I can't access the MediaQuery.of() in the MaterialApp widget within the themeData method referencing the screenHeight & screenWidth variables.
I've tried to wrap the HomeScreen widget within a MaterialApp widget itself followed by a Scaffold widget, but this did not help.
class MyApp extends StatelessWidget { MyApp({Key key}) : super(key: key); @override Widget build(BuildContext context) { final screenHeight = MediaQuery.of(context).size.height / 100; final screenWidth = MediaQuery.of(context).size.width / 100; return MaterialApp( title: 'MyApp', theme: ThemeData( primaryColor: Color.fromRGBO(231, 13, 61, 1), textTheme: new TextTheme( title: new TextStyle(color: Colors.black, fontWeight: FontWeight.bold, fontSize: screenHeight * 1.8,), body1: new TextStyle(color: Colors.black, fontSize: screenHeight * 1.8,), ), ), home: HomeScreen(), ); } } class _HomeScreen extends State { @override Widget build(BuildContext context) { return new Scaffold( appBar: new AppNavBar(), body: Container( color: Colors.white, child: ListView( children: <Widget> [ new Page1Widget(), Divider(height: 0, color: Colors.grey,), new Page2Widget(), ], ), ), bottomNavigationBar: new BottomNavBar(), ); } } flutter: ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════ flutter: The following assertion was thrown building MyApp(dirty): flutter: MediaQuery.of() called with a context that does not contain a MediaQuery. flutter: No MediaQuery ancestor could be found starting from the context that was passed to MediaQuery.of(). flutter: This can happen because you do not have a WidgetsApp or MaterialApp widget (those widgets introduce flutter: a MediaQuery), or it can happen if the context you use comes from a widget above those widgets. flutter: The context used was: flutter: MyApp(dirty)
