Push notifications are an essential tool for keeping users engaged and informed about updates, new content or features. In Flutter, Firebase Cloud Messaging (FCM) is an effective solution for implementing push notifications in apps. In this chapter, we'll discuss the basic structure of a Flutter app and how to implement push notifications with Firebase.
Basic Structure of a Flutter Application
Before we jump into Firebase, it's important to understand the basic structure of a Flutter app. Flutter is Google's mobile UI toolkit that helps developers build native iOS and Android apps from a single codebase.
A Flutter app starts with a single dart file, usually called main.dart. This file contains the main() function, which is the entry point for the application. Within this function, you call runApp(), which inflates the provided widget and attaches it to the screen.
Widgets are the fundamental building block of the user interface in Flutter. They describe how the user interface should appear given the current configuration and state. Each widget is an immutable building block that can be combined with others to build complex user interfaces.
A typical Flutter app consists of a tree of widgets, with a root widget at the top that contains all the others. The MaterialApp widget is often used as the root of the widget tree. It provides many useful features like navigation and themes which are essential for most applications.
Push Notifications in Flutter with Firebase
To implement push notifications in a Flutter app, we need to use Firebase Cloud Messaging (FCM). FCM is a free service that allows you to send notifications to iOS, Android and web devices.
To start using FCM, you first need to create a Firebase project and register your app in it. After registering your app, you'll receive a configuration file that contains your app's Firebase credentials. This file must be added to your Flutter project.
After adding the configuration file, you can install the firebase_messaging library in your Flutter project. This library provides the API to interact with FCM.
To receive push notifications, you need to ask the user for permission. This can be done by calling the requestNotificationPermissions() method provided by the firebase_messaging library. Once permission is granted, you can get the device's FCM token by calling the getToken() method. This token is required to send notifications to the device.
To handle incoming notifications, you can configure notification handlers by calling the onMessage(), onResume(), and onLaunch() methods provided by the firebase_messaging library. These methods are called when a notification is received while the app is in the foreground, background, and not running, respectively.
To send notifications, you can use the Firebase Console web interface or the FCM API. In the Firebase console, you can manually create and send notifications. With the FCM API, you can programmatically send notifications from a backend server.
Implementing push notifications in a Flutter app with Firebase is a complex process involving many steps. However, the ability to keep users engaged and informed makes it well worth the effort. With the basic structure of a Flutter app and an understanding of how to use Firebase Cloud Messaging, you are well equipped to implement push notifications in your app.
