constraining drawn 2d with generated Elements

I'm learning drafting in Catia..
I'm unable to generate constrains between the 2D element and the generated drawing.
is there some setting in the tools>options to be modified or ??

I'm drawing a 2D line near the generated element and try to constrain it se follows.
select geometric selection command
select the 2D line
and try to pick the generated element .
where I fine a (-) symbol when I hover over the lines of the generated element..
and I'm unable to select it

1 Answer

Make sure the line has been drawn in the correct view. The situation you described will happen when trying to constrain objects in different drawing views.