Is it possible to record the path points of line?

[AmbroseChen]

I want to get the path points of lines (ex: [1,1],[2,2],[8,7]....).
It seems Lib doesn't have function like that.
I try to set setOnTouchListener to canvas.
It can return the path point, but canvas can't draw anymore.

If there any suggestion for this situation?

I solved this issue by create a new class extent Lib, and modified the onTouch fucntion.