needs-update

   

Called by the snip to request that the snip's display needs to be updated. The administrator determines when to actually update the snip; the snip's drawmethod is eventually called.

• (send a-wx:snip-admin needs-update snip localx localy w h) -> void
      snip :  wx:snip% object
      localx : inexact real
      localy : inexact real
      w : inexact real
      h : inexact real

  The localx, localy, w, and h arguments specify a region of the snip to be refreshed (in snip coordinates).