Flutter is an open-source framework developed by Google for building beautiful, multi-platform applications for Android, iOS, Linux, macOS, Windows, Google Fuchsia, and the web from a single code base.
Flutter offers a wide range of widgets that are easy to customize. It is a very reliable framework in that it supports hot reload functionality. This functionality helps thousands of developers save time by allowing them to see changes made to their code in real time. Hot reload works by compiling only the changed code and then injecting it into the running app using Dart’s JIT(Just In Time) compiler. The Flutter framework now rebuilds the widget tree automatically and this in turn helps developers to experiment quickly, build user interfaces, add more features, and fix bugs. Flutter packages are a key part of the framework. Developers can provide additional functionality by easily integrating Dart packages from the powerful package management system called Pub. Some of the functionalities include network calls, state management, animation, navigation, and routing.
Below is a code snippet showing a Basic “Hello World” example:
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Hello World App',
home: Scaffold(
appBar: AppBar(
title: Text('Hello World'),
),
body: Center(
child: Text('Hello World!'),
),
),
);
}
}
This code creates a simple “Hello World” app which has a centered text widget that displays the string “Hello World!”
Flutter Benefits for App Development:
- Rapid iteration of the software development process — As discussed earlier, hot reload saves time by allowing developers to quickly and easily experiment with different features, and debug flutter applications. Unlike in hot restart, in hot reload, the app state is preserved as the code changes are loaded into the VM and the widget is rebuilt.
The following is an example of flutter code that illustrates the functionality of Hot Reload.
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'My App',
home: Scaffold(
appBar: AppBar(
title: Text('My App'),
),
body: Center(
child: Text('Hello, world!'),
),
),
);
}
}
2. High performance — Flutter uses an Ahead-of-Time(AOT) compiler that allows the compilation of native code ahead of time. This in turn reduces the amount of time it takes for a Flutter app to startup and improves performance.
Visually appealing UIs — The rich set of customizable layouts and widgets allows developers to build beautiful and also responsive user interfaces.
Cross-platform development — Flutter is designed to allow code reuse across operating systems such as iOS and Android. This enables developers to write code once and deploy it across different platforms. Flutter code is reusable 95% of the time. Before re-using a code, it is important to ensure that the quality of the code is up to the mark with reference to security, reliability, and maintainability. Cross-platform development brings a host of advantages including; time-saving, reduced development risks, lowered cost associated with app development, and prevents code bloat(the production of program code that is perceived as unnecessarily long and slow.)
Object orientation — Flutter uses Dart which is an Object Oriented Programming language. The object-oriented approach reduces programming complexity and helps carry out tasks simultaneously.
Major software development is done using OOP and most developers have experience with object-oriented development. This will certainly reduce the learning curve for such developers who are new to Flutter. Additionally, Flutter is free to use and it also provides documentation and tutorials that make it easy for developers to learn.
Flutter Widgets and Layouts
Widgets are the fundamental building blocks for creating the User Interface(UI) of your Flutter App. A widget may be considered a component of the user interface that enables user interaction. Creating user interfaces in Flutter involves another key element which is layouts. A layout is created by composing widgets to build more complex widgets. Layouts are essential in arranging widgets in a specific hierarchy.
Some of the frequently utilized widgets are;
AppBar: serves as a top app bar that typically displays the page title and other actions. It also provides navigation to other parts of the app.
FlatButton: displays a button that responds to user taps. It displays a flat button having no elevation or background color until it is pressed by the user.
Drawer: provides users with a hidden panel at the side of the screen that houses additional navigational options. This widget can be used to create a hidden side menu in a Flutter application.
MaterialApp: provides several common UI elements. It builds upon a WidgetApp by adding material design-specific functionality.
CupertinoApp: creates an application environment similar to MaterialApp. It also provides an implementation of the iOS style(Cupertino) design language and supports iOS-specific features such as navigation with the iOS back-swipe gesture — a feature most of you might have interacted with.
Flutter Development Tools
Let’s have a look at the popular IDEs, tools, and plugins one can use to develop Flutter apps.
Flutter SDK: Flutter Software Development Kit(SDK) is a set of tools, libraries, and documents that are used to build and run a Flutter app across platforms. It includes the Flutter framework, core libraries, and tools such as Dart SDK.
Android Studio: This is the official IDE recommended for developing Flutter applications. Android Studio has a plugin for Flutter (Flutter plugin for Android Studio) that provides a visual editor, auto-completion, debugging tools, and many more features for developing, testing, and deploying Flutter applications effectively.
To get started with Flutter development in Android Studio, you will need to install the Flutter plugin from the plugin marketplace. The same step is applied when installing the Flutter extension in VS Code.
3. VS Code: VS Code is a powerful code editor for developing Flutter applications. It is a popular choice among Flutter developers due to its lightweight and customizable interface, vast library of extensions, and ease of integration with Flutter and Dart SDKs.
To write, test, and debug your Flutter code in VS Code, you first have to install the necessary extensions as mentioned earlier. You can also make use of the Flutter Inspector, which is a powerful tool in VS Code that allows you to inspect and debug widgets and their properties. VS Code also comes with IntelliSense, a powerful code-completion tool that can help you write and complete code faster.
- IntelliJ IDEA: If you would like to try something different, consider using IntelliJ IDEA which saves your time and improves your productivity. You will need to install the Flutter and Dart plugins before you start the development process of your Flutter applications. Additionally, you can perform hot reloads and make changes to your app in real time by use of the Flutter inspector. Use Live Templates in IntelliJ IDEA to save commonly used code snippets and easily insert them into your project when the need arises.
While Android Studio, IntelliJ IDEA, and VS Code are IDEs that provide an environment to code, SDKs provide the necessary libraries, resources, and tools to develop and run applications for a specific technology.
Flutter for Web
Flutter’s popularity in recent years can be attributed to its ability to develop excellent mobile applications for both iOS and Android platforms. However, Flutter can also be used to develop web applications following the release of Flutter 2 on March 3, 2021. This update saw through, the introduction of the official support for web-based applications with web-specific widgets. You do not need to learn HTML and CSS for Flutter as you do for React, Vue, Angular, and React Native. Flutter converts HTML/CSS code snippets to their Flutter/Dart code equivalents; nevertheless, Flutter is not designed to create traditional Single Page Applications (SPA) that rely on the browser’s Document Object Model (DOM) rendering.
Flutter can be used to create Progressive Web Applications (PWA) that can be both installed and run like a native mobile app. It is also worth highlighting that Flutter has a large, growing community of developers who actively contribute to the open-source framework to strengthen its capabilities and broaden its features.
State Management in Flutter
In Flutter, state refers to the data values that are used to define the behavior or output of a widget. The state of a widget can change dynamically based on the input, network responses, or any other factors to affect the behavior or appearance of the UI. Whether you are a seasoned Flutter developer or just starting, understanding the significance of state management is essential in designing high-quality applications. We will explore some of the approaches of state management in Flutter.
BLoC: BLoC or Business Logic Component is a popular approach, recommended by Google, that uses streams and sinks (don’t worry we’ll get to how these work) to manage state. The primary objective of the BLoC approach is to separate the view (UI) layer from the business logic layer.
A stream is an asynchronous sequence of data that is used to handle state changes within the BLoC pattern.
A sink is a way to add data to a stream. In simpler words, streams are used to represent the state of the app, and sinks are used to update the state. Events, such as user interactions, trigger the creation of new events or the modification of existing events, which are then sent to the BLoC through a sink. The BLoC updates its state based on the incoming events and notifies the UI of any changes using streams. When using BLoC, the app updates only when necessary, and this plays an important role in providing a smoother and more flawless user experience.
BLoC is a variation of the MVC model that came with Flutter upon its inception.
Provider: Provider state management approach is recommended in small to medium size state management. A good example of this is small projects which need to manage state in a more maintainable way.
With Provider, state management happens asynchronously and automatically. This means that any widget that relies on a piece of state will be updated whenever the state changes, without the need for manually updating the state. Provider offers simplicity, performance, and reduce boilerplate code.
setState: setState() is used to manage the state of a widget and triggers a rebuild of the whole widget tree that the widget is part of. However, this approach is only suitable for small to medium-sized apps that have simple state management needs as it can become difficult to manage in larger or more complex applications.
There are also other state management patterns/approaches in Flutter such as Redux, MobX, GetX, Scoped Model, Riverpod, and Flutter Bloc.
Flutter Vs React Native.
In this section, we’ll compare these two frameworks and help you decide which one is the right fit for your project. So, let’s dive in and explore!
Programming Language
React Native uses JavaScript while Flutter uses Dart, developed by Google. Although many developers are more familiar with JavaScript as compared to Dart, Dart has features that can make it easier to write and maintain complex code.
Performance
Flutter is well-designed to deliver high-performance, fast-rendering times. The credit goes to its use of a customizable rendering engine called Skia. On the flip side, React Native can have performance issues, especially in complex transitions and animations, and image loading and caching. In essence, if your app loads a lot of images, it can affect performance due to the time it takes to download and render images.
Development Experience
It is easier for starters and any developer to adopt and learn a new framework or technology where there is a large, engaging community. React Native has a large developer community, making it easier to learn and find resources. On the other hand, Flutter was introduced not so long ago and its developer community is not as large. Despite Flutter being a new player in the development landscape, its community is growing and highly active in sharing knowledge.
UI Components
React Native uses native components. That is to say that it uses the actual UI components provided by the operating system of the device. This allows React Native to create UI components that look and feel native to the device it’s running on, conversely, Flutter uses its own set of UI components called widgets, that are customized to look and feel native.
Ultimately, the choice between React Native and Flutter depends on various factors which should be evaluated carefully; project requirements, budget, timeline, preference of the developer, and the company.
Thank you for taking the time to read this comprehensive Flutter blog! I hope you found the information valuable and insightful. If you are ready to take the next step, I encourage you to put your new knowledge into practice and develop something amazing. Here, you can find a global community of Flutter developers and join them on the same journey.
I welcome any comments, questions, or feedback you may have on this blog post.
Keep learning and happy Fluttering!