Checkbox in the FORM in the OrCAD PCB Designer

You can try do this like this:

(case fw->curField
("X"
something_1    
t)
("Y"
something_2    
nil
))

Tahnks!!

Additional Question:

I want to use the function axlSingleSelectBox(). For example if X then axlSingleSelectBox()

case( FORM  -> curField
                       
           ("X"
            "Y"                 
                 if X axlSingleSelectBox()  
                     else                  

                        Do something_2                               
               ); end if    

        ); end case

If I do this I can't check "Y" again in my FORM, because the operation axlSingleSelectBox() is active.To check the "Y" the operation must be canceled in first. Is there another way to do that? Could be proved if the boxes are checked, before the axlSingleSelectBox() wil be start?
Tahnks