Set Qt theme and font without qt5ct

deleted174

I use the i3 window manager and the qutebrowser web browser. I'd like to configure my preferred font face and size for Qt5 without using any graphical tools such as qt5ct. In particular, I'd like to use some plain text configuration file so that it can be added to my dotfiles git repository. qt5ct's configuration file is not really meant to be read by humans, so I don't like it. When I used GTK I could edit the ~/.config/gtk-3.0/settings.ini file and add a few lines:

[Settings] 
gtk-icon-theme-name = Adwaita 
gtk-theme-name = Adwaita 
gtk-font-name = DejaVu Sans 11

Can I do something similar with the Qt5 toolkit? Thanks.

deleted174

I found out I can create a file called stylesheet.qss with the following content:

* { font-family "Noto Sans"; font-size: 16pt }

Then I can launch qutebrowser as follows:

qutebrowser --qt-arg stylesheet /path/to/stylesheet.qss

This solution seems to be specific to qutebrowser only. How can apply my custom stylesheet to all Qt applications?

mrjj

Hi
I think that has to be supported by your distro - as far as i know the various ways Qt allows it is pr App. Like qt conf and the parameter you used.

If qt5ct works, could you use that to find out where it put the files if that tool can
make it work system-wide ?

You are on ubuntu ?

deleted174

I'm on Gentoo.

mrjj

@fturco said in Set Qt theme and font without qt5ct:

Gentoo

Ok. i dont know that distro but if the qt5ct can do it on that distro , it must mean there is a way to set it somehow.
You could use strace to see if you can find out how its doing it.

deleted174

Unfortunately I don't have any C++/Qt programming skills, so I'm not sure I can understand qt5ct's source code. Learning C++ and Qt is on my todo list anyway, and one of the first real projects could be this one.

Anyway I found another possible workaround:

Configure my favorite fonts in ~/.config/gtk-3.0/settings.ini
Add QT_QPA_PLATFORMTHEME="gtk3" to /etc/env.d/99local
Run env-update
Log out and then log in again

I guess the dev-qt/qtwidgets needs to be built with the gtk USE flag, but I have not tested it without. Probably the gtk USE flag is needed in order to build the /usr/lib64/qt5/plugins/platformthemes/libqgtk3.so file.

mrjj

@fturco
Hi
I did mean to just use strace on qt5ct and see if you could see if it would store any interesting files
in some locations.

Anyway, you solution seems fine also.