webvbt/src/HTMLVBT.i3

 Copyright (C) 1995, Digital Equipment Corporation                         
 All rights reserved.                                                      
 See the file COPYRIGHT for a full description.                            
                                                                           
 Last modified on Thu Sep 28 16:07:39 PDT 1995 by mhb                      

<* PRAGMA LL *>

 An HTMLVBT is an abstract VBT class for displaying HTML. Subclasses
   override the methods here (in particular, the init method) with
   procedures that do something interesting. 


INTERFACE HTMLVBT;

IMPORT Filter, HTML, Point, VBT;

TYPE
  T <: Public;
  Public =
    Filter.T OBJECT
    METHODS
      <* LL <= VBT.mu *>
      init (html: HTML.T): T;

      <* LL = VBT.mu *>
      hotlink (url: TEXT; READONLY cd: VBT.MouseRec);
      ismap   (url: TEXT; READONLY pt: Point.T; READONLY cd: VBT.MouseRec);
      isindex (typein: TEXT);
      form    ();
    END;

 The call v.init(...) initialize v to be an HTMLVBT.T displaying
   the HTML given by html.  The default method initializes v as a
   Filter.T.


   The method v.hotlink(url,cd) is called when the user has clicked on a
   link.  The default is a noop.


   The method v.ismap(url,pt,cd) is called when the user has clicked on
   an active map.  The default is a noop.


   The method v.isindex(typein) is called when the user has entered a
   carriage return in the typein field of some html that contains an
   ISINDEX tag.  The default is a noop. 


END HTMLVBT.





interface HTML is in: