where to write the 'CHECK' event in SCENARIO_PROCESS_USER_COMMAND

Hi,

I am using ISR form to customize the rendering. I wasn't able to capture the event "CHECK" whenever the user clicks the Review button. I am using the code on the Listbox using java script:

if($record.CONTROL_PARAM.ISR_EVENT = "CHECK")

then

this.access = "readonly"

else

this.access = ""

endif

How to make sure on the BADI side that CHECK event is triggered. What code and where do I need to write relevant code so that my javascript will work. Do I need to write a customized version of SCENARIO_PROCESS_USER_COMMAND or directly write in SCENARIO_PROCESS_USER_COMMAND.

Thanks and Regards.