cyblock 0.0.1+2

A simple state management using dart stream. Cyblock is helper to use dart stream as state management, we can easily update data to listener with stream. it inject an event to run callback for mapping [...]

example/lib/main.dart

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

void main() {
  runApp(MyApp());
}

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: "Example app",
      home: HomeMainView(),
    );
  }
}

class HomeMainView extends StatefulWidget {
  @override
  _HomeMainViewState createState() => _HomeMainViewState();
}

class _HomeMainViewState extends State<HomeMainView> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Cyblock example"),
      ),
      body: SizedBox.expand(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            StreamBuilder<int>(
              stream: CounterCyblock.instance.stream,
              builder: (context, snapshot) {
                if(snapshot.connectionState == ConnectionState.waiting) {
                  CounterCyblock.instance.getState();
                  return Text("Not inserted yet");
                } else {
                  return Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: [
                      Text("The button is pressed :"),
                      Text(snapshot.data.toString(), style: TextStyle(fontSize: 25.0, fontWeight: FontWeight.bold)),
                    ],
                  );
                }
              },
            ),
            FlatButton(
              child: Text("Another page"),
              onPressed: () {
                Navigator.push(context, MaterialPageRoute(
                  builder: (_) => SecondPageMainView()
                ));
              },
            )
          ],
        ),
      ),
      floatingActionButton: Row(
        mainAxisAlignment: MainAxisAlignment.end,
        children: [
          FloatingActionButton(
            heroTag: "decrement",
            child: Icon(Icons.remove),
            onPressed: () {
              CounterCyblock.instance.insertEvent(DecrementEvent());
            },
          ),
          SizedBox(width: 10.0,),
          FloatingActionButton(
            heroTag: "increment",
            child: Icon(Icons.add),
            onPressed: () {
              CounterCyblock.instance.insertEvent(IncrementEvent());
            },
          )
        ],
      ),
    );
  }
}

class SecondPageMainView extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Second page"),
      ),
      body: Center(
        child: StreamBuilder<int>(
          stream: CounterCyblock.instance.stream,
          builder: (context, snapshot) {
            if(snapshot.connectionState == ConnectionState.waiting) {
              CounterCyblock.instance.getState();
              return CircularProgressIndicator();
            } else {
              return Text(snapshot.data.toString());
            }
          },
        ),
      ),
      floatingActionButton: Row(
        mainAxisAlignment: MainAxisAlignment.end,
        children: [
          FloatingActionButton(
            heroTag: "decrement",
            child: Icon(Icons.remove),
            onPressed: () {
              CounterCyblock.instance.insertEvent(DecrementEvent());
            },
          ),
          SizedBox(width: 10.0,),
          FloatingActionButton(
            heroTag: "increment",
            child: Icon(Icons.add),
            onPressed: () {
              CounterCyblock.instance.insertEvent(IncrementEvent());
            },
          )
        ],
      ),
    );
  }
}

/// Create cybloc
class CounterCyblock extends Cyblock<int, CounterEvent> {
  static final CounterCyblock _singleton = CounterCyblock._();
  CounterCyblock._() {
    initialState(0);
  }

  static CounterCyblock get instance => _singleton;

  @override
  void mapEventToState(CounterEvent event) {
    if(event is IncrementEvent) {
      emit(state+1);
    } else if(event is DecrementEvent) {
      emit(state-1);
    }
  }
}


/// Events
abstract class CounterEvent {}

class IncrementEvent extends CounterEvent {}

class DecrementEvent extends CounterEvent {}