[SOLVED] XFCE4 and font setup for Qt5 application

[leonid]

Hello!

After upgrade my qt-creator was up to 3.x, so it is build with Qt5. But fonts in it (menus and dialogs) is differ than in other apps (Qt4 and gtk for example). QtConfig program does not work with Qt5.

How could I setup fonts for Qt5?
_________________
Leonid Kolesnik

[SpaceToast]

Qt5 does not ship with qtconfig, and rather decides what to do based on the desktop environment you are using.

This is the behavior:

• Under Plasma 5: use selected Qt style (systemsettings5)
  
• Under KDE4: Oxygen (if available), then Fusion
  
• Cinnamon, Gnome, MATE, LXDE, Xfce: GTK+ (QGtkStyle)
  
• Other: Fusion
  

You can change what it detects by exporting QT_QPA_PLATFORMTHEME in your profile.
You could add USE=gtkstyle to qtgui, rebuild it, export QT_QPA_PLATFORMTHEME to gtk, and it'll then mimic your GTK config.

There is also apparently a tool named qt5ct which mimics qtconfig, but for qt5 (required to export QT_QPA_PLATFORMTHEME to qt5ct). This is however not in-tree, but you are free to experiment with it.

[leonid]

I reopen this topic as no decision found for one year.

It was acceptable while there was not many apps with qt5. But now its count increases.

So, one more time:

I use XFCE 4.12
I have some apps using qt (qt-creator (uses qt5), clementine (uses qt4) and others) and some apps from KDE (okular, for example).

qtgui installed with gtkstyle flag enabled.
QT_QPA_PLATFORMTHEME=gtk (in /etc/inveronment)

BUT:

1. Fonts in XFCE apps is ok
2. Fonts in qt4 and KDE apps is ok and the same as in XFCE apps
3. Fonts in qt5 apps is different and ugly.

No working answers in net found.

My example at screenshot:
https://www.modbus4qt.ru/download/external/img.png

Qt creator is one qt5 apps.
_________________
Leonid Kolesnik

[leonid]

Discovering...

When I changed font in XFCE control panel it was changed and in qt5 apps.

So it is different rendering only

PS And qt5ct has no effect for me. Or I do something wrong.
_________________
Leonid Kolesnik

[mir3x]

You could in theory install lxqt, configure fonts, theme and rest.

Then export environment variable QT_QPA_PLATFORMTHEME=lxqt in your xfce.
( then u might remove all lxqt packages except lxqt-qtplugin)
EIDT: u sure its export QT_QPA_PLATFORMTHEME=gtk
and not export QT_QPA_PLATFORMTHEME=gtk2 ??
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Sent from Windows

[leonid]

Sure.

I'll try use lxqt
_________________
Leonid Kolesnik

[leonid]

It uses gtk style. But it looks like is does not use fontconfig.
_________________
Leonid Kolesnik

[leonid]

The problem was in droid fonts. When I've selected any other fonts all became good.

For now for result:

1. USE flag for qtqui & qtwidgets: gtkstyle
2. QT_QPA_PKATFORMTHEME=gtk in /etc/invironment
3. Set up ubuntu font for default in XFCE settings

Fot Qt4 apps setup ubuntu font in Qt4 configuration tool

Thats all.
_________________
Leonid Kolesnik