Flutter Service Locator

A lightweight and easy-to-use dependency injection package for Flutter applications.

Features

  • Simple API for registering and resolving dependencies
  • Support for both synchronous and asynchronous dependency resolution
  • Singleton and factory instance management
  • Built-in disposal mechanism for cleaning up resources
  • Minimal boilerplate code required

Installation

Add this to your package's pubspec.yaml file:

dependencies:
  flutter_service_locator: any

Then run:

$ flutter pub get

Usage

Setting up dependencies

import 'package:dart_service_locator/dart_service_locator.dart';

void setupDependencies() {
  // Register a synchronous dependency
  register<Logger>(() => ConsoleLogger());
  register<User>(() => User());

  // Register an asynchronous dependency
  register<Future<Database>>(() async {
    final db = Database();
    await db.initialize();
    return db;
  });

  // Register a dependency that relies on other dependencies
  register<Future<UserRepository>>(() async {
    final db = await locate<Future<Database>>();
    return UserRepository(db);
  });
}

Using dependencies

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

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return FutureBuilder<UserRepository>(
      future: locate<Future<UserRepository>>(),
      builder: (context, snapshot) {
        if (snapshot.connectionState == ConnectionState.done) {
          final userRepo = snapshot.data!;
          // Use userRepo
          return Text('User count: ${userRepo.getUserCount()}');
        } else {
          return CircularProgressIndicator();
        }
      },
    );
  }
}

Cleaning up

import 'package:dart_service_locator/dart_service_locator.dart';

clear();

API Reference

  • register<T>(T Function() creator): Register a synchronous dependency
  • locate<T>(): Get or create a locate instance of a dependency
  • create<T>(): Create a new instance of a dependency
  • remove<T>(): Remove a locate instance of a dependency
  • clear(): Clear all registered dependencies

Examples

For more advanced usage and examples, check out the example folder in the package repository.

Additional Information

For more information on using this package, please refer to the API documentation.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the BSD-3-Clause license - see the LICENSE file for details.

Libraries

dart_service_locator