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XView Internals
This chapter discusses the internal mechanisms that XView uses to implement the existing
object classes. The information in this chapter should give you the ability to build your own
objects that are “extensible” or are extensions of other existing classes. By writing exten-
sions to XView classes, you can modify their appearance or functionality. By creating new
classes, you can create objects that go beyond what the existing XView library provides.
However, you should be forewarned that building XView extensions is not intended to be a
solution to every problem. You are strongly encouraged to implement the type of object or
enhancements you need using the facilities provided by XView and the existing XView
objects. Furthermore, this chapter should be used as an introductory resource. It does not
contain enough information to fully explain how all the internal XView objects work, nor
does it give you the ability to build an entire library of user interface objects.
If OPEN LOOK compliance is important in your applications, you should be sure that you
fully understand the OPEN LOOK specifications before attempting to build new objects or
modify existing ones. Because the XView internals do not enforce user interface policy, you
could build non-OPEN LOOK-compliant user interface code. However, the existing XView
objects were written to conform to OPEN LOOK as much as possible. ...