public void OnPointerDown(PointerEventData eventData)
        {
            // Debug.Log("OnPointerDown:");
            _isPointerDown = true;

            if (mode == Mode.SEEK)
            {
                player.SetSeeking(true);
                _isPlaying = player.IsPlaying();
                if (_isPlaying)
                {
                    player.Pause();
                }
            }

            _UpdateDrag();
        }