Radio button example

Here’s a simple example of using radio buttons in Flutter. It lets the user select one option from a group of choices

import 'package:flutter/material.dart';

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

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

class RadioButtonExample extends StatefulWidget {
  @override
  _RadioButtonExampleState createState() => _RadioButtonExampleState();
}

class _RadioButtonExampleState extends State<RadioButtonExample> {
  String selectedOption = 'Option 1';

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Radio Button Example')),
      body: Column(
        children: <Widget>[
          ListTile(
            title: Text('Option 1'),
            leading: Radio<String>(
              value: 'Option 1',
              groupValue: selectedOption,
              onChanged: (value) {
                setState(() {
                  selectedOption = value!;
                });
              },
            ),
          ),
          ListTile(
            title: Text('Option 2'),
            leading: Radio<String>(
              value: 'Option 2',
              groupValue: selectedOption,
              onChanged: (value) {
                setState(() {
                  selectedOption = value!;
                });
              },
            ),
          ),
          ListTile(
            title: Text('Option 3'),
            leading: Radio<String>(
              value: 'Option 3',
              groupValue: selectedOption,
              onChanged: (value) {
                setState(() {
                  selectedOption = value!;
                });
              },
            ),
          ),
          SizedBox(height: 20),
          Text(
            'Selected: $selectedOption',
            style: TextStyle(fontSize: 18),
          ),
        ],
      ),
    );
  }
}