[Zope3-Users] Multiple containers in one object - how to implement in Zope3?

[Alek Kowalczyk]

Hello,

I have a simple (on the first sight) problem, which I don't know how to
resolve in zope3'ish way.

I have a single object, which can contain many objects of 2 another
types (IType1, IType2). My intention is to have those objects contained
in separate collections (because they are very different 2 types of
objects and should not be mixed in one collection)
I'd like to have each collection editable like Zope folder, i.e each
collection to be IContainer/BTreeContainer.

I tried to use the following pattern (which would be natural for pure
python or C++ - i.e. two "Dict"s or two "std::map<string,Type1/2>" objects):

class IMasterObject(Interface):
    objects1 = Object(schema=IObjects1, title=u"Objects of IType1")
    objects2 = Object(schema=IObjects2, title=u"Objects of IType2")

class IObjects1(IContainer):
    pass
    # + constraint to have only objects implementing IType1

class IObjects2(IContainer):
    pass
    # + constraint to have only objects implementing IType2

I have implemented a simple view and created proper ObjectWidgets - no
bigger problems there.
But web interface, after creating MasterObject, shows only empty
fieldset for objects1 and objects2 fields in MasterObject instance. I
don't know how to achieve displaying "Container" view in those fieldsets
instead of "Edit" view.

I have the following questions:
- Is this the proper way to implement an object containing two different
containers/collections of objects and still use 'folder-like' web
interfaces for adding/removing/viewing those collections?
    - If yes, how to display "Container" view in those fieldsets instead
of "Edit" view?
    - If not, how would you suggest to implement this pattern (or its
functional equivalent) in Zope3?

It seems to be pretty common pattern but I couldn't find a solution
anywhere in the book or on the net, so I suspect I was looking for wrong
solution and this should be realized in very another way in Zope3...

Best regards,
Alek Kowalczyk.