I have a dialog that uses QDataWidgetMapper to map a number of database fields to (among other things) some Combo Boxes. One combo box holds a list of students. A button on the dialog launches another dialog that allows the user to add another student into the database. When this dialog is closed, if a student was added, I want the combo box to update (so that it displays the new student that was just added) and automatically select the newly inserted student.

I have tried many approaches to getting the combo box to update, including:
- running select on the QSqlRelationalTableModel that the mapper uses
- disabling the combo box while the "add student" dialog is visible and re-enabling it when the student dialog closes
- unmapping and remapping the combo box to the mapper

None of these approaches seem to work.

I know I am missing something simple, but this time I just can't seem to figure out what it is. Any suggestions?