toggle_buttons.dart

import 'package:flutter/material.dart';

void main() => runApp(MaterialApp(home: Test()));

class Test extends StatefulWidget {
  const Test({super.key});

  @override
  State<Test> createState() => _TestState();
}

class _TestState extends State<Test> {
  List<bool> isSelected = [true, false, false];

  void onPressed(int index) {
    setState(() {
      for (int i = 0; i < isSelected.length; i++) {
        isSelected[i] = i == index;
      }
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: ToggleButtons(
          onPressed: (index) => onPressed(index),
          isSelected: isSelected,
          children: [
            Icon(Icons.local_cafe),
            Icon(Icons.fastfood),
            Icon(Icons.cake),
          ],
        ),
      ),
    );
  }
}