Browse Prior Art Database

Generic View Handler Class

IP.com Disclosure Number: IPCOM000120877D
Original Publication Date: 1991-Jun-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 2 page(s) / 79K

Publishing Venue

IBM

Related People

Baker, R: AUTHOR [+3]

Abstract

The introduction of object-oriented programming technology into the current applications software products requires that standard sets of classes of objects be developed. Since software is typically developed to reside on many different hardware platforms, some generic classes must be developed which can abstract the hardware and windowing system dependencies from the actual software.

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This is the abbreviated version, containing approximately 52% of the total text.

Generic View Handler Class

      The introduction of object-oriented programming
technology into the current applications software products requires
that standard sets of classes of objects be developed. Since software
is typically developed to reside on many different hardware
platforms, some generic classes must be developed which can abstract
the hardware and windowing system dependencies from the actual
software.

      A generic class is provided which will facilitate platform
independence in object-oriented software systems and allow
considerable flexibility in developing windowing applications.  It
overcomes the current difficulties in writing applications for
multiple platforms and windowing systems by encapsulating the
window-specific behaviors of the objects within one generic class,
the ViewHandler class.

      The ViewHandler manages the views of an object in a system
where the models and views are in separate layers, such as the
Model-View- Controller scheme proposed by (*). The ViewHandler has
various parts, i.e., it is a composite object, composed of a window
for viewing its contents, a menu specific to its application, a list
of application- specific properties, an icon, and potentially other
parts as well, such as dialog boxes associated with the application.
Also the ViewHandler must hold some knowledge of the Model
(application) object associated with it and in the Model-View schema,
of the EventInterface objects established on its behalf.

      Each different type of object can have a ViewHandler that is a
subclass of the generic ViewHandler class.  The subclass will be an
application-specific ViewHandler with its own individual icons,
windows, etc.  For example, in an Office Desktop, the File Cabinet
object would h...