14.50 SelectionPicture Interface

14.51 SelectionPicture

ORIGIN 'Bifrost';
BODY 'private/Impl/SelectionPictureImpl';

(*
 * COPYRIGHT
 *       Copyright Mjolner Informatics, 1990-94
 *       All rights reserved.
 *)

-- BifrostAttributes: attributes --

SelectionPicture: Picture
  (* A picture used to hilite a group of graphical objects.
   * SelectionPicture automatically highlights the graphical objects
   * added to it.
   *)
  (# thecanvas: ^Canvas
       (* The Canvas the GOs are shown in *);
     init::< (# enter theCanvas[] ... #);
     copy::<
       (# do ... #);
     draw::< 
       (# ... #);
     erase::< 
       (# ... #);
     add::< 
       (# ... #);
     delete::< 
       (# ... #);
     clear: 
       (* Remove all graphical objects from THIS(SelectionPicture) *)
       (# ... #);
     onOneGO:< object
       (* Called when noOfGOs becomes 1 *);
     onTwoGOs:< object
       (* Called when noOfGOs changes from 1 to 2 *);
     onEmpty:< object
       (* Called when noOfGOs becomes 0 *);
  #)