import 'package:flutter/material.dart';

class HelloRect extends StatelessWidget {
  final String text;

  HelloRect({this.text});

  @override
  Widget build(BuildContext context) {
    return Container(
      color: Colors.purple,
      width: 200,
      height: 200,
      margin: EdgeInsets.all(16),
      child: Center(child: Text(text)),
    );
  }
}

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Startup Name Generator',
      home: Scaffold(
        body: Center(
            child: HelloRect(text: 'Hi')
        )
      )
    );
  }
}