Adobe Acrobat SDK
Implementation Notes
Adobe® Supplement to the ISO 32000
Implementation Notes to the PDF Reference, sixth edition 121
8.5.3 Action Types (Hide Actions)
109. Acrobat viewers earlier than version 3.0 report the following error when encountering an action of type
Hide
: “The plug-in needed for this
Hide
action is not available.”
110. In Acrobat viewers, the change in an annotation’s Hidden flag as a result of a hide action is temporary in
that the user can subsequently close the document without being prompted to save changes and the
effect of the hide action is lost. However, if the user explicitly saves the document before closing, such
changes are saved and thus become permanent.
8.5.3 Action Types (Named Actions)
111. Acrobat viewers earlier than version 3.0 report the following error when encountering an action of type
Named
: “The plug-in needed for this
Named
action is not available.”
112. Acrobat viewers extend the list of named actions in Table 8.61 to include most of the menu item names
available in the viewer.
8.6.1 Interactive Form Dictionary
113. Acrobat viewers may insert additional entries in the
DR
resource dictionary, such as
Encoding
, as a
convenience for keeping track of objects being used to construct form fields. Such objects are not
actually resources and are not referenced from the appearance stream.
114. In Acrobat, markup annotations can also make use of the resources in the
DR
dictionary.
115. Acrobat 6.0 recognizes only the stream value of the
XFA
entry; Acrobat 6.02 and later recognize both
stream and array values.
8.6.2 Field Dictionaries (Field Names)
116. Beginning in Acrobat 3.0, partial field names cannot contain a period.
117. Acrobat 6.0 and later support Unicode encoding of field names. Versions earlier than Acrobat 6.0 do
not support Unicode encoding of field names.
8.6.2 Field Dictionaries (Variable Text)
118. In PDF 1.2, an additional entry in the field dictionary,
DR
, was defined but was never implemented.
Beginning with PDF 1.5, this entry is obsolete and should be ignored.
119. If the
MK
entry is present in the field’s widget annotation dictionary (see Table 8.39), Acrobat viewers
regenerate the entire XObject appearance stream. If
MK
is not present, the contents of the stream
outside
/Tx BMC...EMC
are preserved.
8.6.2 Field Dictionaries (Rich Text Strings)
120. To select a font specified by attributes in a rich text string, Acrobat 6.0 follows this sequence, choosing
the first appropriate font it finds:
a. A font in the default resource dictionary (specified by the document’s
DR
entry; see Table 8.67)
whose font descriptor information matches the font specification in the rich text string. “Font
Characteristics” on page 892 describes how this matching is done.
