yaml' file. You can then use the 'SharedPreferences' class to save and retrieve data.
To save data, you can use the 'setInt', 'setDouble', 'setBool' and 'setString' methods. To retrieve data, you can use the 'getInt', 'getDouble', 'getBool' and 'getString' methods. You can also use the 'remove' method to remove a value.
In summary, push notifications and data persistence are essential concepts in Flutter app development. Push notifications allow you to effectively communicate with your users, while data persistence ensures that user data is securely saved. With Firebase and the 'shared_preferences' package, you can easily implement these functionalities in your Flutter application.
We hope this chapter of our e-book course has given you a clear understanding of how to implement push notifications and data persistence in Flutter. We'll continue to explore more advanced topics in future chapters. Stay tuned!
