Portal row conditional formatting based on existence of record in other table
I am building a class attendance tracking system that is destined for use on FMP Go on iPads.
I designed an attendance interface for a given class, that shows a full list of members in a portal (based on an X relationship between the class table and a separate instance of the member table).
The the user clicks on any row in the portal, a record is inserted in the Attendance table, with the relevant MemberID and ClassID. If The row is clicked again, the record is deleted.
That part works.
What I would like to do is format the row differently based on the existence of a record in the Attendance table that has a matching MemberID (to the row in the portal) and ClassID (to the Class in the Layout).