Add gtk3 reload in reload.py from wpg

This requires a theme like deviantfero's FlatColor to change gtk3 color theme
on reload. See https://github.com/deviantfero/wpgtk-templates/tree/master/FlatColor. Add the base files to the user template folder. Use the -g command line parameter to use this function.

pywal/__main__.py

@@ -112,6 +112,9 @@ def get_args():
     arg.add_argument("-e", action="store_true",
                      help="Skip reloading gtk/xrdb/i3/sway/polybar")
 
+    arg.add_argument("-g", action="store_true",
+                     help="Reload the gtk3 theme")
+
     return arg
 
 
@@ -216,6 +219,9 @@ def parse_args(parser):
 
     if not args.e:
         reload.gtk()
+    
+    if args.g:
+        reload.gtk3()
 
 
 def main():

pywal/reload.py

@@ -6,7 +6,7 @@ import os
 import shutil
 import subprocess
 
-from .settings import CACHE_DIR, MODULE_DIR, OS
+from .settings import CACHE_DIR, XDG_CONF_DIR, MODULE_DIR, OS
 from . import util
 
 
@@ -30,7 +30,7 @@ def xrdb(xrdb_files=None):
 
 
 def gtk():
-    """Reload GTK theme on the fly."""
+    """Reload GTK2 theme on the fly."""
     # Here we call a Python 2 script to reload the GTK themes.
     # This is done because the Python 3 GTK/Gdk libraries don't
     # provide a way of doing this.
@@ -40,6 +40,84 @@ def gtk():
 
     else:
         logging.warning("GTK2 reload support requires Python 2.")
+        
+def gtk3():
+    """Reload GTK3 theme on the fly, requires a theme that enables styling via gtk.css"""
+    settings_ini = os.path.join(XDG_CONF_DIR, "gtk-3.0", "settings.ini")
+
+    # Multiple backends available to set, xfsettings for xfce,
+    # then gsd-settings in gnome, gsettings for everything else
+    refresh_gsettings = (
+        "gsettings set org.gnome.desktop.interface "
+        "gtk-theme '' && sleep 0.1 && gsettings set "
+        "org.gnome.desktop.interface gtk-theme '{}'"
+    )
+
+    refresh_xfsettings = (
+        "xfconf-query -c xsettings -p /Net/ThemeName -s"
+        " '' && sleep 0.1 && xfconf-query -c xsettings -p"
+        " /Net/ThemeName -s '{}'"
+    )
+
+    if shutil.which("gsettings"):
+        cmd = ["gsettings", "get", "org.gnome.desktop.interface", "gtk-theme"]
+        gsettings_theme = subprocess.Popen(
+            cmd,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.DEVNULL
+        ).communicate()[0].decode().strip("' \n")
+
+    xfsettings_theme = None
+    if shutil.which("xfconf-query"):
+        cmd = ["xfconf-query", "-c", "xsettings", "-p", "/Net/ThemeName"]
+        xfsettings_theme = subprocess.Popen(
+            cmd,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.DEVNULL
+        ).communicate()[0].decode().strip("' \n")
+
+    if util.get_pid("gsd-settings") and gsettings_theme:
+        subprocess.Popen(refresh_gsettings.format(gsettings_theme), shell=True)
+        logging.info("Reloaded %s theme via gsd-settings" % gsettings_theme)
+
+    elif util.get_pid("xfsettingsd") and xfsettings_theme:
+        subprocess.Popen(refresh_xfsettings, shell=True)
+        logging.info("reloaded %s theme via xfsettingsd" % xfsettings_theme)
+
+    # no settings daemon is running.
+    # So GTK is getting theme info from gtkrc file
+    # using xsettingd to set the same theme (parsing it from gtkrc)
+    elif shutil.which("xsettingsd") and os.path.isfile(settings_ini):
+        gtkrc = configparser.ConfigParser()
+        gtkrc.read(settings_ini)
+
+        if gtkrc["Settings"]:
+            theme = gtkrc["Settings"].get("gtk-theme-name", "FlatColor")
+            fd, path = tempfile.mkstemp()
+
+            try:
+                with os.fdopen(fd, "w+") as tmp:
+                    tmp.write('Net/ThemeName "' + theme + '"\n')
+                    tmp.close()
+                    util.silent_call([
+                        "timeout", "0.2s", "xsettingsd", "-c", path
+                    ])
+                logging.info(
+                    "reloaded %s from settings.ini using xsettingsd"
+                    % theme
+                )
+            finally:
+                os.remove(path)
+
+    # The system has no known settings daemon installed,
+    # but dconf gtk-theme exists, just refreshing its theme
+    # Because user might be using unknown settings daemon
+    elif shutil.which("gsettings") and gsettings_theme:
+        subprocess.Popen(refresh_gsettings.format(gsettings_theme), shell=True)
+        logging.warning(
+            "No settings daemon found, just refreshing %s theme from gsettings"
+            % gsettings_theme
+        )
 
 
 def i3():