CHAPTER 8
608
Interactive Features
KEY
TYPE
VALUE
StructParent
integer
(Required if the annotation is a structural content item; PDF 1.3)
The integer key
of the annotation’s entry in the structural parent tree (see “Finding Structure El-
(Optional; PDF 1.5)
An optional content group or optional content member-
ship dictionary (see Section 4.10, “Optional Content”) specifying the optional
content properties for the annotation. Before the annotation is drawn, its visi-
bility is determined based on this entry as well as the annotation flags specified
in the
F
entry (see Section 8.4.2, “Annotation Flags”). If it is determined to be
invisible, the annotation is skipped, as if it were not in the document.
OC
dictionary
8.4.2 Annotation Flags
The value of the annotation dictionary’s
F
entry is an unsigned 32-bit integer con-
taining flags specifying various characteristics of the annotation. Bit positions
within the flag word are numbered from 1 (low-order) to 32 (high-order). Table
be set to 0.
TABLE 8.16 Annotation flags
BIT POSITION
NAME
MEANING
1
Invisible
If set, do not display the annotation if it does not belong to one of the stan-
dard annotation types and no annotation handler is available. If clear, display
such an unknown annotation using an appearance stream specified by its ap-
pearance dictionary, if any (see Section 8.4.4, “Appearance Streams”).
(PDF 1.2)
If set, do not display or print the annotation or allow it to interact
with the user, regardless of its annotation type or whether an annotation
handler is available. In cases where screen space is limited, the ability to hide
and show annotations selectively can be used in combination with appearance
streams (see Section 8.4.4, “Appearance Streams”) to display auxiliary pop-up
information similar in function to online help systems. (See implementation
(PDF 1.2)
If set, print the annotation when the page is printed. If clear, never
print the annotation, regardless of whether it is displayed on the screen. This
can be useful, for example, for annotations representing interactive pushbut-
tons, which would serve no meaningful purpose on the printed page. (See
2
Hidden
3
Print