I have been unable to determine where and how to enable/disable push buttons on a screen.

I have a program which has:
DO myscreen.spr

On the screen myscreen several push buttons need to be enabled depending upon whether some records exist.

I've tried this code:
SELECT TCursor
IF RECCOUNT() > 0
SHOW GET mButton ENABLE
ENDIF

in several places including,
before the DO myscreen.spr
after the DO myscreen.spr

in myscreen.spr Seup snippet,

but none works.

Kim