I was reviewing documentation for [setState](https://api.flutter.dev/flutter/widgets/State/setState.html) and it states

> 
> Notify the framework that the internal state of this object has
>  changed.
> 
> 
> 

I am guessing the doc really means to emphasis on **this**

> 
> Notify the framework that the internal state of ***this*** object has
>  changed.
> 
> 
> 

I tried an **empty** setState with the default generated code and it was able to trigger the notification.

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

void main() => runApp(MyApp());

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

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    _counter++; // moved it out of setState
    setState(() {
//  _counter++; // instead setting it before setState
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.display1,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ),
    );
  }
}

```

above code does work fine,but all the examples I am finding on internet are explicitly changing the values or doing some activities withing setState, is it really necessary ?