KDE Day/Night Mode Automator

Automatically switches your KDE Plasma Global Theme between a light and dark variant based on the time of day.

How It Works

This project uses a simple shell script that is executed periodically by a systemd user timer.

• kde-day-night.sh: The core script that checks the current time and applies the appropriate KDE Global Theme using lookandfeeltool.
• kde-day-night.service: A systemd user service that runs the shell script.
• kde-day-night.timer: A systemd user timer that triggers the service every 15 minutes.

Remember:

• if you use custome theme or setup this tool may not be a better choice

Prerequisites

• A Linux distribution with KDE Plasma 5.
• systemd (used by most modern Linux distributions).
• Your desired light and dark Global Themes must be installed.

Installation

1. Save all the project files (kde-day-night.sh, install.sh, etc.) into a single directory.

2. Open a terminal and navigate into that directory.

3. Run the installer: The installer will copy the files to the correct locations (~/.config/) and enable the systemd timer for your user.

   bash ./install.sh

That's it! The script will now run automatically.

Configuration

If you want to change the times or the themes, you can edit the configuration section at the top of the script:

~/.config/kde-day-night/kde-day-night.sh

# --- Configuration ---
# Set the times for day and night mode switching (24-hour format HH:MM)
DAY_START="07:00"
NIGHT_START="19:00"

# Set the names of your preferred light and dark global themes.
# You can find available themes in System Settings > Appearance > Global Theme.
# The names are often package-like, e.g., "org.kde.breeze.desktop" or "org.kde.breezedark.desktop"
LIGHT_THEME="org.kde.breeze.desktop"
DARK_THEME="org.kde.breezedark.desktop"
# --- End Configuration ---

Finding Theme Names

You can find the internal names of your installed Global Themes by looking in System Settings > Appearance > Global Theme or by listing the contents of /usr/share/plasma/look-and-feel/. The directory names correspond to the theme names (e.g., org.kde.breezedark.desktop).

Usage

The script runs automatically. To manually trigger a theme check, you can run:

systemctl --user start kde-day-night.service

Checking Status and Logs

To check the status of the timer: systemctl --user status kde-day-night.timer

To view the logs from the script: journalctl --user -u kde-day-night.service

Uninstallation

To remove the automation, simply run these commands:

systemctl --user stop kde-day-night.timer
systemctl --user disable kde-day-night.timer
rm ~/.config/systemd/user/kde-day-night.{service,timer}
rm -r ~/.config/kde-day-night
systemctl --user daemon-reload