Topic metadata can be specified in a DITA map as well as in the topics that the map
references. By default, metadata in the map supplements or overrides metadata that is specified
at the topic level, unless the @lockmeta
attribute of the <topicmeta>
element is set to "no".
<topicref>
element, or as metadata attributes or elements in the
topic itself:At the map level, properties can be set by using metadata elements. They can be set
for an individual topic, for a set of topics, or globally for the entire document.
The metadata elements are authored within a <topicmeta>
element, which associates metadata with the parent element and its children. Because
the topics in a branch of the hierarchy typically have some common subjects or
properties, this is a convenient mechanism to define properties for a set of topics.
For example, the <topicmeta>
element in a
<relcolspec>
can associate metadata with all the topics
that are referenced in the <reltable>
column.
A map can override or supplement everything about a topic except its primary title
and body content. All the metadata elements that are available in a topic also are
available in a map. In addition, a map can provide
alternate titles and a short description. The alternate titles can override their
equivalent titles in the topic. The short
description in the map MAY override the short
description in the topic if the <topicref>
element specifies
a @copy-to
attribute.
<topicref>
element<topicref>
element. <prolog>
element.In a topic, the metadata elements apply to the entire topic. In a map, they supplement or
override any metadata that is provided in the referenced topics. When the same metadata
element or attribute is specified in both a map and a topic, by default the value in the map
takes precedence; the assumption here is that the author of the map has more knowledge of
the reusing context than the author of the topic. The @lockmeta
attribute on
the <topicmeta>
element controls whether map-specified values
override values in the referenced topic.
The <navtitle>
element is an exception to the rule of how metadata
specified by the <topicmeta>
element cascades. The content of the
<navtitle>
element is used as a navigation title only if the
@locktitle
attribute of the parent <topicref>
element is set to "yes".