xxxxxxxxxx
Size screenSize = WidgetsBinding.instance.window.physicalSize /2;
double width = screenSize.width;
double height = screenSize.height;
>>note screensize returns a value twice of MediaQuery.of(context).size
xxxxxxxxxx
FlutterView view = PlatformDispatcher.instance.views.first;
screenWidth = view.physicalSize.width / view.devicePixelRatio;
screenHeight = view.physicalSize.height / view.devicePixelRatio;