##############################################################################
#
# Copyright (c) 2006 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""
"""
__docformat__ = "reStructuredText"
import zope.schema
import zope.schema.interfaces
from z3c.schema.i18n import MessageFactory as _
[docs]class IOptionalChoice(zope.schema.interfaces.IChoice,
zope.schema.interfaces.IFromUnicode):
"""Optional Choice
This field can either represent a choice or a textline value.
Validation proceeds as follows:
1. Check whether the value is one of the choices. If so, return
successfully.
2. If no choice match was found, validate the value against the
``value_type`` field.
The conversion from unicode values proceeds in a similar fashion:
1. Try to match the unicode value to a token in the vocabulary.
2. If no match was made, call the unicode conversion method of the
``value_type`` field.
"""
value_type = zope.schema.Field(
title=_("Value Type"),
description=_(u"The freely entered values must be of this type."),
required=True)