Footnotes

Footnotes are pieces of information that have several purposes, including citations, additional information (copyright, background), outside sources, and more. They are divided as follows:

The footnote call - The number that remains in the content, usually superscripted.
The footnote marker - The number displayed at the bottom of the page (the value matches the footnote call).
The footnote text - The value of the <fn> element, also displayed at the bottom of the page.

Footnotes - Built-in CSS

Footnote properties are defined in [PLUGIN_DIR]/css/print/p-foot-notes.css.

How to Change Style of the Footnote Markers and Footnote Calls

To bold the footnotes numbers, use some colors, and change the footnote marker, add the following rules to your customization CSS:

*[class ~= "topic/fn"]:footnote-call {
  font-weight: bold;
  color:red;
}

*[class ~= "topic/fn"]:footnote-marker {
  content: counter(footnote) " / ";
  font-weight: bold;
  color:red;
}

To indent the footnote content displayed at the end of the page, add the following rules to your customization CSS:

*[class ~= "topic/entry"] > *[class ~= "topic/fn"] {
  padding-left: 1in;
}

*[class ~= "topic/entry"] > *[class ~= "topic/fn"]:footnote-marker {
  margin-left: 1in;
}

How to Add a Separator Above the Footnotes

The @footnote part of a @page declaration controls the style of the separator between the page content and the footnotes. For the content, you should set a leader. The leader uses a letter or a line style to fill the entire width of the page.

@page {
  margin:0.5in;
  ...
  @footnote {
    content: leader(solid);
    color:silver;
  }
}

To create a dotted line, you can use the dot character: leader('.'). Other commonly used characters are: "-" (dash) and "_" (underscore).

How to Reset the Footnotes Counter

It is possible to reset the footnote counter. For example, if you want to reset the counter at the beginning of each chapter, add one of the following rules to your customization CSS:

@page chapter {
  counter-reset: footnote 1;
}

*[class ~= "bookmap/chapter"],
*[class ~= "topic/topic"][is-chapter] {
  counter-reset: footnote 1;
}

In a deep numbering context, you need to use the following rule instead:

*[class ~= "map/map"][numbering ^= 'deep'] *[class ~= "topic/topic"][is-chapter]:not([is-part]) {
  counter-reset: section1 0 footnote 1;
}

or can mark any element with an @outputclass value, match that value, and reset the counter at any point in your counter:

<p outputclass="reset-footnotes"/>

*[outputclass ~= "reset-footnotes"] {
  counter-reset: footnote 1;
}

How to Display Footnotes Below Tables

In your PDF output, you may want to group all the footnotes contained in a table just below it instead of having them displayed at the bottom of the page.

To add this functionality, use an Oxygen Publishing Template and follow these steps:

If you have not already created a Publishing Template, you need to create one. For details, see How to Create a Publishing Template.
Link the folder associated with the publishing template to your current project in the Project Explorer view.
Using the Project Explorer view, create an xslt folder inside the project root folder.

In the newly created folder, create an XSL file (for example, named merged2mergedExtension.xsl) with the following content:

<?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:opentopic-func="http://www.idiominc.com/opentopic/exsl/function"
  exclude-result-prefixes="xs opentopic-func" 
  version="3.0">
  
  <!--
    Match only top level tables (i.e tables that are not nested in other tables),
    that contains some footnotes.
  -->
  <xsl:template match="*[contains(@class, 'topic/table')]
    [not(ancestor::*[contains(@class, 'topic/table')])]
    [//*[contains(@class, 'topic/fn')]]">
    <xsl:next-match>
      <xsl:with-param name="top-level-table" select="." tunnel="yes"/>
    </xsl:next-match>
    <!-- Create a list with all the footnotes from the current table. -->
    <ol class="- topic/ol " outputclass="table-fn-container">
      <xsl:for-each select=".//*[contains(@class, 'topic/fn')]">
        <!--
          Try to preserve the footnote ID, if available, so that the xrefs will have a target.
        -->
        <li class="- topic/li " id="{if(@id) then @id else generate-id(.)}"
          outputclass="table-fn">
          <xsl:copy-of select="@callout"/>
          <xsl:apply-templates select="node()"/>
        </li>
      </xsl:for-each>
    </ol>
  </xsl:template>
  
  <!-- 
    The footnotes that have an ID must be ignored, they are accessible only 
    through existing xrefs (already present in the merged.xml file).
    
    The above template already made a copy of these footnotes in the OL element
    so it is not a problem if markup is not generated for them in the cell.
  -->
  <xsl:template
    match="*[contains(@class, 'topic/entry')]//*[contains(@class, 'topic/fn')][@id]"/>
  
  <!--
    The xrefs to footnotes with IDs inside table-cells. We need to recalculate
    their indexes if their referenced footnote is also in the table.
  -->
  <xsl:template match="*[contains(@class, 'topic/xref')][@type='fn']
    [ancestor::*[contains(@class, 'topic/entry')]]">
    <xsl:param name="top-level-table" tunnel="yes"/>
    <xsl:variable name="destination" select="opentopic-func:getDestinationId(@href)"/>
    <xsl:variable name="fn" select="
      $top-level-table//*[contains(@class, 'topic/fn')][@id = $destination]"/>
    <xsl:choose>
      <xsl:when test="$fn">
        <!-- There is a reference in the table, recalculate index. -->
        <xsl:variable name="fn-number" select="
          index-of($top-level-table//*[contains(@class, 'topic/fn')], $fn)"/>
        <xsl:copy>
          <xsl:apply-templates select="@*"/>
          <xsl:apply-templates select="$fn/@callout"/>
          <xsl:apply-templates select="node()
            except (text(), *[contains(@class, 'hi-d/sup')])"/>
          <sup class="+ topic/ph hi-d/sup ">
            <xsl:apply-templates select="child::*[contains(@class, 'hi-d/sup')]/@*"/>
            <xsl:value-of select="$fn-number"/>
          </sup>
        </xsl:copy>
      </xsl:when>
      <xsl:otherwise>
        <!-- There is no reference in the table, keep original index. -->
        <xsl:next-match/>
      </xsl:otherwise>
    </xsl:choose>
  </xsl:template>
  
  <!-- 
    The footnotes without ID inside table-cells. They are copied in the OL element, but have 
    no xrefs pointing to them (because they have no ID), so xrefs are generated. 
  -->
  <xsl:template
    match="*[contains(@class, 'topic/entry')]//*[contains(@class, 'topic/fn')][not(@id)]">
    <!-- Determine the footnote index in the document order. -->
    <xsl:param name="top-level-table" tunnel="yes"/>
    <xsl:variable name="fn-number" select="
      index-of($top-level-table//*[contains(@class, 'topic/fn')], .)"/>
    <xref type="fn" class="- topic/xref "
      href="#{generate-id(.)}" outputclass="table-fn-call">
      <xsl:copy-of select="@callout"/>
      <!-- Generate an extra <sup>, identical to what DITA-OT generates for other xrefs. -->
      <sup class="+ topic/ph hi-d/sup ">
        <xsl:value-of select="$fn-number"/>
      </sup>
    </xref>
  </xsl:template>
  
</xsl:stylesheet>

Open the template descriptor file associated with your publishing template (the .opt file) and set the XSLT stylesheet created in the previous step with the com.oxygenxml.pdf.css.xsl.merged2merged XSLT extension point:
```
<publishing-template>
 ...
 <pdf>
  ...        
  <xslt>
    <extension
      id="com.oxygenxml.pdf.css.xsl.merged2merged"
      file="xslt/merged2mergedExtension.xsl"/>
   </xslt>
```

Create a css folder in the publishing template directory. In this directory, save a custom CSS file with rules that style the glossary structure. For example:

/* Customize footnote calls, inside the table. */
*[outputclass ~= 'table-fn-call'] {
  line-height: none;
}
*[class ~= "topic/table"] *[class ~= "topic/xref"][type = 'fn'][callout] *[class ~= "hi-d/sup"] {
  content: oxy_xpath("ancestor::*[contains(@class, 'topic/xref')]/@callout");
}

/* Customize the list containing all the table footnotes. */
*[outputclass ~= 'table-fn-container'] {
  border-top: 1pt solid black;
  counter-reset: table-footnote;
}

/* Customize footnotes display, below the table. */
*[outputclass ~= 'table-fn'] {
  font-size: smaller;
  counter-increment: table-footnote;
}
*[outputclass ~= 'table-fn']::marker {
  font-size: smaller;
  content: "(" counter(table-footnote) ")";
}
*[outputclass ~= 'table-fn'][callout]::marker {
  content: "(" attr(callout) ")";
}

/* Customize xrefs pointing to footnotes, inside the table. */
*[class ~= "topic/table"] *[class ~= "topic/xref"][type = 'fn'] {
  color: unset;
  text-decoration: none;
}
*[class ~= "topic/table"] *[class ~= "topic/xref"][type = 'fn']:after {
  content: none;
}
*[class ~= "topic/table"] *[class ~= "topic/xref"][type = 'fn'] *[class ~= "hi-d/sup"]:before {
  content: "(";
}
*[class ~= "topic/table"] *[class ~= "topic/xref"][type = 'fn'] *[class ~= "hi-d/sup"]:after {
  content: ")";
}

Open the template descriptor file associated with your publishing template (the .opt file) and reference your custom CSS file in the resources element:

<publishing-template>
  ...
  <pdf>
    ...                
    <resources>            
      <css file="css/custom.css"/>
    </resources>

Edit the DITA Map PDF - based on HTML5 & CSS transformation scenario.
In the Templates tab, click the Choose Custom Publishing Template link and select your template.
Click OK to save the changes and run the transformation scenario.