3. The Data Structures

Now that you have a passingly familiar with the basics, let's digress for a time and take a look at the data structures involved in the GeoUtils, as they should be understood before we talk about the implementation of an example subclass. There are three different data structures tangled up in the GeoUtils layout mechanism (figure ): the XmGeoMatrix controls how the layout is to be performed, the XmGeoMajorLayout contains information about individual rows or columns of childen, and finally the XmKidGeometry records the geometry of a single child.

Figure: Layout structures to mess around with when using the GeoUtils.