Flutter DartPad starter code

starter_code.dart

import 'package:flutter/material.dart';

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

class DemoApp extends StatelessWidget {
  
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: Container(color: Colors.yellow),
      ),
    );
  }
}