[Thuban-devel] Re: RfD: Support for layer specific resources

[Martin Schulze]

Moin!

Bernhard Herzog wrote:
> > Bernhard Herzog wrote:
> >> No, I'm not sure, and I don't have the time to find the perfect place
> >> for it.  You didn't want it in Thuban.UI.classifier, though, and that
> >
> > No, I wasn't sure how I am supposed to implement this in
> > classifier.py. 
> 
> Just as you would in the wms extension.

Exactly.

> [...]
> > Proposal:
> >
> >     Add Thuban/UI/propdialgs.py (or any other name) with (as stated in
> >     the July 27th mail):
> >
> >     a) the declaration of the global variable
> >
> >     b) the global register function
> >
> >     c) the access function to make it complete [optional]
> >
> >        Since in practice only mainwindow needs to look up the mapping,
> >        this isn't required and can be done directly in mainwindow as
> >        well, but it would break the modular concept a bit.
> >
> > Would that be acceptable for you?
> 
> I'd at least omit the accessor functions in b) and c).  It's fine to
> call methods on the ClassMapper instance directly.  The variable name of
> the instance shouldn't start with _ then, though.

Ok.  That works.  It's basically a two-line module, but... well... it
works at least and is a more or less clean design.

> Introducing a new module which effectively contains only one object
> seems wasteful.  OTOH it is a bit more modular than putting it into the
> mainwindow module, but then again, even that is much more modular than
> what we have now.  I'd probably just stick the ClassMapper instance into
> mainwindow for now and create a new module if we really need it some
> day.  It wouldn't be hard to maintain a backwards compatible interface
> for a while either.

Having it in mainwindow doesn't work since that would introduce a
circular import chain.  mainwindow is already importing the classifier,
so the classifier cannot import the mainwindow.  Hence, this needs to
be dragged out into a different module.

> However, I have spent practically 100% of my time on non-Thuban things
> for the last several months and that won't change anytime soon.  I don't
> really have time to make up my mind about this or to keep discussing
> this much longer.  I'd say, you decide which way to go here and just
> check that in.  I'm sure you'll come up with a reasonable solution.

Thanks.

I'm attaching the solution in a patch to this mail, in case you or
anybody else still wants to comment on it.  If not, I'll commit it
on Friday.

Regards,

	Joey

-- 
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