Parameterised dynamic vocabulary. Shows unique values for catalog index. Pass in the index name in the schema.

gistfile1.py

Definition:
===========
 
from zope.schema.interfaces import IContextSourceBinder, IBaseVocabulary

class CatalogIndexValuesSource(object):
    grok.implements(IContextSourceBinder, IBaseVocabulary)

    def __init__(self, index_name):
        self.index_name = index_name

    def __call__(self, context):
        catalog = getToolByName(context, 'portal_catalog')
        if self.index_name not in catalog.indexes():
            return SimpleVocabulary([])
        terms = [SimpleVocabulary.createTerm(x, x, x) for x in catalog.uniqueValuesFor(self.index_name)]
        return SimpleVocabulary(terms)

Usage:
======
class ITableRowFilter(form.Schema):
    title = schema.Choice(
        title=u'VHE Nummer',
        vocabulary=CatalogIndexValuesSource('getId'),
        required=False)