prepare method
Implementation
@override
Future<String?> prepare({
required ByteData? sf2,
String name = 'instrument.sf2',
}) async {
if (sf2 == null) return Future.value(null);
if (kIsWeb) return _channel.invokeMethod('prepare_midi');
File? _file = await writeToFile(sf2, name: name);
if (_file == null) return null;
return _channel.invokeMethod('prepare_midi', {'path': _file.path});
}