Ubuntu Quick User Switcher

A modern GTK4/Libadwaita application for fast user switching on Ubuntu and other Linux distributions. Switch between user accounts without logging out, preserving your current session and applications.

Features

🚀 Intelligent Session Switching

• Direct switching to users with active sessions (no password required)
• Preserves your current session and running applications
• Smart detection of existing user sessions using systemd loginctl

👤 Modern User Interface

• Clean GTK4/Libadwaita design following GNOME HIG
• Profile picture support from AccountsService and ~/.face
• User-friendly confirmation dialogs and status messages

⚡ Multiple Switching Methods

• loginctl activate - Direct session activation (fastest)
• dm-tool switch-to-user - LightDM integration
• GDM D-Bus interface - Native GNOME support
• Fallback to login screen for new users

🔒 Session Preservation

• Your current session stays active in the background
• All applications continue running
• Return to your work exactly where you left off

Installation

Quick Install

git clone https://github.com/ecappa/ubuntuQuickUserSwitcher.git
cd ubuntuQuickUserSwitcher
chmod +x install.sh
./install.sh

Manual Installation

# Install system dependencies
sudo apt update
sudo apt install -y python3-gi python3-gi-cairo gir1.2-gtk-4.0 libadwaita-1-dev gir1.2-adw-1

# Install Python dependencies
pip3 install -r requirements.txt

# Make executable
chmod +x quick_switch.py

# Create desktop shortcut (optional)
cp quick-switch.desktop ~/.local/share/applications/

Usage

Run from Command Line

./quick_switch.py

Run from Applications Menu

After installation, search for "Quick Switch" in your applications menu.

How It Works

1. Launch the application
2. Select a user from the list
3. Confirm the switch
4. The app will:
   • Switch directly to active sessions (instant)
   • Open login screen for new users
   • Preserve your current session

Requirements

• OS: Ubuntu 20.04+ (or any Linux with systemd)
• Python: 3.8+
• Desktop: GTK4-compatible environment (GNOME, etc.)
• Display Manager: GDM, LightDM, or compatible

Technical Details

Session Detection

• Uses loginctl list-sessions to detect active user sessions
• Parses session state, user ID, and session ID
• Intelligently chooses switching method based on session status

Switching Methods (Priority Order)

1. loginctl activate [session-id] - For existing sessions
2. dm-tool switch-to-user [username] - LightDM direct switching
3. GDM D-Bus interface - Native GNOME switching
4. dm-tool switch-to-greeter - Fallback to login screen

Profile Pictures

Searches for user avatars in:

1. /var/lib/AccountsService/icons/[username]
2. ~/.face
3. ~/.face.{jpg,jpeg,png,gif}

Troubleshooting

User Switching Doesn't Work

• Ensure your display manager supports user switching
• Check that systemd-logind is running: systemctl status systemd-logind
• Verify loginctl works: loginctl list-sessions

Permission Issues

• Make sure the script is executable: chmod +x quick_switch.py
• Check that your user has access to loginctl commands

Display Issues

• Ensure GTK4 and Libadwaita are installed
• Update your system: sudo apt update && sudo apt upgrade

Development

Project Structure

• quick_switch.py - Main application
• requirements.txt - Python dependencies
• install.sh - Installation script
• quick-switch.desktop - Desktop entry
• CLAUDE.md - Development documentation

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Test on Ubuntu/GNOME
5. Submit a pull request

License

This project is open source. Feel free to use, modify, and distribute.

Credits

Developed with assistance from Claude Code for modern Ubuntu user switching needs.