Example: Creating a simple PDF plug-inSimple PDF plug-in exampleThis scenario walks through the process of creating a very simple plug-in
(com.example.print-pdf) that creates a new transformation type: .
The transformation has the following characteristics:
Uses A4 paper
Renders figures with a title at the top and a description at the bottom
Use em dashes as the symbols for unordered lists
In the plugins directory, create a directory named
com.example.print-pdf.In the new com.example.print-pdf directory, create a plug-in configuration file
(plugin.xml) that declares the new transformation and its
dependencies.<filepath>plugin.xml</filepath> file<?xml version='1.0' encoding='UTF-8'?>
<plugin id="com.example.print-pdf">
<require plugin="org.dita.pdf2"/>
<feature extension="dita.conductor.transtype.check" value="print-pdf"/>
<feature extension="dita.transtype.print" value="print-pdf"/>
<feature extension="dita.conductor.target.relative" file="integrator.xml"/>
</plugin>Add an Ant script (integrator.xml) to define the transformation type.<filepath>integrator.xml</filepath> file<?xml version='1.0' encoding='UTF-8'?>
<project name="com.example.print-pdf">
<target name="dita2print-pdf.init">
<property name="customization.dir" location="${dita.plugin.com.example.print-pdf.dir}/cfg"/>
</target>
<target name="dita2print-pdf" depends="dita2print-pdf.init, dita2pdf2"/>
</project>In the new plug-in directory, add a cfg/catalog.xml file that specifies the custom
XSLT style sheets.<filepath>cfg/catalog.xml</filepath> file<?xml version="1.0" encoding="UTF-8"?>
<catalog prefer="system" xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
<uri name="cfg:fo/attrs/custom.xsl" uri="fo/attrs/custom.xsl"/>
<uri name="cfg:fo/xsl/custom.xsl" uri="fo/xsl/custom.xsl"/>
</catalog>Create the cfg/fo/attrs/custom.xsl file, and add attribute and variable overrides to
it.For example, add the content highlighted with bold to change the page size to A4.<filepath>cfg/fo/attrs/custom.xsl</filepath> file<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
version="2.0">
<!-- Change page size to A4 -->
<xsl:variable name="page-width">210mm</xsl:variable>
<xsl:variable name="page-height">297mm</xsl:variable>
</xsl:stylesheet>Create the cfg/fo/xsl/custom.xsl file, and add XSLT overrides to it.For example, the following code changes the rendering of figure elements.<filepath>cfg/fo/xsl/custom.xsl</filepath> file<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:fo="http://www.w3.org/1999/XSL/Format"
version="2.0">
<!-- Move figure title to top and description to bottom -->
<xsl:template match="*[contains(@class,' topic/fig ')]">
<fo:block xsl:use-attribute-sets="fig">
<xsl:call-template name="commonattributes"/>
<xsl:if test="not(@id)">
<xsl:attribute name="id">
<xsl:call-template name="get-id"/>
</xsl:attribute>
</xsl:if>
<xsl:apply-templates select="*[contains(@class,' topic/title ')]"/>
<xsl:apply-templates select="*[not(contains(@class,' topic/title ') or contains(@class,' topic/desc '))]"/>
<xsl:apply-templates select="*[contains(@class,' topic/desc ')]"/>
</fo:block>
</xsl:template>
</xsl:stylesheet>Create an English-language variable-definition file (cfg/common/vars/en.xml) and make
any necessary modifications to it.For example, the following code removes the period after the number for an ordered-list item; it also
specifies that the bullet for an unordered list item should be an em dash.<filepath>cfg/common/vars/en.xml</filepath> file<?xml version="1.0" encoding="UTF-8"?>
<vars xmlns="http://www.idiominc.com/opentopic/vars">
<!-- Remove dot from list number -->
<variable id="Ordered List Number"><param ref-name="number"/></variable>
<!-- Change unordered list bullet to an em dash -->
<variable id="Unordered List bullet">—</variable>
</vars>
The new plug-in directory has the following layout and files: