@JS() library media_metadata; import 'package:js/js.dart'; @JS('MediaMetadata') class MediaMetadata { external MediaMetadata(MetadataLiteral md); } @JS() @anonymous class MetadataLiteral { external String get title; external String get album; external String get artist; external List get artwork; external factory MetadataLiteral( {String title, String album, String artist, List artwork}); } @JS() @anonymous class MetadataArtwork { external String get src; external String get sizes; external String get type; external factory MetadataArtwork({String src, String sizes, String type}); }