PDF Annotations and Fields: Read Only versus Locked versus Locked Contents

Below are the descriptions listed in the PDF Reference 1.7 that I am putting here as a reference in determining how we should handle these fields.

TABLE 8.16 Annotation flags

ReadOnly
(PDF 1.3) If set, do not allow the annotation to interact with the user. The annotation may be displayed or printed (depending on the settings of the NoView and Print flags) but should not respond to mouse clicks or change its appearance in response to mouse motions.
Note: This flag is ignored for widget annotations; its function is subsumed by the ReadOnly flag of the associated form field (see Table 8.70 on page 676).

Locked
(PDF 1.4) If set, do not allow the annotation to be deleted or its properties (including position and size) to be modified by the user. However, this flag does not restrict changes to the annotation’s contents, such as the value of a form field. (See implementation note 84 in Appendix H.)

LockedContents
(PDF 1.7) If set, do not allow the contents of the annotation to be modified by the user. This flag does not restrict deletion of the annotation or changes to other annotation properties, such as position and size.

TABLE 8.70 Field flags common to all field types

ReadOnly
If set, the user may not change the value of the field. Any associated widget annotations will not interact with the user; that is, they will not respond to mouse clicks or change their appearance in response to mouse motions. This flag is useful for fields whose values are computed or imported from a database.

Appendix H.

Note 84
Acrobat 5.0 obeys the Locked flag only for widget annotations. In Acrobat 6.0, markup annotations support it as well.


How Flags Work In User Interface

Qoppa’s PDF components behave the same as Adobe’s products when it comes to handling this field in the user interface, to match what Adobe does.

  • Read Only
    • Links: Link action works, able to move or resize, able to edit actions in properties, able to edit appearance properties, able to delete
    • Fields: Unable to type in field, able to move or resize, able to edit all properties, able to delete
    • Annotations: NOT able to move or resize, NOT able to edit appearance properties, NOT able to delete
  • Locked
    • Links: Link action works, NOT able to move or resize, NOT able to edit actions in properties, NOT able to edit appearance properties, NOT able to delete
    • Fields: able to type in field, NOT able to move or resize, NOT able to edit any properties, NOT able to delete
    • Annotations: NOT able to move or resize, NOT able to edit appearance properties, NOT able to delete
  • Locked Contents
    • Links: Link action works, able to move or resize, able to edit actions in properties, able to edit appearance properties, able to delete
    • Fields: able to type in field, able to move or resize, able to edit all properties, able to delete
    • Annotations: able to move or resize, able to edit appearance properties, able to delete, NOT able to edit annotation content (note)