APEX

I'm trying to implement conditional branching and it's not working. I have 2 radio buttons (Summary and Detail) that are based on a LOV (Summary="Y", Detail="N"). I want the user to be able to click on a button (Make Report) and be redirected to the appropriate page.

My button submits "DISPLAY". I have 2 conditional branching set to occur after DISPLAY has been submited (after computation, validation and processing). The condition type is "Value of Item in Expression 1 = Expression 2".

Expression 1 = P4_OPT_REPRT
Expression 2 = "Y"

I've tried variations, such as :P4_OPT_REPRT, &P4_OPT_REPRT and it doesn't work. What am I doing wrong?

I've seen several threads on this forum on this topic, but none of them solved my basic problem. So I'm guessing that whatever I'm doing wrong, is some kind of noob trap.