simple_controller 1.3.0

A wrapper around StatefulWidget to make them easier to use and more reusable.

simple_controller

A lightweight and efficient state management solution for Flutter applications.

Features

• 🚀 Simple and intuitive API
• 🎯 Type-safe state management
• 📦 Minimal boilerplate
• 🔄 Reactive updates
• 💡 Easy to learn and implement

Usage

Key Components

SimpleController

A controller class that extends ChangeNotifier to manage dependencies and notify listeners.

SimpleControllerProvider

A widget that provides a single controller instance to its descendants. Use this when you need to provide a single controller to a widget subtree.

SimpleControllerProvider.multi

A widget that allows providing multiple controllers at once. Useful when you need to provide several controllers that work together.

context.use<T>()

A method to access a controller of type T from the widget tree. This provides type-safe access to your controllers from any descendant widget.

controller.build()

A method to efficiently rebuild widgets when specific controller state changes. It takes a selector function to specify which state to watch and a builder function to construct the widget.

Basic Example

class CounterController extends SimpleController {
  int count = 0;

  void increment() {
    count++;
    notifyListeners();
  }
}

class CounterProvider extends StatelessWidget {
  const CounterProvider({super.key});

  @override
  Widget build(BuildContext context) {
    return SimpleControllerProvider(
      create: (context) => CounterController(),
      child: const CounterWidget(),
    );
  }
}

class CounterWidget extends StatelessWidget {
  const CounterWidget({super.key});

  @override
  Widget build(BuildContext context) {
    final controller = context.use<CounterController>();
    return controller.build(
      select: (value) => value.count,
      builder: (context, value) => Text(value.toString()),
    );
  }
}

class CounterButton extends StatelessWidget {
  const CounterButton({super.key});

  @override
  Widget build(BuildContext context) {
    final controller = context.use<CounterController>();
    return TextButton(
      onPressed: () {
        controller.increment();
      },
      child: const Text('Increment'),
    );
  }
}

Advanced Usage

For more complex state management scenarios, you can:

class EnvController extends SimpleController {
  Env _env = Env.dev;
  Env get env => _env;

  SimpleControllerCommand<void, Env?> get setEnv => createCommand(_setEnv);

  void _setEnv(Env? env) {
    if (env == null) {
      return;
    }
    _env = env;
    notifyListeners();
  }
}

class MainAppController extends SimpleController {
  MainAppController({
    required EnvController envController,
  }) {
    addDependency(
      controller: envController,
      select: (value) => value.env,
      listen: _envControllerEnvListener,
    );
  }

  void _envControllerEnvListener(Env prev, Env next) {
    _countLength = switch (next) {
      Env.dev => 3,
      Env.uat => 2,
      Env.stg => 1,
      Env.prod => 0,
    };
    notifyListeners();
  }

  int _countLength = 1;
  int get countLength => _countLength;
}

class MainApp extends StatelessWidget {
  const MainApp({super.key});

  @override
  Widget build(BuildContext context) {
    return SimpleControllerProvider.multi(
      providers: [
        SimpleControllerProvider<EnvController>(
          create: (context) => EnvController(),
        ),
        SimpleControllerProvider<MainAppController>(
          create: (context) => MainAppController(
            envController: context.use(),
          ),
        ),
      ],
      child: MaterialApp(
        ...
      ),
    );
  }
}