First Flutter gist

main.dart

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Title!'),
        ),
        body: Text('Center me!'),
      ),
    );
  }
}

solution.dart

import 'package:flutter_web/material.dart';
import 'package:flutter_web_ui/ui.dart' as ui;

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Title!'),
        ),
        body: Center(
          child: Text('Center me!'),
        ),
      ),
    );
  }
}

test.dart

import 'package:flutter_web/material.dart';
import 'package:flutter_web_ui/ui.dart' as ui;

void main() async {
  await ui.webOnlyInitializePlatform();
  runApp(MyApp());
}