[FEATURE] PDF export: add bookmarks to headings

[alexanderino]

Currently, when a note is exported to PDF, QOwnNotes does not add bookmarks to headings. Bookmarks are essential for document navigation and document structure.

Here are screenshots of PDFs with and without bookmarks.

PDF exported by QOwnNotes. Note how the 'Document outline' option near the top left is greyed out:

PDF created using LibreOffice, after copy-pasting QOwnNotes's preview panel contents:

Resources

While I'm no programmer, I believe the following links may be of use:

• List of All Members for QPdfWriter
• QPdfBookmarkModel Class
• Troubleshooting QPdfBookmarkModel: A Guide to Common Issues

[pbek]

Good question, currently QPrinter is used.

[alexanderino]

As always, I'm happy to perform any testing.

[pbek]

QPdfBookmarkModel cannot be used to create PDF outlines/bookmarks. It's a read-only model class introduced in Qt 6.4 for displaying bookmarks from existing PDF files in a tree view - not for creating them. 😬

With Qt itself, we currently can't do it.
Only works with external C++ libraries.
Which operating system are you on? 😅

[alexanderino]

Which operating system are you on? 😅

Windows 11 and 10.

[pbek]

Hard to get external dependencies, like https://github.com/podofo/podofo at build time there... ️🤷🏻

[alexanderino]

True. I can see this is not a trivial task.

What does LibreOffice use to create PDFs from Writer, etc.? Is it something that can be adapted for QOwnNotes? Here is the source code on Github and source build documentation.

[pbek]

In what way would pulling the dozens of dependencies of LibreOffice (https://github.com/NixOS/nixpkgs/blob/master/pkgs/applications/office/libreoffice/default.nix) into the project an improvement over having https://github.com/podofo/podofo?

[pbek]

So far I didn't even have luck with implementing it with podofo on Linux.