[Zope] Defining meta_types

[Jesper Holmberg]

Hi all,

I've created a Product Step which is a subclass of Folder. I want restrict
what types of objects I can put in an object of type Step.

The "Developer's guide" has this to say on the subject:

"If you wish to control which types of objects can be contained by
instances of your product you can set the meta_types class attribute. This
attribute should be a tuple of meta_types."

I naively interpreted this such that I could put this in my class:

meta_types = ('Step', 'SURef',)

But this gives me the errors:

Error Type: AttributeError
Error Value: has_key

With the backtrace:

File /usr/lib/zope/lib/python/OFS/ObjectManager.py, line 271, in filtered_meta_types
    (Object: Step)

So I found a tip on the Web, saying I could do this:

meta_types = ({'name':'Step', 'action':'manage_addStepForm'},)

Now, this doesn't give me an error, but the effect is that I get one more
Step as alternative on the drop-down menu "Select type to add..."
*in addition* to all the alternatives. But I wanted to restrict the
possibilities, not augment them.

What am I doing wrong?

TIA

Jesper


-- 
          Jesper Holmberg            |"But how can |
  jesper.holmberg@enst-bretagne.fr   | one be warm |
ENST Br, BP 832, 29285 Brest, FRANCE | alone?"     |