Returns the column index where a dropped item should be placed in the
table. Interpretation of the value depends on the return of
isInsertColumn()
. If that method returns
true
this value indicates the index where a new
column should be inserted. Otherwise, it represents the value
of an existing column on which the data was dropped. This index is
in terms of the view.
-1
indicates that the drop occurred over empty space,
and no column could be calculated.
Returns:
the drop row