tdf#153047 sw: fix PDF export of content controls in placeholder mode

Importing an inline content control from DOCX used to be just plain text
in Writer, so the PDF export of that was also just plain text.

Now that content controls are actually supported, we used to not emit
them as plain text in the PDF export, since
82d90529dc2b3cb8359dec78852cbd910a66d275 (sw content controls, rich
text: add initial PDF export, 2022-09-12). Part of this was to write the
string value of the content control as the /V (value) key of the form,
when it's not in placeholder mode. This made sure that once the form is
filled in, no overlap between the plain text and the filled in text
happens.

Try to support both use-cases at the same time by also mapping the value
of the content control to /V, even if it's in placeholder mode. This
keeps avoiding the unwanted overlap, but this way the placeholder text
is no longer lost on PDF export.

An alternative would have been to map the placeholder text to
description when the alias/title is empty, but that would show up only
as a mouse tooltip, so won't change the behavior when the PDF is
printed.

Change-Id: I9408b5abe36af28cd00845a74a3dfff13973b83a
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/145828
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
(cherry picked from commit 14da39fcfffe8006a79971ac0b670e12d0d7a0ea)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/146017
Reviewed-by: Xisco Fauli <xiscofauli@libreoffice.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/vcl/filter/PDFiumLibrary.hxx b/include/vcl/filter/PDFiumLibrary.hxx
index 347b64619045..9c278d281a1c 100644
--- a/include/vcl/filter/PDFiumLibrary.hxx
+++ b/include/vcl/filter/PDFiumLibrary.hxx
@@ -110,6 +110,7 @@ public:
     virtual OUString getFormAdditionalActionJavaScript(PDFiumDocument* pDoc,
                                                        PDFAnnotAActionType eEvent)
         = 0;
+    virtual OUString getFormFieldValue(PDFiumDocument* pDoc) = 0;
 };
 
 class PDFiumTextPage;