marcglasberg/asyncredux-provider-integration

Provider Integration with AsyncRedux

The provider_for_redux package bridges Provider and AsyncRedux, enabling you to use Provider's dependency injection with Redux state management.

Installation

Add the package to your pubspec.yaml:

dependencies:
  provider_for_redux: ^8.0.0

Setting Up AsyncReduxProvider

Replace StoreProvider with AsyncReduxProvider to expose three items to descendant widgets:

• The Redux store (Store<AppState>)
• The application state (AppState)
• The dispatch method (Dispatch)

import 'package:provider_for_redux/provider_for_redux.dart';

void main() {
  final store = Store<AppState>(initialState: AppState.initial());

  runApp(
    AsyncReduxProvider<AppState>.value(
      value: store,
      child: MaterialApp(home: MyHomePage()),
    ),
  );
}

Accessing State with Provider.of

Access store components directly using standard Provider patterns:

// Access state (rebuilds on state changes)
final counter = Provider.of<AppState>(context).counter;

// Access dispatch (use listen: false for actions)
Provider.of<Dispatch>(context, listen: false)(IncrementAction());

// Access the store directly
final store = Provider.of<Store<AppState>>(context, listen: false);

ReduxConsumer Widget

ReduxConsumer provides store, state, and dispatch in a single builder, simplifying access:

ReduxConsumer<AppState>(
  builder: (context, store, state, dispatch, child) {
    return Column(
      children: [
        Text('Counter: ${state.counter}'),
        Text('Description: ${state.description}'),
        ElevatedButton(
          onPressed: () => dispatch(IncrementAction()),
          child: Text('Increment'),
        ),
      ],
    );
  },
)

ReduxSelector Widget

ReduxSelector prevents unnecessary rebuilds by selecting specific state portions. Only when selected values change does the widget rebuild.

Using a List (Recommended)

The simplest approach - explicitly list the properties that should trigger rebuilds:

ReduxSelector<AppState, dynamic>(
  selector: (context, state) => [state.counter, state.description],
  builder: (context, store, state, dispatch, model, child) {
    return Column(
      children: [
        Text('Counter: ${state.counter}'),
        Text('Description: ${state.description}'),
        ElevatedButton(
          onPressed: () => dispatch(IncrementAction()),
          child: Text('Increment'),
        ),
      ],
    );
  },
)

Using a Custom Model

For structured data, use a Tuple or custom class:

ReduxSelector<AppState, Tuple2<int, String>>(
  selector: (context, state) => Tuple2(state.counter, state.description),
  builder: (context, store, state, dispatch, model, child) {
    return Column(
      children: [
        Text('Counter: ${model.item1}'),
        Text('Description: ${model.item2}'),
        ElevatedButton(
          onPressed: () => dispatch(IncrementAction()),
          child: Text('Increment'),
        ),
      ],
    );
  },
)

Choosing Between StoreConnector and ReduxSelector

Both approaches manage widget rebuilds during state changes, but serve different use cases:

Use StoreConnector When:

• You want to separate smart (store-aware) and dumb (presentational) widgets
• You need view-models with explicit equality comparison
• You're building reusable UI components that shouldn't know about Redux
• You want to test UI widgets in isolation without a store

class MyCounterConnector extends StatelessWidget {
  Widget build(BuildContext context) {
    return StoreConnector<AppState, ViewModel>(
      vm: () => Factory(this),
      builder: (context, vm) => MyCounter(
        counter: vm.counter,
        description: vm.description,
        onIncrement: vm.onIncrement,
      ),
    );
  }
}

class ViewModel extends Vm {
  final int counter;
  final String description;
  final VoidCallback onIncrement;

  ViewModel({
    required this.counter,
    required this.description,
    required this.onIncrement,
  }) : super(equals: [counter, description]);
}

Use ReduxSelector When:

• You prefer minimal boilerplate
• Direct store access within a single widget is acceptable
• You want Provider-style dependency injection
• You're integrating with existing Provider-based code

ReduxSelector<AppState, dynamic>(
  selector: (context, state) => [state.counter, state.description],
  builder: (context, store, state, dispatch, model, child) {
    return MyCounter(
      counter: state.counter,
      description: state.description,
      onIncrement: () => dispatch(IncrementAction()),
    );
  },
)

Migration Strategy

Both Provider and AsyncRedux connectors work simultaneously, enabling gradual migration:

// Old code using StoreConnector continues to work
class OldFeatureConnector extends StatelessWidget {
  Widget build(BuildContext context) {
    return StoreConnector<AppState, OldViewModel>(
      vm: () => OldFactory(this),
      builder: (context, vm) => OldFeatureWidget(vm: vm),
    );
  }
}

// New code can use ReduxSelector
class NewFeatureWidget extends StatelessWidget {
  Widget build(BuildContext context) {
    return ReduxSelector<AppState, dynamic>(
      selector: (context, state) => [state.newFeature],
      builder: (context, store, state, dispatch, model, child) {
        return NewFeatureContent(feature: state.newFeature);
      },
    );
  }
}

This allows you to migrate incrementally without rewriting your entire application.

Comparison Summary

| Aspect | StoreConnector | ReduxSelector | |--------|---------------|---------------| | Boilerplate | More (ViewModel + Factory) | Less (inline selector) | | Separation | Smart/Dumb widget pattern | Single widget | | Testing | Easy to test UI in isolation | Requires store setup | | Provider compatibility | Native AsyncRedux | Full Provider integration | | Rebuild control | Via ViewModel equality | Via selector list |

References

URLs from the documentation:

• https://asyncredux.com/sitemap.xml
• https://asyncredux.com/flutter/other-packages/using-the-provider-package
• https://asyncredux.com/flutter/connector/store-connector
• https://asyncredux.com/flutter/connector/connector-pattern
• https://asyncredux.com/flutter/basics/using-the-store-state
• https://asyncredux.com/flutter/miscellaneous/widget-selectors
• https://pub.dev/packages/provider_for_redux
• https://github.com/marcglasberg/provider_for_redux