Ahh .. I know exactly what your trying to achieve now. I was testing in B4J , thats why I did not see the .Prompt method.
I have had the same issue and are in the process of designing my own custom combo box.
In actual fact my first Item was blank " " because I did not want a Prompt text .
This might shed some light on the cmbBox (Spinner) .Prompt issue.
Hello forums. There seems to be a problem in my spinners. When i click spinners, it doesn't show its prompt name. But i placed First Name on the properties menu. Is there any other way to show the prompt name when i run my app? Thanks Love Horage
As far as I know , there is no actual event to detect if the combo list has been clicked (expanded) to give you and opportunity to delete you prompt text ..
And you would then have to manually re-add the prompt text again.
Maybe
@Erel could shed some thoughts / solution.