\chapter{Classes by category}\label{classesbycat} \setheader{{\it CHAPTER \thechapter}}{}{}{}{}{{\it CHAPTER \thechapter}}% \setfooter{\thepage}{}{}{}{}{\thepage}% A classification of Gizmos classes by category. \twocolwidtha{5cm} \begin{comment} {\large {\bf Service classes}} \overview{wxMPService class overview}{wxmpserviceoverview} Service classes reduce the diversity of PMF classes, by making them comply to a common interface. A service class serves as an interface (or mix-in class in C++ terms), which cannot itself represent an independent object. It should be inherited as a second (or third) base class. Derived services classes all derive from wxEvtHandler as well as wxPMService. \begin{twocollist}\itemsep=0pt \twocolitem{\helpref{wxPMService}{wxpmservice}}{Base class} \twocolitem{\helpref{wxPMBootstrapService}{wxpmbootstrapservice}}{Boot strap service} \twocolitem{\helpref{wxPMLAlgorithm}{wxpmlalgorithm}}{Layout algorithm service} \twocolitem{\helpref{wxPMSashLayoutAlgorithm}{wxpmsashlayoutalgorithm}}{Sash layout algorithm service} \twocolitem{\helpref{wxPMPane}{wxpmpane}}{Base class for panes lying outside the MDI client area} \end{twocollist} \end{comment}