From Xojo Documentation
| This item has been deprecated since version 2018r4 and should no longer be used.
There is no replacement for this item.
Property (As String )
Name of a field in the database table referenced by DataControl.
Relevant only if the ListBox is used in conjunction with a DataControl to display the contents of fields in a database table.
This example specifies the field for the ListBox.
Me.DataField = "FirstName"