[Zope-dev] ZPatterns.. Property sheets... once and for all. ;-)

[Steve Spicklemire]

Hi Folks,

   OK.. I didn't hear much from my last plea for advice... I 
thought perhaps such a concrete problem would product lots
of sage advice... but there's good news: here's another chance!

Really Really Basic:

If I have a class like so:

class Shopper(
    OFS.SimpleItem.Item,
    ZPatterns.DataSkins.DataSkin,
    Acquisition.Implicit,
    AccessControl.Role.RoleManager,
    ):

    """ A Shopper """

    # Specify a name for the item type:
    meta_type='Shopper'

and let's say I define some attributes in the class.... 

    id = 'default'
    email = ''
    _passwd = ''

Now... let's further say that I want a developer using this class to
be able to add propertysheets to instances of this class after I'm
finished... to make customized versions of these
objects. Also.. perhaps I want to take advantage of the 'automatic'
nature of property sheets to provide a usable interface so that users
can edit various properties. I was successful in adding a propertysheet
using the 

/specialist/anobject/propertysheets/manage_addPropertySheet?id=foo&ns=

technique.. which I'm pretty sure I could also implement 
programattically. ;-). But when I try:


/specialist/anobject/propertysheets/foo/manage

I get an attribute error looking for 'a_'. 

I get the same error when I try:

/specialist/anobject/propertysheets/foo/manage_addProperty?id=blah&value=hh&type=string

Any idea what's up with that?

But no matter... I can't add 'email' to *any* propertysheet, even those
in the ZClass, since it's already used in the class. So do I leave it out
of the class and "hope" that someone defines it in some propertysheet
somewhere? Do I do lots of:

if hassattr(self, 'email') and so on.. in case somehow it didn't get taken
care of? I *know* I missing something deep. I'm sure I'll say something
dumb enough here soon.. and someone will point out my basic misunderstanding. ;-)

thanks!
-steve