Flutter - IconButton Widget

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  // This widget is the root
  // of your application
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(primarySwatch: Colors.blue),
      home: GFG(),
      debugShowCheckedModeBanner: false,
    );
  }
}

// This widget will be shown as the
// home page of your application.
class GFG extends StatefulWidget {
  const GFG({Key? key}) : super(key: key);

  @override
  State<GFG> createState() => _GFGState();
}

class _GFGState extends State<GFG> {
  int count = 0;
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text("GeeksForGeeks"),
        backgroundColor: Colors.green,
        foregroundColor: Colors.white,
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            // Creating a icon button
            IconButton(
              iconSize: 100,
              icon: const Icon(Icons.add),
              // the method which is called
              // when button is pressed
              onPressed: () {
                setState(() {
                  count++;
                });
              },
            ),
            // SizedBox used as the separator
            const SizedBox(height: 40),
            // Text widget used to display count
            Text("$count", style: TextStyle(fontSize: 50, color: Colors.blue)),
          ],
        ),
      ),
    );
  }
}