Example app demonstrating the StateX class

statex_counter_app.dart

import 'package:flutter/material.dart';

import 'package:state_extended/state_extended.dart';

void main() => runApp(const MaterialApp(home: MyHomePage()));

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key, this.title = 'Flutter Demo Home Page'})
      : super(key: key);
  // Fields in a StatefulWidget should always be "final".
  final String title;
  @override
  State createState() => _MyHomePageState();
}

class _MyHomePageState extends StateX<MyHomePage> {
  _MyHomePageState() : super(Controller()) {
    con = controller as Controller;
  }
  late Controller con;

  @override
  Widget build(BuildContext context) => Scaffold(
        appBar: AppBar(
          title: Text(widget.title),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              const Text('You have pushed the button this many times:'),
              Text(
                '${con.data}',
                style: Theme.of(context).textTheme.headline4,
              ),
            ],
          ),
        ),
        floatingActionButton: FloatingActionButton(
          onPressed: con.onPressed,
          tooltip: 'Increment',
          child: const Icon(Icons.add),
        ),
      );
}

class Controller extends StateXController {
  // Using a factory constructor on Controllers and implementing the Singleton design pattern
  factory Controller() => _this ??= Controller._();
  Controller._()
      : model = _Model(),
        super();

  static Controller? _this;
  final _Model model;

  int get data => model.integer;

  void onPressed() => setState(() => model._incrementCounter());
}

class _Model {
  int get integer => _integer;
  int _integer = 0;
  int _incrementCounter() => ++_integer;
}