Behavioral Extensions to CSS

W3C Working Group Note 14 October 2014

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Ian Hickson, Google, Inc.
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This Note replaces a proposal for features in CSS that allow to bind “behaviors” to the elements of a document. A “behavior” is defined by a URL and typically points to an object (in a language such as XBL [XBL]) that defines its own appearance and user interaction. Such a binding allows, e.g. to replace an element by a complex user interface control. The features are no longer being developed.

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/.

Publication as a Working Group Note 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.

This document was produced by the CSS Working Group (part of the Style Activity).

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This document is governed by the 1 August 2014 W3C Process Document.

The CSS Working Group does not expect further work on this document.

Table of contents

1. Summary

In 1999, the CSS working group worked on a Behavioral Extensions to CSS specification that proposed syntax for actual binding definitions. Since then, separate languages have been developed for this purpose (e.g. XBL [XBL]), and the CSS-specific way of defining bindings was dropped.

The proposed role of CSS then became only to attach the external object defined in XBL to an element in a document, via a ‘binding’ property that takes a URL as value.

Insufficient interest in XBL and the ‘binding’ property made the CSS Working Group decide to stop the development of the specification. (For the same reason, the Web Applications Working Group decided to halt the development of XBL.)

Note that for the specific case of documents in HTML [HTML5], the HTML Working Group has developed an alternative solution. (See the template element.)

2. References

Ian Hickson; et al. HTML5. 16 September 2014. W3C Proposed Recommendation. (Work in progress.) URL: http://www.w3.org/TR/2014/PR-html5-20140916/
Ian Hickson. XBL 2.0. 24 May 2012. W3C Working Group Note. URL: http://www.w3.org/TR/2012/NOTE-xbl-20120524/