To test the new Close
Window Button, delete the existing Close Window button on the Display_data
frame, and then add the new Close Window Button to the frame. Because
you set all the attributes on the Close Window Button subclass, the
button will work without any additional configuration (although you
will have to redefine the attachments to the Close Window Button).
If you want to change
something about the Close Window Button, in most cases you only have
to make a change to the class, and the change is propagated to all
the instances of the Close Window Button in all frames that use it.
A complete discussion
of object-oriented development is beyond the scope of this appendix,
but creating this simple subclass demonstrates how useful subclassing
can be. For more information about object-oriented development in
SAS/AF, see the
Guide
to SAS/AF Applications Development.