GUI toolkits

GTK

• GKT is a widget toolkit for building GUI applications
• GTK will default to the Wayland backend
• Override it to Xwayland by modifying the environment variable: GDK_BACKEND=x11

Configuration

GTK3

# Force GTK3 dark mode using environment variable (not recommended)
GTK_THEME="Adwaita:dark" nautilus

# /etc/gtk-3.0/settings.ini
# ~/.config/gtk-3.0/settings.ini
[Settings]
gtk-application-prefer-dark-theme = true

GTK4

gsettings set \
  org.gnome.desktop.interface \
  color-scheme prefer-dark

QT

• QT is a widget toolkit for building GUI applications

• To enable Wayland support in Qt 5 or 6, install the qt5-wayland or qt6-wayland package

• QT6: qt6-base

• QT5: qt5-base
• QT4: qt4 (aur)
• QT3: qt3 (aur)

Configuration-

# Set default style/theme
QT_STYLE_OVERRIDE=adwaita-dark
QT_STYLE_OVERRIDE=kvantum

# Set default platform theme
QT_QPA_PLATFORMTHEME=gtk2 # QGtkStyle
QT_QPA_PLATFORMTHEME=gnome # QGnomePlatform
QT_QPA_PLATFORMTHEME=qt5ct

QT_WAYLAND_DECORATION=adwaita # QAdwaitaDecorations

Decoration plugin

• Decoration plugin

• QGtkStyle

• QGnomePlatform (deprecated)
• QAdwaitaDecorations (under development)