Rasi vs underlying CSS features?

[tom-gora]

For my usecase I was thrilled to find out GTK CSS standard provides an option for index-based styling with functional pseudoclasses like :nth-child() . Unfortunately this does not work in syntax for rasi as it seems. Is it not that theme file transpiles under the hood to regular GTK CSS? Or is it read and interpreted by rofi directly? I guess what I ask is: is this something that would require implementation or is there a way to write config file to get the styling to apply?

[tom-gora]

Nevermind. Found a workaround -markup-rows flag allows me to inline style in markup per line :)

EDIT: This script is written for wayland [hyprland] and uses hyprpicker and pastel packages as deps and wl-copy/paste for clipboard interactions.
These can I think easily be replaced for any other input method outputting a valid hex color code, (heck pastel itself has a picker function, only it spawns an unnecessary gui after picking instead of just returning color value) and any other cliboard managing package like xclip would also be easily swappable.

[tom-gora]

Example usage of how I did achieve per-line styling. Hope it helps if anyone is looking for answers and bumps into this thread :)

RofiColorShades.sh

#!/bin/bash

# Rofi menu for color shades

iDIR="$HOME/.config/swaync/images"
pastel=$(which pastel)
hyprpicker=$(which hyprpicker)
missing_deps=()

if [[ -z "$pastel" ]]; then
	missing_deps+=("pastel")
fi
if [[ -z "$hyprpicker" ]]; then
	missing_deps+=("hyprpicker")
fi

if [[ ${#missing_deps[@]} -ne 0 ]]; then
	notify-send -t 4000 -i "$iDIR/rofi-error.svg" "Rofi Error" "Dependencies not found: \
    ${missing_deps[*]} \
    Please install them first."
	exit 1
fi

final_validate_color_from_pastel() {
	local line="$1"
	[[ "$line" =~ ^#[0-9A-Fa-f]{3,8}$ ]]
}

main() {
	SOURCE_COLOR="$(wl-paste)"
	pastel color "$SOURCE_COLOR" >/dev/null 2>&1
	EXIT_CODE=$?

	if [[ $EXIT_CODE -ne 0 ]]; then
		SOURCE_COLOR="$(hyprpicker)"
	fi
	FROM_DARK=$(pastel gradient --number=14 000000 "$SOURCE_COLOR" | pastel format hex | sed '$d')
	INTO_LIGHT=$(pastel gradient --number=14 "$SOURCE_COLOR" ffffff | pastel format hex)
	FULL_GRADIENT_LIST=$(echo -e "$FROM_DARK\n""$INTO_LIGHT")
	declare -a TEMPLATE
	while IFS= read -r line; do

		if ! final_validate_color_from_pastel "$line"; then
			notify-send -t 4000 -i "$iDIR/rofi-error.svg" "Rofi Error" "Invalid color value encountered. Try again."
			exit 1
		fi
		
		templated_line="<span bgcolor='$line' fgcolor='$line'>XXXXXXXXXXXXXXXXXXXX</span>    <span>$line</span>"
		TEMPLATE+=("$templated_line")
	done <<<"$FULL_GRADIENT_LIST"

	MARKUP=$(printf "%s\n" "${TEMPLATE[@]}")
	echo "$MARKUP" | rofi -dmenu -config ~/.config/rofi/config-shades.rasi -markup-rows | wl-copy

}
main

[DaveDavenport]

Might be good to mention this script of for wayland! (hyprpicker).

[tom-gora]

Might be good to mention this script of for wayland! (hyprpicker).

Thanks. I added a few words on dependencies since I already declared willing to be helpful let's do it proper.

[DaveDavenport]

For people finding this discussion thread:

Is it not that theme file transpiles under the hood to regular GTK CSS

Rofi does not support CSS, it has it own language and parser that is slightly inspired by it, in the hope its is easier for people to make modifications to themes. (still debatable this was one of my worst design choices..)

Rofi also does not use or depend on GTK for any of its rendering. Rendering is done using cairo.

[tom-gora]

On one hand yeah on the other it is a pitfall that gtk css is it's own standard very divergent from the web baseline in my view. All in all keeping your own way for declaring styles just adds to existing mess a little bit but as we can see for the willing there are workarounds ;)
Thank you for explanation!