[Flutter2Start - StatelessWidget vs StatefulWidget] #flutter2start

main.dart

// ignore_for_file: use_key_in_widget_constructors, prefer_const_constructors, prefer_const_literals_to_create_immutables

import 'package:flutter/material.dart';

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

class App extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: HomePage(),
    );
  }
}

class HomePage extends StatefulWidget {
  @override
  _HomePageState createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  int counter = 0;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Lista d'attesa!"),
        centerTitle: true,
      ),
      body: Center(
        child: Text(
          "Persone in lista d'attesa: $counter",
          style: TextStyle(
            fontSize: 20,
            fontWeight: FontWeight.bold,
          ),
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          setState(() {
            counter = counter + 1;
          });
        },
        child: Icon(Icons.plus_one),
      ),
    );
  }
}