material_app.dart

import 'package:flutter/cupertino.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';

@override
  Widget build(BuildContext context) {
    return new MaterialApp(
      debugShowCheckedModeBanner: false,
      home: new Scaffold(
        appBar: new AppBar(primary: true, title: new Text('Flutter-Start')),
        body: new Container(
          child: new Center(
            child: new Text('Center Widget'),
            ),
          ),
      theme: defaultTargetPlatform == TargetPlatform.iOS
          ? Themes.kIOSTheme
          : Themes.kDefaultTheme,
    );
  }