Radio in Flutter

The Radio widget creates a radio button that allows the user to select one option from a group of options.
Here is a simple example of using the radio widget.

There Are Some Common Attributes for Radio widget

Here's a simple example of using a Radio widget Flutter:

File open lib->main.dart file −

import 'package:flutter/material.dart';

void main() {
  runApp(
    MyApp()
  );
}
class MyApp extends StatefulWidget{

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

class _MyAppState extends State<MyApp> {
  String _selectedOption = 'Option 1';

  void _handleRadioValueChanged(String value) {
    setState(() {
      _selectedOption = value;
    });
  }
  @override
  Widget build(BuildContext context) {
    return   MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          backgroundColor: Colors.blue,
          title: Text('StatefulWidget Example',
              style:TextStyle(fontSize: 20,color: Colors.white)),
        ),
        body:
        Column(
          mainAxisAlignment: MainAxisAlignment.center,

          children: [
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
            
              children: [
              Radio(
              value: 'Option 1',
              groupValue: _selectedOption,
              onChanged: (value) {
                _handleRadioValueChanged(value.toString());
              },
            ),
            Text('Option 1'),
            Radio(
              value: 'Option 2',
              groupValue: _selectedOption,
              onChanged: (value) {
                _handleRadioValueChanged(value.toString());
              },
            ),
            Text('Option 2'),
            Radio(
              value: 'Option 3',
              groupValue: _selectedOption,
              onChanged: (value) {
                _handleRadioValueChanged(value.toString());
              },
            ),
            Text('Option 3'),

            ],
                ),
            SizedBox(height: 16.0),
            Text('Selected Option: $_selectedOption'),
          ],
        ),
    ));

  }
}

Open Device Manager, run the emulator, and then run the application. Next, check the working output and check the output you declared in your code.

Output: