hjkl-css-gui

Renamed from hjkl-css-floem 2026-05-18 to match the -gui floem-adapter convention used elsewhere in hjkl (e.g. hjkl-editor-gui).

Adapter that maps a hjkl-css Stylesheet onto floem views via an extension trait.

Part of the hjkl monorepo — a vim-modal editor in Rust.

Usage

Flat call (no combinator context)

use hjkl_css::parse;
use hjkl_css_gui::ViewCssExt;

let sheet = parse(r#"
    label { color: #c0caf5; padding: 4px 8px; }
    label.prompt { color: #21d1d3; }
    .row:hover { background-color: rgba(33, 209, 211, 0.18); }
"#).unwrap();

let view = floem::views::label(|| "hello")
    .css(&sheet, "label", &["prompt"]);

.css(sheet, element, classes) resolves the cascade for the base state plus every supported pseudo (:hover, :focus, :active, :disabled, :selected) and merges the resulting property bags into a single floem Style block, delegating per-state behaviour to floem's own .hover() / .focus() / etc. chain.

Context-aware call (combinator selectors)

Use .css_in(...) when the view lives inside a hierarchy and descendant ( ), child (>), adjacent-sibling (+), or general-sibling (~) selectors need to match:

use hjkl_css::{Node, parse};
use hjkl_css_gui::ViewCssExt;

let sheet = parse(".row .label { color: #fff; }").unwrap();

let target = Node { element: "span", classes: &["label"] };
let ancestors = [Node { element: "div", classes: &["row"] }];

let view = floem::views::label(|| "hello")
    .css_in(&sheet, target, &ancestors, &[]);

ancestors is root→parent (exclusive of target); prev_siblings is oldest→immediately-preceding sibling (exclusive of target).

Supported properties (hjkl-css v0.4.0)

CSS property	Notes
`color`
`background-color`
`width`, `height`	`auto` supported
`padding`	1..=4 length shorthand
`margin`	1..=4 length/auto shorthand; `auto` and mixed `4px auto` both work
`gap`, `row-gap`, `column-gap`
`display`	`flex`, `block`, `none`
`flex-direction`	`row`, `column`, `row-reverse`, `column-reverse`
`align-items`	`start`, `end`, `center`, `stretch`, `baseline`
`justify-content`	`start`, `end`, `center`, `space-between`, `space-around`, `space-evenly`
`flex-grow`, `flex-shrink`	unitless number
`flex-basis`	length or `auto`
`border`	shorthand — sets all four sides + `border-color`
`border-top/right/bottom/left`	per-side shorthand
`border-width`	1..=4 side shorthand (px only)
`border-color`
`border-top-color`	collapses to global brush — floem 0.2 has no per-side color setter
`border-right-color`	collapses to global brush — floem 0.2 has no per-side color setter
`border-bottom-color`	collapses to global brush — floem 0.2 has no per-side color setter
`border-left-color`	collapses to global brush — floem 0.2 has no per-side color setter
`border-radius`	first value used as uniform radius; floem 0.2 has no per-corner API
`outline`	width + color forwarded via `outline` + `outline_color`
`font-size`	px only — floem 0.2 `font_size` takes `Px`
`font-weight`	numeric (e.g. `700`) or keyword (`normal`, `bold`)
`font-style`	`normal`, `italic`, `oblique`
`font-family`	first family name used; floem 0.2 accepts one `String`
`line-height`	unitless multiplier only; px variant silently skipped
`text-align`	gap: floem 0.2 has no `text_align` setter — parsed but not forwarded

Unknown properties are silently skipped per the CSS lenient-parsing posture.

Selectors

Supported via hjkl-css v0.4.0:

Type selectors: label
Class selectors: .prompt
Pseudo-class selectors: :hover, :focus, :active, :disabled, :selected
Compound selectors: button.primary:hover
Combinators (require .css_in(...)): descendant , child >, adjacent-sibling +, general-sibling ~
Selector lists: label, .btn { … }

Documentation

docs.rs/hjkl-css-gui

Contributing

See the monorepo CONTRIBUTING guide.

License

MIT — see LICENSE.

hjkl-css-gui 0.29.0