# File locana/l_datebox.rb, line 411
   def on_up_key(levent=nil, &block)
      return bind(:on_up_key, block) if (block)  # this necessary to support Blocks the same as Proc objects

      val = 1
      if (levent[:shift_key])
         add_seconds(val * 60*60)  if (include_time?) # add/sub 1 hour

      elsif (levent[:ctrl_key])
         add_seconds(val * 60) if (include_time?)     # add/sub 1 min

      elsif (levent[:alt_key])
         open_calendar()
      elsif (levent[:meta_key])
         add_seconds(val) if (include_time?)          # add/sub 1 sec

      else
         add_seconds(val * 60*60*24)                  # add/sub 1 day

      end
   end