Implement F4 Value-Request Functionality in Dialog Programming

Hi. Apologies in advance if this is the wrong forum.

I'm on R/3 4.6c.

What is the best way to implement this:

AT SELECTION-SCREEN ON VALUE-REQUEST FOR xxxx-low.

in a dialog program?

I have my selection screen defined in my TOP include, but since dialog programs don't support report events I am not sure what to do.

Thank you for any assistance you could provide.

Best Regards,

Brett