ZWINDOW CLASS.
       zWindow is a general class.  All classes in this group are 
 derived from it.
       The zWindow constructor taken from the zApp header file
has three parameters:
      - A pointer to a parent zWindow.
      - A pointer to zSizer
      - A style value.

       Here is the zWindow constructor:

zWindow(zWindow *, zSizer *, DWORD Stile);