XHTML Role Attribute Module

The XHTML Role Attribute defined in this specification allows the author to annotate XML Languages with machine-extractable semantic information about the purpose of an element. Use cases include accessibility, device adaptation, server-side processing, and complex data description. This attribute can be integrated into any markup language based upon XHTML Modularization [XHTMLMOD].

Status of This Document

This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at http://www.w3.org/TR/.

This document is the second Public Working Draft, and is nearly complete. It is based upon comments received against the previous draft, and also upon work done in the definition of [XHTML2], and is therefore relatively mature.

Publication as a Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

1.Introduction

This document is a module designed to be used to help extend the scope of XHTML-family markup languages into new environments. It has been developed in conjunction with the accessibility community and other groups to make it easier to describe the semantic meaning of XHTML-family document content.

2.Conformance Requirements

The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].

Note that all examples in this document are informative, and are not meant to be interpreted as normative requirements.

2.1.Document Conformance

XHTML Role Attribute Module is not a stand-alone document type. It is intended to be integrated into other host languages such as XHTML. A conforming XHTML Role Attribute Module document is a document that requires only the facilities described as mandatory in this specification and the facilities described as mandatory in its host language. Such a document must meet all the following criteria:

2.2.Host Language Conformance

When the XHTML Role Attribute Module is included in a host language, all of the facilities required in this specification MUST be included in the host language. In addition, the attribute defined in this specification MUST be included in the content model of the host language. Finally, the attribute MUST be referenced using its namespace-qualified form (e.g., <myml:myelement xhtml:role='definition'>a term</myml:myelement>).

2.3.User Agent Conformance

A conforming user agent MUST support all of the features required in this specification.

3.The XHTML Role Attribute

The role attribute takes as its value one or more white-space separated QNames. Any non-qualified value MUST be interpreted in the XHTML namespace, and MUST be taken from the list defined in this section.

The attribute describes the role(s) the current element plays in the context of the document. This can be used, for example, by applications and assistive technologies to determine the purpose of an element. This could allow a user to make informed decisions on which actions may be taken on an element and activate the selected action in a device independent way. It could also be used as a mechanism for annotating portions of a document in a domain specific way (e.g., a legal term taxonomy).

This example is informative

<ul role="navigation wai:sitemap">
    <li href="downloads">Downloads</li>
    <li href="docs">Documentation</li>
    <li href="news">News</li>
</ul>

Authors may use the following standard oles, listed here with f their conventional interpretations. They are intended to define regions of the document to help orient the user.

3.1.Extending the collection of roles

It is possible to define additional role values. Such values MUST be defined in their own namespace. Note that current best practice is that the URI associated with that namespace resolve to a resource that allows for the discovery of the definition of the roles in the namespace. Example definitions include the RDF Schema for the XHTML role attribute values in Appendix B, and the Web Accessibility Initiative's work on an RDF Taxonomy [WAIRDF].

A.DTD Implementation

The DTD implementation of XHTML Role Attribute Module conforms to the requirements defined in [XHTMLMOD]. Consequently, it provides a Qualified Names sub-module, and a module file for the XHTML Role Attribute Module module defined in this Proposed Recommendation.

A.1.Qualified Names Module

Note that this module defines the parameter entity %xhtml-role-attrs.qname;. This entity is intended to be used in the attribute lists of elements in any host language that permits the use of the role attribute on elements in its own namespace. In this case the Host Language driver should set a parameter entity %XHTML-ROLE.prefixed; to INCLUDE and a parameter entity %XHTML-ROLE.prefix; to a value that is the prefix for the XHTML Role Attribute Module attributes.

A.2.XHTML Role Attribute Module

B.RDF Schema

This section will contain an example RDF specification for the roles that are defined in this document.

This example is informative

<?xml version="1.0"?>
<!DOCTYPE rdf:RDF [
    <!ENTITY xsd "http://www.w3.org/2001/XMLSchema#">
    <!ENTITY dc "http://dublincore.org/2003/03/24/dces#">
    <!ENTITY owl "http://www.w3.org/2002/07/owl#">
    <!ENTITY rdfs "http://www.w3.org/2000/01/rdf-schema#">
    <!ENTITY rdf "http://www.w3.org/1999/02/22-rdf-syntax-ns#">
    <!ENTITY states "http://www.w3.org/2005/07/aaa#">
    <!ENTITY skos "http://www.w3.org/2004/02/skos/core#">
    <!ENTITY wairole "http://www.w3.org/2005/01/wai-rdf/GUIRoleTaxonomy#">
]>
<rdf:RDF xml:base="http://www.w3.org/1999/xhtml" xmlns:dc="http://purl.org/dc/elements/1.1/#" xmlns:owl="http://www.w3.org/2002/07/owl#" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#" xmlns:skos="http://www.w3.org/2004/02/skos/core#" xmlns:states="http://www.w3.org/2005/07/aaa#" xmlns:wairole="http://www.w3.org/2005/01/wai-rdf/GUIRoleTaxonomy#" xmlns:xhtml="http://www.w3.org/1999/xhtml#">
    <owl:Class rdf:ID="banner">
        <rdfs:subClassOf rdf:resource="wairole:region"/>
        <wairole:scope rdf:resource="wairole:document"/>
        <dc:description xml:lang="en">A banner is usually defined as the 
      advertisement at the top of a web page. The banner content typically 
      contains the site or company logo and other key advertisements for the site.
      </dc:description>
    </owl:Class>
    <owl:Class rdf:ID="contentinfo">
        <rdfs:subClassOf rdf:resource="wairole:region"/>
        <wairole:scope rdf:resource="wairole:document"/>
        <dc:description xml:lang="en">This is information about 
      the content on the page. For example, footnotes, copyrights, links to privacy 
      statements, etc. would belong here.
      </dc:description>
    </owl:Class>
    <owl:Class rdf:ID="definition">
        <rdfs:subClassOf rdf:resource="wairole:section"/>
        <wairole:scope rdf:resource="wairole:document"/>
        <dc:description xml:lang="en">The contents of the 
      associated element represent a definition (e.g., of a term or concept). 
      If there is a dfn element within the contents (as defined in [XHTMLMOD]), 
      then that represents the term being defined.
      </dc:description>
    </owl:Class>
    <owl:Class rdf:ID="main">
        <rdfs:subClassOf rdf:resource="wairole:region"/>
        <wairole:scope rdf:resource="wairole:document"/>
        <dc:description xml:lang="en">This defines the main 
      content of a document.
      </dc:description>
    </owl:Class>
    <owl:Class rdf:ID="navigation">
        <rdfs:subClassOf rdf:resource="wairole:region"/>
        <wairole:scope rdf:resource="wairole:document"/>
        <wairole:relatedConcept rdf:resource="wairole:menu"/>
        <dc:description xml:lang="en">This is the navigation bar 
      on a web document. This is typically a list of links to other pages on the 
      site or other areas of the same document.
      </dc:description>
    </owl:Class>
    <owl:Class rdf:ID="note">
        <rdfs:subClassOf rdf:resource="wairole:section"/>
        <wairole:scope rdf:resource="wairole:document"/>
        <dc:description xml:lang="en">The content is parenthetic 
      or ancillary to the main content of the resource.
      </dc:description>
    </owl:Class>
    <owl:Class rdf:ID="search">
        <rdfs:subClassOf rdf:resource="wairole:region"/>
        <wairole:scope rdf:resource="wairole:document"/>
        <dc:description xml:lang="en">This is the search section of 
      a web document. This is typically a form used to submit search 
      requests about the site or a more general Internet wide search service.
      </dc:description>
    </owl:Class>
    <owl:Class rdf:ID="secondary">
        <rdfs:subClassOf rdf:resource="wairole:region"/>
        <dc:description xml:lang="en">This is any unique section 
      of the document. In the case of a portal, this may include but not be 
      limited to: show times; current weather; or stocks to watch.
      </dc:description>
    </owl:Class>
    <owl:Class rdf:ID="seealso">
        <rdfs:subClassOf rdf:resource="wairole:section"/>
        <dc:description xml:lang="en">Indicates that the element 
      contains content that is related to the main content of the page.     
      </dc:description>
        <wairole:relatedConcept rdf:resource="#main"/>
    </owl:Class>
</rdf:RDF>

C.References

C.1.Normative References

C.2.Other References

D.Acknowledgments

At the time of publication, the participants in the W3C HTML Working Group were: