Linux Mint Cinnamon Dark Mode

crontab

# Every day at 07:00 disable dark mode.
0 7 * * * /bin/sh /home/michael/.local/bin/dark-mode.sh false

# Every day at 21:00 enable dark mode.
0 21 * * * /bin/sh /home/michael/.local/bin/dark-mode.sh true

dark-mode.sh

#!/bin/sh
# Changes the theme to use a dark variant and attempt to update applications.
# This script doesn't completely work - some programs may need to be restarted to see the change.
# Usage: dark-mode.sh [true|false]

# Name of the theme to use.
# The dark variant should be "NAME-Dark"
theme="Arc"

# Check input, default to enable dark mode.
action="$1"
test -z "$action" && action=true

if [ "$action" = 'true' ]; then
  # Switch to dark theme.
  SEARCH=gtk-application-prefer-dark-theme=false
  REPLACE=gtk-application-prefer-dark-theme=true
  theme="$theme-Dark"
else
  # Switch to light theme.
  SEARCH=gtk-application-prefer-dark-theme=true
  REPLACE=gtk-application-prefer-dark-theme=false
fi

# Let applications know to use dark theme.
/bin/sed -i 's/'$SEARCH'/'$REPLACE'/g' /home/michael/.config/gtk-3.0/settings.ini

# Set Gnome, Cinnamon, and GTK settings.
/usr/bin/gsettings set org.cinnamon.desktop.interface gtk-theme "$theme"
/usr/bin/gsettings set org.cinnamon.desktop.interface gtk-color-scheme ""
/usr/bin/gsettings set org.cinnamon.desktop.wm.preferences theme "$theme"
/usr/bin/gsettings set org.cinnamon.theme name "$theme"
/usr/bin/gsettings set org.gnome.desktop.interface gtk-theme "$theme"
/usr/bin/gsettings set org.gnome.desktop.interface gtk-color-scheme ""
/usr/bin/gsettings set org.gnome.desktop.wm.preferences theme "$theme"
/usr/bin/gconftool --type=string --set /desktop/cinnamon/windows/theme "$theme"

# Refresh GTK applications.
# https://crunchbang.org/forums/viewtopic.php?pid=428525#p428525
python - <<END
import gtk

events=gtk.gdk.Event(gtk.gdk.CLIENT_EVENT)
data=gtk.gdk.atom_intern("_GTK_READ_RCFILES", False)
events.data_format=8
events.send_event=True
events.message_type=data
events.send_clientmessage_toall()

END