This is what victory looks like! FlattenerFilterDialog

This is what victory looks like!  FlattenerFilterDialog

Heh, ok, it's not total victory.

FlattenerFilterDialog works (it's a small subclass of
PCrudFilterDialog), and it  cooperates with FlattenerGrid.  That's the
good news.  But the way it works is sometimes less than ideal due to
design under-think.

Imagine core class acp, and you have a map for the flattener with these
columns, because these are the things you want to see in the grid:

{
    "barcode": "barcode",
    "shelving_loc": "location.name",
    "shelving_loc_owning_lib": "location.owning_lib.shortname"
}

The FlattenerFilterDialog figures out the terminal fields for each of
those paths, which are acp.barcode, acpl.name, and aou.shortname.  It
naturally gives you the appropriate AutoWidget for each of those things.

Which is a TextBox. In every case.

Because all of those are text field.

See the problem?

They do /work/, but as a user you probably want to get an org unit
dropdown instead of being expected to type "BR1" or "ARL-ATH" or
whatever.

So I guess the way to make this better is to give an option in the
FlattenerGrid per-column (which will pass this option onto
FlattenerFilterDialog) that tells us how many steps /from/ the end to
stop when we're looking for a field to inform our choice of AutoWidget?
So instead of [acp.]location.owning_lib.shortname = aou.shortname, if we
stop at one step from the end we get acpl.owning_lib instead, which
would give us a much more appropriate autowidget.

yeah.

that'll be the solution

Also, as a bonus, you can now leave out the header name between <th> and
</th>, and it will be filled in from the IDL.  This is surprisingly
often not what you really want, but it's a better reasonable default
than the raw field name.

Signed-off-by: Lebbeous Fogle-Weekley <lebbeous@esilibrary.com>