Assign CSS class to element in an XSL - xslt

Question

My XML file is as follows:
<worksheet>
<row>
<rowTitle>RT1</rowTitle>
<rowType>yesorno</rowType>
<subLine>subLine1Content</subLine>
<subLine>subLine2Content</subLine>
</row>
<row>
<rowTitle>RT2</rowTitle>
<rowType>operation</rowType>
<subLine>subLine1Content</subLine>
<subLine>subLine2Content</subLine>
<subLine>subLine3Content</subLine>
</row>
.
.
</worksheet>
in my xsl, while displaying contents of a particular row, i'd like to add a class to the html element that'll specify the type of the row it is. I tried using xsl:choose and assigning value to a xsl:variable, but that doesn't work.
I'm trying to display the row as
<ol>
<li class="rowTypeBoolean">
RT1
<ul><li>subLineContent1</li>
<li>subLineContent2</li></ul>
</li>
<li class="rowTypeOptions">
RT2
<ul><li>subLineContent1</li>
<li>subLineContent2</li>
<li>subLineContent3</li></ul>
</li>
.
.
</ol>
XSL file snippet
<xsl:template match="row">
<li class="rowClass ${className}">
<xsl:choose>
<xsl:when test="type = 'YESORNO'">
<xsl:variable name="className" select="rowTypeBoolean"/>
</xsl:when>
<xsl:when test="type = 'OPTIONS'">
<xsl:variable name="className" select="rowTypeOptions"/>
</xsl:when>
<xsl:when test="type = 'OPERATION'">
<xsl:variable name="className" select="rowTypeOperation"/>
</xsl:when>
<xsl:otherwise>
<xsl:variable name="className" select="rowTypeOther"/>
</xsl:otherwise>
</xsl:choose>
<span class="rowTitleClass">
<xsl:value-of select="rowtitle"/>
</span>
<br/>
<ul class="subLineListClass">
<xsl:apply-templates select="subLine"/>
</ul>
</li>
</xsl:template>

Answer 1

You need to add it as an attribute to the element:
<li>
<xsl:choose>
<xsl:when test="type = 'YESORNO'">
<xsl:attribute name="className">rowTypeBoolean</xsl:attribute>
</xsl:when>
<xsl:when test="type = 'OPTIONS'">
<xsl:attribute name="className">rowTypeOptions</xsl:attribute>
</xsl:when>
<xsl:when test="type = 'OPERATION'">
<xsl:attribute name="className">rowTypeOperation"</xsl:attribute>
</xsl:when>
<xsl:otherwise>
<xsl:attribute name="className">rowTypeOther"</xsl:attribute>
</xsl:otherwise>
</xsl:choose>
</li>

Answer 2

The most naive solution would be to use xsl:choose instruction like this:
<li>
<xsl:attribute name="className">
<xsl:choose>
<xsl:when test="type = 'YESORNO'">rowTypeBoolean</xsl:when>
<xsl:when test="type = 'OPTIONS'">rowTypeOptions</xsl:when>
<xsl:when test="type = 'OPERATION'">rowTypeOperation</xsl:when>
<xsl:otherwise>rowTypeOther</xsl:otherwise>
</xsl:choose>
</xsl:attribute>
</li>
Other way would be to have an inline map (or via fn:document()) like:
<li class="{$map[#type = current()/type]|$map[not(#type)]}"/>
With this as top level element
<map:map xmlns:map="map">
<item type="YESORNO">rowTypeBoolean</item>
<item type="OPTIONS">rowTypeOption</item>
<item type="OPERATIONS">rowTypeOperation</item>
<item>rowTypeOther</item>
</map:map>
<xsl:variable name="map" select="document('')/*/map:map/*" xmlns:map="map"/>

Answer 3

It isn't necessary at all to use <xsl:choose> in the transformation:
This transformation:
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:strip-space elements="*"/>
<xsl:template match="node()|#*">
<xsl:copy>
<xsl:apply-templates select="node()|#*"/>
</xsl:copy>
</xsl:template>
<xsl:template match="worksheet">
<ol>
<xsl:apply-templates/>
</ol>
</xsl:template>
<xsl:template match="row[rowType='yesorno']">
<li class="rowTypeBoolean">
<xsl:apply-templates/>
</li>
</xsl:template>
<xsl:template match="row[rowType='operation']">
<li class="rowTypeOperation">
<xsl:apply-templates/>
</li>
</xsl:template>
<xsl:template match="row[rowType='options']">
<li class="rowTypeOptions">
<xsl:apply-templates/>
</li>
</xsl:template>
<xsl:template match="row">
<li class="rowTypeOther">
<xsl:apply-templates/>
</li>
</xsl:template>
<xsl:template match="subLine[1]">
<ul>
<xsl:apply-templates select="../subLine" mode="process"/>
</ul>
</xsl:template>
<xsl:template match="subLine" mode="process">
<li><xsl:apply-templates/></li>
</xsl:template>
</xsl:stylesheet>
when applied on the provided XML document:
<worksheet>
<row>
<rowTitle>RT1</rowTitle>
<rowType>yesorno</rowType>
<subLine>subLine1Content</subLine>
<subLine>subLine2Content</subLine>
</row>
<row>
<rowTitle>RT2</rowTitle>
<rowType>operation</rowType>
<subLine>subLine1Content</subLine>
<subLine>subLine2Content</subLine>
<subLine>subLine3Content</subLine>
</row>
</worksheet>
produces the wanted, correct result:
<ol>
<li class="rowTypeBoolean">
<rowTitle>RT1</rowTitle>
<rowType>yesorno</rowType>
<ul>
<li>subLine1Content</li>
<li>subLine2Content</li>
</ul>
<subLine>subLine2Content</subLine>
</li>
<li class="rowTypeOperation">
<rowTitle>RT2</rowTitle>
<rowType>operation</rowType>
<ul>
<li>subLine1Content</li>
<li>subLine2Content</li>
<li>subLine3Content</li>
</ul>
<subLine>subLine2Content</subLine>
<subLine>subLine3Content</subLine>
</li>
</ol>
Do note:
Only simple templates and <xsl:apply-templates> are used. Therefore, the chances of committing an error are minimized.
This code is inherently extensible and maintainable. If a new row type is introduced none of the existing templates will need to be altered -- just a new short and simple template will need to be added, that matches a row element having a rowType child with the new value.
The mapping between rowType and the corresponding value of the class attribute can be specified in a special global-level namespaced element and/or variable (as done in Alejandro's solution), or even in a separate XML document. Then we can have just one single template, matching row.