Assign CSS class to element in an XSL

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"&gt;
 <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:

1. Only simple templates and <xsl:apply-templates> are used. Therefore, the chances of committing an error are minimized.

2. 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.

3. 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.