Switch specific Gnome3 applications to GTK Dark Theme, using Devilspie2

readme.md

Watch applications and apply gnome dark themes

This script is for devilspie2. It will match desired windows by class, and then apply the dark theme on them.

Install

Move specific-dark-theme-applications.lua to ~/.config/devilspie2/.

Edit the desiredWindowClasses variable in the file to change which applications this script matches.

specific-dark-theme-applications.lua

-- Script to run on any new window being opened. Used by devilspie2.
-- Summary: Changes the theme of matching windows to their dark theme variant in GTK3.
-- Note: Modify the `desiredWindowClasses` table to filter for certain appliations.
--       You can also see debugging informtion by running with `devilspie2 --debug`
--
-- Author: loklaan


os = require("os")

desiredWindowClasses = {
  Spotify=true,
  Atom=true,
  Terminator=true
}

debug_print("==== Window Details ====");
debug_print()
debug_print("  XID:               " .. get_window_xid())
debug_print("  Window Name:       " .. get_window_name())
debug_print("  Window Class:      " .. get_window_class())
debug_print()

windowId = get_window_xid()
windowClass = get_window_class()
command = "xprop -f _GTK_THEME_VARIANT 8u -set _GTK_THEME_VARIANT 'dark' -id " .. windowId

debug_print()
debug_print("  -- Results -- ")
debug_print()

if (desiredWindowClasses[windowClass]) then
  debug_print("  Match: " .. windowClass .. " ✓");
  debug_print()

  debug_print("  Applying dark theme...");
  debug_print("  Running command: `" .. command .. "`");
  os.execute(command)
  debug_print("  Applied dark theme.");
else
  debug_print("  Match: No match ✖");
end

debug_print()
debug_print()