When you set this attribute, the assigned widget is moved to the last tab position, following the widget that was previously at this position. Other widgets in the field group maintain their same relative tab positions.
To set the attribute, you must assign it the handle of a field-level widget or frame that can receive focus from a TAB event and that is also a child of the field group to which the attribute applies. If the LAST-TAB-ITEM attribute is not set (is the Unknown value (?)), the default last tab position goes to the widget identified by the LAST-CHILD attribute of the field group.
For more information on how frames owned by a field group participate in the tab order of that field group, see the
FRAME widget reference entry.