Sample Code
class MyApp extends StatelessWidget { const MyApp({Key? key}) : super(key: key);
// This widget is the root of your application. @override Widget build(BuildContext context) { return MaterialApp( title: 'Flutter Responsive Builder', theme: ThemeData( primarySwatch: Colors.blue, ), home: ResponsiveBuilder( mobile: Container(), // Write code for Mobile view (Its Required) web: Container(), // Write code for Web view (Its Required) desktop: Container(),// Write code for Destop view tablet: Container(), // Write code for Tablet view ), ); } }