$Id: Component_Heirarchy.txt,v 1.10 1998/04/16 16:21:11 sfarrell Exp $

This is the inheretence heirarchy for classes in the tablelayout
manager.  Widgets can generally be derived from anything from
Component down.  The bracketed stuff is new methods introduced, the
curly-braced stuff is instance data.  The stuff with *'s you'll
probably need to override (this is not a hard & fast rule--you may not
need to, and you many need to override others.)

The deal with the "tl" prefix is that it appears iff the method (a) IS
part of the baseclass (b) it is NOT external.  The idea is that if we
can avoid obvious name collisions this is a good thing, as long as we
don't make an obfuscated external interface (which is a bad thing).

                        TL_BASE  [ _isa(), new()*, tl_getParameters(),
                           |       delete(), setParams(),
                           |       tl_inheritParamsFrom(), 
                           |       tl_getLocalParameters() ] 
                           |     { "TL_PARAMS", "TL_PARAMS_ISA" }
                           |
                           |
                           |
                        Component [ tl_setContext(), tl_getContainer(),
                           |        tl_getWindow(), tl_getForm(), 
                           |        tl_setup()*, tl_print()*
                           |        tl_breakAfter() ]
                           |      { "TL_CONTAINER", "TL_WINDOW", "TL_FORM" }
                           |
                           |
               +-----------+-------------------------+
               |                                     |
               |                                     |
       ComponentContainer                            |
   [ insert()*, insertLn()* ]                        |
   { "TL_COMPONENTS" }                               |
               |                                     |
               |                                     |
               |                                     | 
      +--------+-------+                         FormComponent 
      |                |                     [ tl_getName(), tl_setName(),
      |                |                       tl_getValue(), tl_setValue(),
      |                |                       tl_setDefaultValue() ]
ComponentTable      ComponentCell            { "TL_PARAMS"->"name",
                                               "TL_PARAMS"->"value" }
                                              (overrides tl_create())
                                                     |
                                                     |
                                              FormComponentMulti 
                                             { "TL_DEFAULT_VALUE"
                                               "TL_OPS" }
                                             (overrides tl_setDefaultValue())