Flutter - GetX State Management Library

GetX is a fast, stable, and light state management library in Flutter that simplifies the process of managing and updating the state of your application. It is an alternative to other state management libraries in Flutter like MobX, BLoC, Redux, Provider, etc. GetX is also a powerful micro framework, and using this, we can manage states, complicated routing, and perform dependency injection. It handles the state of the app without boilerplate code.

Principles of GetX

1. Performance: As compared to other state management libraries, GetX is best because it consumes minimum resources. It do not uses Streams or ChangeNotifier and provides better performance.
2. Productivity: GetX’s syntax is easy, so it is productive. It saves a lot of time for the developers and increases the speed of the app because it does not use extra resources. It uses only those resources that are currently needed, and after its work is done, the resources will be freed automatically.
3. Organization: GetX code is organized as View, Logic, navigation, and dependency injection. So we don’t need any more context to navigate to other screen. We can navigate to screen without using the context so we are not dependent on widget tree.

Categories

• State Management: There are two types of state management:
  • Simple State Manager: It uses GetBuilder.
  • Reactive State Manager: It uses GetX and Obx.
• Route Management: If we want to make Widgets like Snackbar, Bottomsheets, dialogs, etc. Then we can use GetX for it because GetX can build these widgets without using context.
• Dependency Management: If we want to fetch data from another Class, then with the help of GetX, we can do this in just a single line of code. E.g.: Get.put()

Installation

To add the dependency to the pubspec.yaml file, add get as a dependency in the dependencies part of the pubspec.yaml file, as shown below:

dependencies:
     flutter:
       sdk: flutter
     get: ^4.7.2

Now, run the command below in the terminal.

flutter pub get

Or

Run the command below in the terminal.

flutter pub add get

Import get in the main.dart file

import 'package:get/get.dart';

Why use GetX?

• When we develop a flutter project without using GetX, after Flutter updates, various dependencies raise errors in the project. Many times it requires dedicated debugging to resolve the depracated issues, but with GetX, the only thing we need to do after the flutter update is updating the Get dependency.
• We all know that Flutter is fast, but there are things that need to be avoided like when navigating to another screen, we use Navigator.of(context).push(context, builder(.....)) and doing this so many times is not a good approach for a developer. Instead of writing this, we can simply write Get.to(HomePage()) to navigate to HomePage.
• When we want to update any Widget, we often use StatefulWidget for that. Instead of creating StatefulWidgets, we can do the same task using Stateless Widget also using GetX. Adding ".obs" to the variable which has to be updated, and placing the Widget inside Obx then we can update the screen when a variable changes the value without refresh the whole page.
• When we navigate between screens, create widgets like a snack bar, bottom sheets, etc. then we don't need to use context anymore. So due to GetX, performance increases.

Benefits of using GetX

1. Lightweight and efficient: GetX is incredibly lightweight and efficient, making it ideal for small to large-scale applications. It provides a reactive approach to state management that only rebuilds the parts of your UI that need updating, ensuring your application runs smoothly and efficiently.
2. Easy to learn: GetX has a small learning curve, making it easy for developers to learn and implement. It provides intuitive APIs that are easy to understand and use, making it an excellent choice for both beginner and experienced developers.
3. Built-in dependency injection: GetX includes built-in dependency injection, allowing you to easily manage dependencies within your application. This feature makes it easy to switch between dependencies and manage them across your application.
4. Great community support: GetX has a great community that is constantly contributing new features, bug fixes, and support for the library. The community is also very active on social media, making it easy to get help and support when you need it.
5. Simplicity: GetX results in a concise codebase since it removes the need for boilerplate code. Thus, it makes the code simple and easy to understand.

Let's take an example for navigation using GetX

• Normally, we use Navigator.push(context, MaterialPageRoute(builder: (context) => Home()),); to navigate to another screen. This task can also be done by using Get.to(Home());.

- main.dart:

import 'package:flutter/material.dart';
import 'package:get/get.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return GetMaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(primarySwatch: Colors.blue),
      home: First(),
      debugShowCheckedModeBanner: false,
    );
  }
}

class First extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("First Screen"),
        backgroundColor: Colors.black87,
        foregroundColor: Colors.white,
      ),
      body: Center(
        child: Container(
          child: ElevatedButton(
            style: ElevatedButton.styleFrom(
              backgroundColor: Colors.black87,
              foregroundColor: Colors.white,
            ),
            child: Text("Go to next screen"),
            onPressed: () {
              
              // Navigate to Second screen
              Get.to(Second());
            },
          ),
        ),
      ),
    );
  }
}

class Second extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Second Screen"),
        backgroundColor: Colors.green,
        foregroundColor: Colors.white,
      ),
      body: Center(
        child: Container(
          child: ElevatedButton(
            style: ElevatedButton.styleFrom(
              backgroundColor: Colors.green,
              foregroundColor: Colors.white,
            ),
            child: Text("Go to first screen"),
            onPressed: () {
              
              // Navigate to First screen
              Get.back();
            },
          ),
        ),
      ),
    );
  }
}

Output:

Conclusion

One of the crucial aspects of Flutter development is managing the application state efficiently. Getx is easy to learn and use, making it a favorite among Flutter developers. It lays the foundation for building robust and scalable applications. Its features are helpful in reducing the development time and satisfying customer needs. It is the top option among various state management when performance is the priority.

Is GetX suitable for large-scale Flutter applications?

Yes, it is suitable for handling complex and scalable apps.

Does GetX use BuildContext?

No, GetX eliminates need of BuildContext.