-- File:	TPrsStd_Driver.cdl
-- Created:	Fri Aug  1 10:44:29 1997
-- Author:	SMO
---Copyright:	 Matra Datavision 1997

deferred class Driver from TPrsStd inherits TShared from MMgt

    --- Purpose: Driver for AIS
    --           ==============
-- An abstract class, which - in classes inheriting
-- from it - allows you to update an
--  AIS_InteractiveObject or create one if one does
--  not already exist.
--  For both creation and update, the interactive
--  object is filled with information contained in
--  attributes. These attributes are those found on
 -- the label given as an argument in the method Update.
-- true is returned if the interactive object was modified by the update.
    --  This class  provide  an algorithm  to  Build with its  default
    --  values (if Null) or Update (if !Null) an AIS_InteractiveObject
    --  .   Resources are found  in  attributes associated to  a given
    --  label.

    --  The algorithm Returns   <True>  if the minimum  resources  are
    --   found.  The  returned AIS may   be null  if  algorithm failed
    --  (values of resources attributes are not acceptable).

    --  This  algorithm may   be  called, even if  an AISPresentation
    --  attribute  is not setted at  the label (for simulation need by
    --  example).

    --  It belongs to the application to test the returned AIS object,
    --  to set  it in  the AISPresentation  attribute and to  set  the
    --  owner of the AIS. See Tool class for default implementation of
    --  those methods.

uses Label             from TDF,
     InteractiveObject from AIS


is

    Initialize;
    
    Update (me : mutable ; L   :        Label from TDF;
	                   ais : in out InteractiveObject from AIS)
---Purpose:
-- Updates the interactive object ais with
-- information found on the attributes associated with the label L.
        returns Boolean from Standard
    is  deferred;    
    

end Driver;