The other option is to force Filemaker not to create a new portal row when I tab past the first record.
Tabbing past the first record should not create a new portal row. If "allow creation" is enabled, what looks like a blank new record will appear after the last real record in the portal, but no new record is actually created until data is entered into at least one field in the blank "add" portal row.
Nonetheless many solutions use a new portal record script instead of allow creation. You can find examples of this script in the starter solutions that come with FileMaker Pro.
Set Variable [$OrderID ; value: Orders::Order ID ] ---> this takes the place of a "copy" script step
Go to layout ["Units" (Units) ]
Set field [ Units::for_orderID ; $OrderID ] -----> takes the place of a "paste" script step
Go to Layout [Original Layout ]
One work of caution, the change in layouts can trip a great many script triggers on both the Orders and Units layouts. Sometimes these scripts have to be kept from doing anything in order for the above script to function correctly.
This works perfectly, and more importantly, I understand WHY it works. That allows me to solve other issues in the future. I can't thank you enough! Seriously, how do I buy you a beer?
Oh good, Im not a drinker and have no idea about beer. You've got mail.