Hi guys
I got two forms:
1 SalesOrder Header form
2 SalesOrderLines Form
The procedure is this, after the Planning Completed Date Field saved in SalesOrder Header form, then this field becomes display only in the SalesOrderLines form.

I can only figure out how to make a field become display only in which the way of setting the attr.input to false, but I do not know how to detect save action first then change to display only second

Any suggestion would be helpful

thanks

Look up the main.table.io sections or maybe choice.update.db. When they hit the save button you can set a variable to true. Then you could do if variable then lattr.input is false. Just remember if they do a new record or some other action you would probably want to set the variable back to true.