getBufferDuration method
Get the current amount of video that has been buffered.
获得当前视频已缓存的时间
Implementation
Future<double> getBufferDuration() async {
if (_isNeedDisposed) return 0;
await _initPlayer.future;
DoubleMsg doubleMsg = await _vodPlayerApi.getBufferDuration(PlayerMsg()..playerId = _playerId);
return doubleMsg.value ?? 0;
}