Detect user selection a point on a line

I have been scratching my head all day long trying to find a solution to this problem.

First I draw a few multiple points line using Polyline(...).
Next, I need to detect user selection of any of these line plus I need to know exactly which point and which line he/she clicked on.

Tried to set the region of the lines but seemed that the region setting only applies to polygons, rects and other shapes.

PLEASE HELP!