_YOfIndex
invalidRect.top = _YOfIndex(index);
_DrawPackage(updateRect, fPackages[index], _YOfIndex(index), index == fSelectedIndex);
ScrollTo(0, _YOfIndex(index));
float scrollPointY = (_YOfIndex(index) + fBandMetrics->Height()) - bounds.Height();
return _RectOfY(_YOfIndex(index));
return _YOfIndex(index);