Setting up individual themes for Kvantum

Configuring Individual Themes in Kvantum Manager

To configure individual themes in Kvantum Manager, you need to edit the configuration file ~/.config/Kvantum/kvantum.kvconfig, using the [Applications] section to assign different themes to different applications. This will allow you to use Arc for some Qt applications and Arc-Dark for others, solving the problem of applying the same theme to all applications simultaneously.

Table of Contents

• Understanding the Problem and Solution
• Configuring the Configuration File
• Example Configuration for Arc and Arc-Dark
• Additional Configuration Methods
• Troubleshooting
• Conclusions

Understanding the Problem and Solution

The current situation where a single Kvantum theme is applied to all Qt applications simultaneously is standard system behavior. However, Kvantum provides a flexible mechanism for individually assigning themes to different applications through the configuration file.

As noted in the Kvantum documentation, the solution involves using the [Applications] section in the ~/.config/Kvantum/kvantum.kvconfig file. This approach allows you to:

• Assign different themes to different Qt applications
• Create a unique visual experience for various programs
• Solve the problem of applying the same theme to all applications

Configuring the Configuration File

To get started, you need to find and edit the main Kvantum configuration file:

Step 1: Locating the Configuration File

The Kvantum configuration file is typically located at:

~/.config/Kvantum/kvantum.kvconfig

If this file doesn’t exist, you can create it manually or through Kvantum Manager.

Step 2: Configuration File Structure

The basic structure of the file looks like this:

[General]
theme=ACTIVE_THEME

[Applications]
THEME1=app1, app2
THEME2=app3

Where:

• theme=ACTIVE_THEME specifies the default active theme
• The [Applications] section contains rules for individual applications
• THEME1 is the name of the theme to be applied to the specified applications

Step 3: Editing the File

To edit the file, you can use any text editor, for example:

nano ~/.config/Kvantum/kvantum.kvconfig

Example Configuration for Arc and Arc-Dark

To solve your specific task of using Arc for kvantum and Arc-Dark for kvantum-dark, you need to configure the configuration file as follows:

Working Configuration Example

[General]
theme=Arc

[Applications]
Arc-Dark=konsole, kate, dolphin

This configuration:

• Sets Arc as the default theme
• Applies Arc-Dark only to konsole, kate, and dolphin applications

Identifying Applications

To identify specific applications that should use Arc-Dark, use their executable names. Some common Qt applications:

Full Example for Your Goal

[General]
theme=Arc

[Applications]
Arc-Dark=konsole, kate, dolphin, kwrite, okular

Additional Configuration Methods

Using Kvantum Manager

For more convenient configuration, you can use the Kvantum Manager graphical interface:

1. Launch Kvantum Manager from the application menu
2. Go to the “Change/Delete Theme” section
3. Select the desired theme and click “Use this theme”
4. For fine-tuning, use the “Configure Active Theme” section

Command Line

For more advanced configuration, you can use the command line:

# View available themes
ls -la ~/.config/Kvantum/

# Apply theme for specific application
export QT_QPA_PLATFORMTHEME=qt5ct
export QT_STYLE_OVERRIDE=kvantum

Integration with System Settings

Don’t forget to check KDE system settings:

1. Open “System Settings”
2. Go to “Application Style”
3. Make sure Kvantum is selected as the widget theme
4. Verify that the appropriate color scheme is set in “Colors”

Troubleshooting

Problem: Theme Not Applied

If the theme is not being applied, check:

1. Correctness of theme file paths
2. Presence of required packages:
   bash

   # For Arch Linux
   sudo pacman -S kvantum-theme-arc
   
   # For Ubuntu/Debian
   sudo apt install kvantum-theme-arc
   

3. File permissions for the configuration file

Problem: Conflict with GTK Themes

If conflicts arise between Qt and GTK themes:

1. Ensure GTK themes are properly configured
2. Check environment variables:
   bash

   echo $QT_QPA_PLATFORMTHEME
   echo $QT_STYLE_OVERRIDE
   

Problem: Kvantum Cache

Sometimes you need to clear the Kvantum cache:

rm -rf ~/.cache/Kvantum/

Conclusions

Configuring individual themes for Kvantum Manager is a powerful mechanism for creating a custom appearance for different Qt applications. The main steps to achieve your goal are:

1. Edit the ~/.config/Kvantum/kvantum.kvconfig file
2. Use the [Applications] section to assign Arc-Dark to specific applications
3. Ensure all required themes are installed on your system
4. Check KDE system settings and Kvantum Manager

This approach will allow you to use Arc for most applications while using Arc-Dark for those where a dark theme is preferable, solving the problem of applying the same theme to all programs.

Sources

1. Kvantum Theme Configuration Documentation
2. Kvantum Manager Usage Guide
3. Arc KDE Theme Installation Guide
4. Kvantum Installation Instructions
5. Arch Linux Kvantum Theme Configuration
6. Arc KDE Theme on KDE Store