This component is designed to be put in a panel with a flow layout, in the
southern part of a border layout, controlling a panel with a card layout in
the center part of the border layout. There are usage notes in the
first comment of the source code.
I put my break-out points within comments, to keep them with the
appropriate code. Here's the listing (available as
a text file, because the code is too
wide to be viewed in the web page):
