使用 schemaextender 扩展 ATEvent 类

Question

我使用 schemaextender 来扩展 ATEvents，以便它们包含一个用于切换事件时间和 iCal 显示的复选框。

它在现有网站上工作正常，但当我尝试创建一个新网站时，我收到错误“ValueError：nextPreviousEnabled.default_method既不是方法，也不是可调用的方法”

有什么想法吗？扩展代码：

from Products.Archetypes.public import BooleanField
from archetypes.schemaextender.field import ExtensionField

class DisplayEventTimeField(ExtensionField, BooleanField):
    """A toggle to indicate whether the view should display the time or just the date of this community event"""

from zope.component import adapts
from zope.interface import implements
from archetypes.schemaextender.interfaces import ISchemaExtender
from Products.Archetypes.public import BooleanWidget
from Products.ATContentTypes.interface import IATEvent

class EventExtender(object):
    adapts(IATEvent)
    implements(ISchemaExtender)


    fields = [
        DisplayEventTimeField("display_event_time",
        widget = BooleanWidget(
            label="Display event time",
            description="Turn this off to show only the event date (also disables iCal/vCal)",
            defult=True)),
            ]

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

    def getFields(self):
        return self.fields

和完整的回溯：

Traceback (innermost last):
  Module ZPublisher.Publish, line 127, in publish
  Module ZPublisher.mapply, line 77, in mapply
  Module Products.PDBDebugMode.runcall, line 70, in pdb_runcall
  Module ZPublisher.Publish, line 47, in call_object
  Module Products.CMFPlone.browser.admin, line 201, in __call__
  Module Products.CMFPlone.factory, line 83, in addPloneSite
  Module Products.GenericSetup.tool, line 330, in runAllImportStepsFromProfile
   - __traceback_info__: profile-Products.CMFPlone:plone-content
  Module Products.GenericSetup.tool, line 1085, in _runImportStepsFromContext
  Module Products.GenericSetup.tool, line 999, in _doRunImportStep
   - __traceback_info__: plone-content
  Module Products.CMFPlone.setuphandlers, line 486, in importContent
  Module Products.CMFPlone.setuphandlers, line 234, in setupPortalContent
  Module Products.CMFPlone.utils, line 306, in _createObjectByType
  Module Products.CMFCore.TypesTool, line 554, in _constructInstance
  Module Products.ATContentTypes.content.topic, line 6, in addATTopic
  Module Products.Archetypes.BaseFolder, line 96, in manage_afterAdd
  Module Products.Archetypes.BaseObject, line 159, in manage_afterAdd
   - __traceback_info__: (<ATTopic at /Plone/news/aggregator>, <ATTopic at /Plone/news/aggregator>, <App.ProductContext.__FactoryDispatcher__ object at 0x1071bfd50>)
  Module Products.Archetypes.BaseObject, line 174, in initializeLayers
  Module Products.Archetypes.Schema, line 338, in initializeLayers
  Module Products.Archetypes.Storage, line 161, in initializeField
  Module Products.Archetypes.Field, line 591, in getDefault
ValueError: nextPreviousEnabled.default_method is neither a method of <class 'Products.ATContentTypes.content.topic.ATTopic'> nor a callable

Answer 1

尝试使用 browserlayer 并实现 IBrowserLayerAwareExtender< /code> 而不是 ISchemaExtender：

...
from archetypes.schemaextender.interfaces import IBrowserLayerAwareExtender
from my.product.browser.interfaces.IMyProductLayer

class EventExtender(object):
    adapts(IATEvent)
    implements(IBrowserLayerAwareExtender)
    layer = IMyProductLayer
    ...

这可确保仅在安装产品时才扩展架构。一般来说，始终建议保持自定义与实际克隆实例的隔离。