For subjects within the <hasNarrower> element, the container subject is more general than each of the contained subjects. That is, this element makes the default hierarchical relationship explicit, although the way in which a relationship is narrower is not specified.
These models represent only the default document types distributed by OASIS. Actual content models will differ with each new document type.
|subjectScheme||( (topicmeta) (optional) then (data or data-about or subjectdef or subjectHead or topicref or (anchorref or keydef or mapref or topicgroup or topichead or topicset or topicsetref) ) (any number) )|
- map/topicref subjectScheme/hasNarrower
This example specifies that Planting Roses is a narrower subject category than Horticulture, although it is part of the Horticulture subject area.
<subjectScheme> <hasNarrower> <subjectdef keys="horticulture" navtitle="Horticulture"> <subjectdef keys="plantrose" navtitle="Planting Roses"/> </subjectdef> </hasNarrower> </subjectScheme>
|Name||Description||Data Type||Default Value||Required?|
|navtitle||Specifies the title of the topic as it will appear in the navigation or tables of contents that are generated from the map. Beginning with DITA 1.2, the preferred way to specify the navigation title in a map is with the navtitle element, available inside the topicmeta element.||CDATA||#IMPLIED||No|
|href||A pointer to the resource represented by the <topicref>. See The href attribute for detailed information on supported values and processing implications. References to DITA content cannot be below the topic level: that is, you cannot reference individual elements inside a topic. References to content other than DITA topics should use the format attribute to identify the kind of resource being referenced.||CDATA||#IMPLIED||No|
|keys||Introduces one or more global identifiers for a resource referenced from a map. See The keys attribute for details on how to use the keys attribute.||NMTOKEN||#IMPLIED||No|
|processing-role||Describes the processing role of the referenced topic. The
processing default is "normal".
If the value is not specified locally, but
is specified on an ancestor, the value will cascade from the closest
||(normal | resource-only | -dita-use-conref-target)||#IMPLIED||No|
|scope||The scope attribute identifies the closeness of the relationship between the current document and the target resource. See The scope attribute for more information on values.||(local | peer | external | -dita-use-conref-target)||#IMPLIED||No|
|format||The format attribute identifies the format of the resource being referenced. See The format attribute for details on supported values.||CDATA||#IMPLIED||No|
|type||Describes the target of a reference. See The type attribute for detailed information on supported values and processing implications.||CDATA||#IMPLIED||No|
|univ-atts attribute group (includes select-atts, id-atts, and localization-atts groups)||A set of related attributes, described in univ-atts attribute group|
|global-atts attribute group (xtrf, xtrc)||A set of related attributes, described in global-atts attribute group|
|class, outputclass, keyref||Keyref provides a redirectable reference based on a key defined within a map. See The keyref attribute for information on using this attribute. Class and outputclass are described in Other common DITA attributes|