Transforming RSS into HTML and WAP II (2/2) - exploring XML

WML output

The Wireless Markup Language (WML) is a smaller and less powerful variant of HTML, conceived as the display markup for mobile phones and PDAs. Details can be found in column12.

Differences between HTML and WML

A WML response consists of a so-called "deck of cards" representing multiple pages, not only one page.

Table formatting is not supported.

Links are defined as a mixture of do and go elements.

The exact rendering of UI elements is left to the particular user agent.

<?xml version="1.0" ?> <xsl:stylesheet xmlns:xsl="http://www.w3.org/XSL/Transform/1.0">
<xsl:output method="wml"/>

<xsl:template match="/"> <WML><CARD ID="id1" TITLE="RSS newsfeed"> <xsl:apply-templates/> </CARD></WML> </xsl:template>

<xsl:template match="channel"> <DO TYPE="accept"> <xsl:attribute name="LABEL"> <xsl:value-of select="title"/> </xsl:attribute> <GO> <xsl:attribute name="HREF"> <xsl:value-of select="link"/> </xsl:attribute> </GO> </DO> </xsl:template> <xsl:template match="item"> <DO TYPE="accept"> <xsl:attribute name="label"> <xsl:value-of select="title"/> </xsl:attribute> <GO> <xsl:attribute name="HREF"> <xsl:value-of select="link"/> </xsl:attribute> </GO> </DO> </xsl:template> <xsl:template match="text()"/> </xsl:stylesheet>

RSS2WML

WML output

Conclusion

XSL is a flexible solution for converting an XML-based input format such as RSS into various output formats. The case study here demonstrated the transformation into HTML with CSS and WAP/WML. Non-XML based output such as RTF, PDF, GIF etc. is also possible, and we might get back to this topic in a later installment of this column.