Context.DataPointInfos[i].DataPoint.LayoutSlot was exactly what I needed, I don't understand how could i miss it. Thank you for pointing on that.
But I have another question. When moving with mouse cursor up and down and category is not changing then the event TrackInfoUpdated is not fired at all. This is intended behavior or bug?
Avneesh: As I understand DistanceToTouchLocation is calculated for X axis so all Context.DataPointInfos
have same value. If you need closest datapoint on Y axis, try something like that:
DataPointInfo closestDataPoint = e.Context.DataPointInfos.OrderBy(x => Math.Abs(e.Context.TouchLocation.Y - x.DataPoint.LayoutSlot.Y)).FirstOrDefault();