code: def update(self, redraw=True):
          
          # get the main urwid.Frame widget
          mainframe = self.root_widget.original_widget
  
          # body
          if self.current_buffer:
              mainframe.set_body(self.current_buffer)
  
          # footer
          lines = []
          if self._notificationbar:  # .get_text()[0] != ' ':
              lines.append(self._notificationbar)
          if self._show_statusbar:
              lines.append(self.build_statusbar())
  
          if lines:
              mainframe.set_footer(urwid.Pile(lines))
          else:
              mainframe.set_footer(None)
          # force a screen redraw
          if self.mainloop.screen.started and redraw:
              self.mainloop.draw_screen()
docs: redraw interface