ALV fields which are not referenced to data dictionary table fields

Hello,

I am using function module reuse_alv_popup_to_select.

How do I display fields in ALV which are not referenced to

data dictionary table fields.

I am showing 4 columns in alv out of which first column is checkbox

and remaining 3 columns are from data dictionary and it works fine.

Now I need to add one more column which is of type checkbox.

I have added this field in my ITAB as flag(1) type C.

When I add this flag field in the field catalog, I get exception.

Regards,

Vishal.