This guide details the process of creating a custom theme switcher for the Hyprland window manager, leveraging Rofi for user interaction and a custom script to apply changes. The system allows users to select a wallpaper, which then dynamically updates the system's theme, including the wallpaper, terminal colors, and application themes.

System Overview and Setup

The core of this theme switching mechanism is a script, here named wallset, which takes a wallpaper image path as an argument. This script orchestrates several actions:

1. Notification: It sends a notification to the user indicating that the theme is being changed.
2. Wallpaper Application: It sets the chosen wallpaper using swww (Simple Wayland Wallpaper Utility). The command swww img --transition-type <type> --transition-step <steps> --transition-fps <fps> <image_path> is used, allowing for customizable transition effects, steps, and frame rates.
3. Color Generation: It utilizes pywal to generate color schemes based on the selected wallpaper. Specific flags are used with pywal:
   • -n: Skips setting the wallpaper (as it's already handled by swww).
   • -s: Skips changing colors in terminals.
   • -t: Skips changing colors in TTY.
   • -e: Skips reloading xrdb, i3, sway, or polybar. These are omitted as the environment is Wayland.
4. Application Theming:
   • Neovim: An extension, base64-pywal, is used to make Neovim adopt the generated pywal colors. This requires cloning the repository, building it, and adding a configuration line to init.lua. Executing python3 chad.py refreshes colors in open Neovim instances.
   • Spotify: spicetify is employed to adapt Spotify's theme to the pywal colors.
   • Dribbbl: This component is mentioned but deferred for explanation in a separate context.
   • Matugen: This tool, previously explained, generates Material You colors for various applications, including Hyprland, Waybar, and web applications. The configuration for these applications is stored in ~/.config/matugen/config.toml.
5. Wayland Compositor Reload: hyprctl reload is used to refresh Hyprland's configuration.
6. Notification Center Reload: swaync-client -R is executed to reload the Sway Notification Center, which also clears existing notifications.
7. Final Notification: A success message is displayed to the user, confirming that the wallpaper and theme have been applied.

Path Configuration

To ensure the wallset script is accessible system-wide, its directory, ~/lo/bin, must be added to the system's PATH environment variable. For Zsh users, this is done by adding the following line to ~/.zshrc:

export PATH="$HOME/lo/bin:$PATH"

For Bash users, the configuration would be added to ~/.bash_profile.

Additionally, environment variables like TERM (set to kitty in this example) and QT_QPA_PLATFORMTHEME (set to gtk3 for Qt applications) can be configured.

Creating the wallset Backend Script

The wallset script, located in ~/lo/bin, handles the actual theme application.

Argument Handling

The script first checks if a wallpaper image path has been provided as an argument. If not, it displays a usage message: Usage: <program_name> <path_to_image> and exits with a non-zero status code.

if [ -z "$1" ]; then
  echo "Usage: $0 <path_to_image>"
  exit 1
fi

The provided image path is stored in the image variable:

image="$1"

Script Execution Flow

1. Notification:

   notify-send "Changing theme" "Applying new wallpaper..."
   

2. Wallpaper Setting:

   swww img --transition-type Center --transition-step 10 --transition-fps 60 "$image"
   

3. Pywal Color Generation:

   wal -n -s -t -e --theme-name "$image" # Using image name for theme name
   

   Note: The original draft mentions pywal flags -n, -s, -t, -e. The example command includes --theme-name "$image" which is not a standard pywal flag for theme naming in this context, but rather a placeholder for a potential custom theme naming convention.
4. Neovim Refresh:

   python3 ~/.config/nvim/base64-pywal/chad.py
   

5. Spotify Refresh:

   spicetify update
   

6. Matugen Configuration:

   matugen --config ~/.config/matugen/config.toml --wallpaper "$image"
   

7. Hyprland Reload:

   hyprctl reload
   

8. Sway Notification Center Reload:

   swaync-client -R
   

9. Success Notification:

   notify-send "Theme Applied" "Wallpaper and theme updated successfully."
   

Integrating with Rofi

To enable theme switching via Rofi, a separate script, named wallify (or a similar user-chosen name), is created in ~/lo/bin. This script handles the user selection process.

Script Structure

1. Store Current Directory: The script first saves the current working directory to a variable CWD for later use.

   CWD=$(pwd)
   

2. Change to Wallpaper Directory: It then changes the directory to the location of the wallpaper images. If this fails, the script exits.

   cd ~/Pictures/Wallpapers || exit 1
   

3. Set Internal Field Separator: The IFS variable is set to a newline character (\n) to correctly handle filenames with spaces.

   IFS=$'\n'
   

4. User Selection with Rofi: The script uses Rofi to present a list of available wallpapers (JPG and PNG files) to the user.

   selected_wall=$(ls *.jpg *.png | rofi -dmenu -p "Choose Wallpaper: " -i)
   

   • ls *.jpg *.png: Lists all files ending with .jpg or .png in the current directory.
   • rofi -dmenu -p "Choose Wallpaper: " -i: Runs Rofi in dmenu mode, displaying the list of files. -p sets the prompt text, and -i enables case-insensitive matching.
5. Apply Selected Theme: If a wallpaper is selected (i.e., selected_wall is not empty), the wallset backend script is called with the chosen wallpaper path.

   if [ -n "$selected_wall" ]; then
     ~/lo/bin/wallset "$selected_wall"
   fi
   

6. Return to Original Directory: Finally, the script changes back to the original working directory.

   cd "$CWD" || exit 1
   

Making Scripts Executable

Both the wallset and wallify scripts must be made executable using the chmod command:

chmod +x ~/lo/bin/wallset
chmod +x ~/lo/bin/wallify

Keybind Configuration

To trigger the wallify script with a keyboard shortcut, users need to configure a keybind in their Hyprland configuration file (~/.config/hypr/hyprland.conf). For example, to use Super + R:

bind = $mainMod, R, exec, ~/lo/bin/wallify

After setting up these scripts and the keybind, pressing Super + R will launch Rofi, allowing the user to select a wallpaper. Upon selection, the wallset script will execute, applying the chosen wallpaper and updating the system's theme accordingly.