Use Conditional Statement In Child Widget Using Flutter

import 'package:flutter/material.dart';
import 'dart:io' show Platform;
void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      home: Scaffold(
          appBar: AppBar(
            backgroundColor: Colors.lightGreen,
            title: Text("Use Conditional Statement in Child Widget"),
          ),
          body: CustomView()
      ),
    );
  }
}

class CustomView extends StatefulWidget {
  CustomViewWidget createState() => CustomViewWidget();
}
class CustomViewWidget extends State {
  Widget _detectOS() {
    if (Platform.isAndroid) {
      return Container(
          width: 150.00,
          color: Colors.orange,
          padding: EdgeInsets.fromLTRB(20, 20, 20, 20),
          child: Text('Android Device OS Detected',
              textAlign: TextAlign.center,
              style: TextStyle(fontSize: 20, color: Colors.white)
          )
      );
    }
    else if (Platform.isIOS) {
      return Container(
          width: 150.00,
          padding: EdgeInsets.fromLTRB(20, 20, 20, 20),
          color: Colors.blueAccent,
          child: Text('iOS Device OS Detected',
              textAlign: TextAlign.center,
              style: TextStyle(fontSize: 20, color: Colors.white))
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
        home: Scaffold(
          body: Center(
              child: _detectOS()
          ),
        )
    );
  }
}