Qt5 and KF5 in LibreOffice

[Jan-Marek Glogowski]

Hi Heiko,

I thought your questions are of general interest, so I added the development mailing list, also for further discussion / coordination.

Am 3. Dezember 2017 22:17:52 MEZ schrieb Heiko Becker <heirecka at exherbo.org>:
>it seems you're the author of the Qt5/KF5 vcl plugins in LibreOffice. I
>wondered what's the status of those with 6.0.0.0-beta1?

The plugin is currently not usable! And if nobody else then me contributes, it won't be usable for 6.0, even without any implemented Qt theming.
And even when using the cairo text renderer - by exporting SAL_VCL_QT5_USE_CAIRO - there remains a lot of missing basic functionality, like properly working (popup) menus.

In hindsight the master merge of the feature branch was probably too early, but we thought it would make it easier to get interested parties to work on the code together. OTOH all VCL plugin code is very self-contained, so the early merge doesn't matter that much.

> I noticed that
>support for KF5 was split out and then renamed back to Qt5, but if I
>didn't misread configure.ac KF5 can't really be enabled at the moment.

The idea is to finish a Qt5 only plugin and then derivate the KDE5 plugin classes from it, as it would naturally share a lot of code. Just like the KDE4 plugin derivates from gen / X11 plugin. And the Qt5 plugin could be build and used on multiple platforms as an alternative render path, if someone implements the configure.ac bits.

>I'm a packager and occasional KDE contributor, as of late maintaining
>two small applications. I'm not familiar with the LibreOffice codebase
>but I could probably spare some time if there are things that need a
>helping hand.

If you're interested to get into LibreOffice Qt5 coding, there are the "getting started" pages in the development wiki (https://wiki.documentfoundation.org/Development) with build instructions for all platforms and links to all communication channels, most prominently the #libreoffice-dev IRC channel on freenode. I'll help interested people to get around in VCL + Qt5 area.

And this year a Qt5 GSoC is much more realistic then the "start Qt5 from scratch" idea from the last years :-)

Then there is the "pollution" of the main VCL library with the Qt5 font rendering, which needs some proper abstraction, besides the rendering implementation itself. Currently it just returns some sizes, so LibreOffice looks like the gen plugin without text.

Ultimately there are enough independent todo items for multiple people to work in parallel on the Qt5 codebase. Just needs a bit of coordination.

>Best regards,

Jan-Marek