setSubtitle method
Sets a subtitle from the list obtained from getSubtitles. If no value is given or the subtitle is invalid (not found in the list), subtitles will be turned off
trackJsonStringobtained from getSubtitles
Implementation
Future<void> setSubtitle(String trackJsonString) async {
await _methodChannel.invokeMethod<void>('setSubtitle', trackJsonString);
}