Creating a view & view controller

import 'package:flutter/material.dart';
import 'package:get_it/get_it.dart';
import 'package:is_web_enabled/base_view.dart';

GetIt locator = GetIt.instance;

void setupLocator() {
  locator.registerFactory(() => MyHomePageController()); // This line would be placed in locator.dart
}

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
        visualDensity: VisualDensity.adaptivePlatformDensity,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatelessWidget {
  final String title;

  MyHomePage({this.title});

  @override
  Widget build(BuildContext context) {
    return BaseView<MyHomePageController>(
      onControllerReady: (controller) {
        controller.counter = 10;
      },
      builder: (context, controller, child) {
        return Scaffold(
          appBar: AppBar(
            title: Text(title),
          ),
          body: Center(
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: <Widget>[
                Text(
                  'You have pushed the button this many times:',
                ),
                Text(
                  '${controller.counter}',
                  style: Theme.of(context).textTheme.headline4,
                ),
              ],
            ),
          ),
          floatingActionButton: FloatingActionButton(
            onPressed: controller.onIncrementFabPressed,
            tooltip: 'Increment',
            child: Icon(Icons.add),
          ),
        );
      },
    );
  }
}

class MyHomePageController extends ChangeNotifier {
  int _counter;
  int get counter => _counter;
  set counter(int value) {
    if (_counter == value) return;
    _counter = value;
    notifyListeners();
  }

  onIncrementFabPressed() {
    counter++;
  }
}