Flutter Provider simple counter example

	import 'package:flutter/material.dart';
	import 'package:provider/provider.dart';
	void main() {
	runApp(MyApp());
	}
	class MyApp extends StatelessWidget {
	// This widget is the root of your application.
	@override
	Widget build(BuildContext context) {
	return MaterialApp(
	title: 'Flutter Demo',
	theme: ThemeData(
	primarySwatch: Colors.blue,
	visualDensity: VisualDensity.adaptivePlatformDensity,
	),
	home: ChangeNotifierProvider(
	create: (context) => Counter(),
	child: MyHomePage(),
	),
	);
	}
	}
	class MyHomePage extends StatelessWidget {
	@override
	Widget build(BuildContext context) {
	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:',
	),
	Consumer<Counter>(
	builder: (context, counter, child) {
	return Text(
	"counter value is: ${counter.count}",
	style: Theme.of(context).textTheme.headline4,
	);
	},
	),
	new RaisedButton(
	padding: const EdgeInsets.fromLTRB(25, 15, 25, 15),
	textColor: Colors.white,
	color: Colors.blue,
	child: new Text("Reset Count"),
	onPressed: ()=> Provider.of<Counter>(context,listen: false).reset(),
	),
	],
	),
	),
	floatingActionButton: FloatingActionButton(
	tooltip: 'Increment',
	onPressed: () {
	Provider.of<Counter>(context, listen: false).increment();
	},
	child: Icon(Icons.add),
	),
	);
	}
	}
	class Counter extends ChangeNotifier {
	int count = 0;
	void increment() {
	count += 1;
	notifyListeners();
	}
	void reset(){
	count = 0;
	notifyListeners();
	}
	}

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