'vspace: how much vertical space to keep clear'

def __init__(self, master, name, vals, vspace):

    (cols, rows) = master.ui.get_cols_rows()
    self.ge = grideditor.OptionsEditor(master, name, vals)
    super().__init__(urwid.AttrWrap(urwid.LineBox(urwid.BoxAdapter(self.ge, (rows - vspace)), title=name), 'background'))
    self.width = math.ceil((cols * 0.8))
