I searched the forum but wasn't able to find an answer.
I am trying to clear the current selection in a combo box:
this.getField("COMBOBOXNAME").value = '';
This isn't working though and the debugger returns an error of "InvalidSetError: Set not possible, invalid or unknown." It seems pretty clear that I'm either setting an incorrect property for a combo box or setting the right property to an incorrect value. I don't want to change the options available, just clear out what is currently displayed.
Read the reference of the currentValueIndices property of the Field object.
Thanks for the direction!
I ended up doing the following based on information from the property you mentioned. Change the field to editable, set the value to "", set the editable property back to false.