Flutter: redux簡單使用

• Pub redux
• flutter_redux

import 'package:flutter/material.dart';
import 'package:redux/redux.dart';
import 'package:flutter_redux/flutter_redux.dart';

// 一個簡單的動做：增量
enum Actions { Increment }

void main() {
  // reducer + initState = store
  final store = Store<int>((int state, dynamic action) {
    if (action == Actions.Increment) {
      return state + 1;
    }

    return state;
  }, initialState: 0);
  runApp(new MyApp(store: store));
}

class MyApp extends StatelessWidget {
  MyApp({Key key, this.store}) : super(key: key);
  final Store<int> store;

  @override
  Widget build(BuildContext context) {
    return StoreProvider<int>(
      // 將給定的Redux Store傳遞給請求它的全部後代
      store: store,
      child: MaterialApp(
        home: MyHome(),
      ),
    );
  }
}

class MyHome extends StatefulWidget {
  @override
  _MyHomeState createState() => _MyHomeState();
}

class _MyHomeState extends State<MyHome> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Hello'),
      ),
      floatingActionButton: StoreConnector<int, VoidCallback>(
        converter: (store) => () => store.dispatch(Actions.Increment),
        builder: (context, cb) => FloatingActionButton(
              onPressed: cb,
              child: Icon(Icons.add),
            ),
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: <Widget>[
          StoreConnector<int, String>(
              converter: (store) => store.state.toString(),
              builder: (context, count) {
                return Center(child: Text('$count'));
              }),
        ],
      ),
    );
  }
}