ATContentTypes

Description

Since Plone 2.1, Plone has shipped with ATContentTypes for its default content types

“ATContentTypes”:/products/atcontenttypes is a re-implementation of the standard CMF types as Archetypes content. It adds a numer of features to the standard CMF types and offers more flexibility in extending and re-using content types. The “RichDocument tutorial”:/documentation/tutorial/richdocument explains how ATContentTypes are subclassed and how they make use of the latest conventions in Archetypes and CMF. The ATContentTypes product is installed during the creation of a Plone site. It will migrate the base CMF content types to its own equivalents using its own highly generic migration framework. Please note that ATContentTypes aims to be usable in plain CMF. It has a number of optional Plone dependencies, in the form:

if HAS_PLONE21:
…
else:
…

Plone has no direct dependencies on ATContentTypes, nor on Archetypes. There are a few generic interfaces in ‘CMFPlone.interfaces’ that are used by both Archetypes/ATContentTypes and Plone, but we do not wish to have any direct dependency on Archetypes, since Archetypes is essentially just a development framework to make developing CMF content types easier. By minimising the number of dependencies, we ensure that plain-CMF (and in the future, plain-Zope 3) content types are still usable within Plone. ATContentTypes and Plone both depend on ‘CMFDynamicViewFTI’. This is a wrapper on the standard CMF FTI type that adds support for the ‘display’ menu by recording a few extra properties for the available and currently-selected view methods. It also provides a mixin class, ‘CMFDynamicViewFTI.browserdefault.BrowserDefaultMixin’, which enables support for the ‘display’ menu (or rather, the interface ‘CMFDynamicViewFTI.interfaces.ISelectableBrowserDefault’).