Introducing The Mobility Tags - BEA WebLogic User Manual

Part III Fundamentals of Mobile Content

Introducing the Mobility Tags

This section introduces the mobility tags; the WebLogic Mobility Server authoring extensions to
XHTML. It gives a brief background of XHTML and shows how the mobility tags extend and
conform to this schema.
The History of XHTML
was originally designed for publishing hypertext on the World Wide Web. HTML is a non-
HTML
proprietary format based on SGML. Variations in HTML language definitions have emerged in
the form of browser-specific implementations. These variations, combined with the increasing
availability and diverse capabilities of non-desktop browsers, such as PDAs and mobile phones,
have made it difficult for designers to settle on a system for targeting a range of devices. Many
developers found themselves having to take a "lowest common denominator" approach when
trying to combine content, physical layout and interactive behavior of a web application designed
for a broad spectrum of client devices.
, created by the World Wide Web Consortium
XHTML (Extensible Hypertext Mark-up Language)
W3C, addresses this issue. XHTML takes advantage of the more powerful meta-language XML
and thus requires that documents be "well-formed". Variations are not allowed. The strict mark-
up standards are what allow extensibility of the core tag set to extend functionality.
XHTML 1.0 has replaced HTML as the official Web mark-up standard according to the W3C.
XHTML is also the content authoring language specified by WAP 2.0 and XHTML Mobile
Profile, used by many handheld devices, is a subset of XHTML.
XHTML looks a lot like HTML but has more rigid mark-up standards. XHTML documents must
strictly conform to these standards, that is, be "well-formed". For more on these standards and
how to convert existing HTML to XHTML, see working with XHTML in this manual.
Extend XHTML with the Mobility Tags
WebLogic Mobility Server has added a module to XHTML, called , or
multi-mode XHTML
mmXHTML . This module is a set of XML elements that simplifies the task of structuring and
presenting web applications on a range of devices including PCs, PDAs and web-enabled phones.
By adding these tags to "well-formed" web content, authors can create documents that can be
displayed on a variety of devices. The WebLogic Mobility Server transformation engine
interprets the tags and translates the XHTML content into the language understood by the
requesting device. The mmXHTML tags also give content authors the power take a single source
of content and re-organize and style the layout in a ways that best suit various desktop and mobile
devices.
A JSP tag library version of the mmXHTML tags is also available for use with JSP files. These
tags are almost identical in syntax and function. They are explained further in The WebLogic
Mobility Server JSP Tag Library in this manual.
18 - BEA WebLogic Mobility Server User Guide