library universal_ui; import 'package:flutter/foundation.dart'; import 'fake_ui.dart' if (dart.library.html) 'real_ui.dart' as ui_instance; class PlatformViewRegistryFix { registerViewFactory(dynamic x, dynamic y) { if (kIsWeb) { // ignore: undefined_prefixed_name ui_instance.platformViewRegistry.registerViewFactory( x, y, ); } else {} } } class UniversalUI { PlatformViewRegistryFix platformViewRegistry = PlatformViewRegistryFix(); } var ui = UniversalUI();