callout
callout — A “called out” description of a marked area.
Synopsis
callout ::= ![[-]](figs/web/nav/down.gif)
![[+]](figs/web/nav/right.gif)
- One or more of:
annotationbridgeheadremarkrevhistory- Indexing inlines
- Admonition elements
- Formal elements
- Graphic elements
- Informal elements
informalequationinformalexampleinformalfigureinformaltable(db.cals.informaltable)informaltable(db.html.informaltable)
- List elements
- Paragraph elements
- Publishing elements
- Synopsis elements
- Technical elements
- Verbatim elements
Attributes
Additional attributes:
- arearefs (IDREFS)
Required attributes are shown in bold.
Description
A “callout” is a visual device for associating annotations with an image, program listing, or similar figure. Each location is identified with a mark, and the annotation is identified with the same mark. This is somewhat analogous to the notion of footnotes in print.
An example will help illustrate the concept. In the following example, the synopsis for the mv command is annotated with two marks. Note the location of the old and new filenames.
mvoldfilenewfile
Somewhere else in the document, usually close by, a
calloutlist provides a description for each of the
callouts:
| The old filename. The mv command renames
the file currently called |
| The new filename. The mv command changes
the name of the old file to |
Each callout contains an annotation for an
individual callout or a group of callouts. The
callout points to the areas that it annotates with
ID references. The areas are identified by
coordinates in an area or areaset,
or by an explicit co element.
Processing expectations
Formatted as a displayed block.
A callout usually generates text that points
the reader to the appropriate area on the object being augmented.
Often, these are numbered bullets or other distinct visual icons. The
same icons should be used in both places. In other words, whatever
identifies the callouts on the object should generate the same icons
on the respective callouts.
In online environments, it may also be possible to establish a linking relationship between the two elements.
The processing expectations of callouts are
likely to deserve special consideration for interchange. See Appendix D, Interchanging DocBook Documents. This is especially true if your
interchange partners are producing documentation in a medium that has
restricted visual presentation features, such as aural media or
Braille.
Parents
These elements contain callout: calloutlist.