Creating a Flutter Package: A Step-by-Step Guide

Flutter is a powerful platform for developing mobile applications, but it also provides the tools to create and distribute packages. A Flutter package is a reusable collection of code that can be easily shared and integrated into other projects. In this article, we’ll go through the process of creating a simple counter package for Flutter.

Step 1: Creating a New Flutter Package

To create a new Flutter package, open your preferred code editor (such as Android Studio or Visual Studio Code) and select “Create New Flutter Project”. Choose “Flutter Package” as the project type and give your package a name.

This will create a new directory for your package with the following files:

Folder Structure

Step 2: Creating the Counter Class

In the lib/ directory, create a new file called counter.dart. This file will contain the code for our Counter class.

class Counter {
  int _count = 0;

  int get count => _count;

  void increment() {
    _count++;
  }

  void decrement() {
    _count--;
  }
}

In this code, we define a Counter class that has an _count variable and two methods: increment() and decrement(). The increment() method increases the count by 1 and the decrement() method decreases the count by 1. The count property returns the current count value.

Step 3: Specifying Package Information in pubspec.yaml

The pubspec.yaml file is used to specify information about your package, such as its name, version, and dependencies. Open the pubspec.yaml file and add the following information:

name: counter_package
description: A new Flutter project.
version: 0.0.1

environment:
  sdk: '>=2.18.1 <3.0.0'
  flutter: ">=1.17.0"

dependencies:
  flutter:
    sdk: flutter

dev_dependencies:
  flutter_test:
    sdk: flutter
  flutter_lints: ^2.0.0
  
flutter:

In this code, we set the name, description, and version of our package. We also specify that our package depends on the Flutter SDK.

Step 4: Publishing Your Package

Before publishing your package, make sure to run the following command in the root directory of your package to ensure that all dependencies are up to date:

flutter packages get

To publish your package on pub.dev, you’ll need to create an account and an API token. Once you have these, run the following command:

flutter pub publish

This will upload your package to pub.dev and make it available for other developers to use.

Step 5: Using Your Package

To use your package in another Flutter project, add it as a dependency in the pubspec.yaml file:

dependencies:
  flutter:
    sdk: flutter
  counter_package: ^1.0.0

Then, import the package in your code:

import 'package:counter_package/counter.dart';

final counter = Counter();
counter.increment();
print(counter.count); // prints 1

Conclusion

In this article, we’ve covered the process of creating a simple counter package for Flutter. We’ve discussed creating a new Flutter package, defining a Counter class, specifying package information in the pubspec.yaml file, publishing the package on pub.dev, and using the package in another Flutter project.

By following these steps, you can create your own packages

Git repo is here