initialize method
Implementation
@override
Future<void> initialize() async {
if (_textureId != null) {
return;
}
final response = await WebRTC.invokeMethod('createVideoRenderer', {});
_textureId = response['textureId'];
_eventSubscription = EventChannel('FlutterWebRTC/Texture$textureId')
.receiveBroadcastStream()
.listen(eventListener, onError: errorListener);
}