public int locationToIndex (Point location)

Returns the cell index closest to the given location in the list's coordinate system. To determine if the cell actually contains the specified location, compare the point against the cell's bounds, as provided by getCellBounds. This method returns -1 if the model is empty

This is a cover method that delegates to the method of the same name in the list's ListUI. It returns -1 if the list has no ListUI.

location    the coordinates of the point

Returns:  the cell index closest to the given location, or -1