oxiui-slint — Slint adapter for OxiUI

oxiui-slint is the Slint backend adapter for OxiUI. It bridges OxiUI's immediate-mode UiCtx API onto the Slint GUI toolkit. The adapter is built around two pieces: SlintCtx, a UiCtx implementation that collects each widget call into an ordered list, and run_slint, a driver that executes a content closure against that context with a supplied theme.

Slint ships a Pure-Rust CPU renderer (renderer-software), so the adapter introduces no GTK/Qt/C++ system widgets. The crate itself is Apache-2.0 and is fully usable with default = [] (collection mode), but enabling the slint feature transitively pulls in the slint crate, which is licensed under GPL-3.0-only OR LicenseRef-Slint-Royalty-free-2.0 OR LicenseRef-Slint-Software-3.0. Downstream consumers must ensure their project's license is compatible with one of those three Slint options. Slint is only compiled when you explicitly request --features slint.

Milestone status: As of M5, run_slint executes the content closure in headless collection mode (no display required) and returns Ok(()), even when the slint feature is enabled. Opening a native window via slint::run_event_loop() is deferred to M6 — see the notes below.

Installation

[dependencies]
# Collection mode only — no Slint dependency, no GPL implications
oxiui-slint = "0.1.2"

# Enable Slint rendering (pulls in the GPL/royalty-free/commercial slint crate)
oxiui-slint = { version = "0.1.2", features = ["slint"] }

Quick Start

Collection mode (no slint feature, fully testable)

use oxiui_slint::SlintCtx;
use oxiui_core::UiCtx;

let mut ctx = SlintCtx::default();
ctx.heading("My Window");
ctx.label("Status: ok");
let resp = ctx.button("Continue");

assert_eq!(ctx.items.len(), 3);
assert_eq!(ctx.items[0], "heading:My Window");
assert!(!resp.clicked);

Driving a content closure with a theme

use oxiui_slint::run_slint;
use oxiui_theme::cooljapan_dark;

run_slint(&*cooljapan_dark(), |ui| {
    ui.heading("Hello from Slint");
    ui.label("OxiUI + slint backend");
})
.expect("slint run failed");

API Overview

Types

Functions

SlintCtx as a UiCtx

SlintCtx implements the three required UiCtx methods. All other UiCtx widget methods (slider, checkbox, dropdown, text_input, …) fall back to their default trait implementations, which report supported == false so callers can detect non-support and degrade gracefully.

The items entries use the format "<kind>:<text>" (e.g. "label:Hello", "button:Quit"), letting headless tests assert on the exact widget sequence without opening a window.

Feature Flags

Errors

run_slint returns Result<(), oxiui_core::UiError>. In M5 it is always Ok(()). From M6 onward it will return UiError::Backend if Slint's event loop reports an error. UiError is #[non_exhaustive]; see oxiui-core for the full variant list.

Palette mapping note

Slint 1.16.1 exposes slint::Color::from_argb_u8(a, r, g, b) and per-component accessors (available under renderer-software, no backend-winit needed). However, Slint's global style/theme API in 1.16.1 does not expose a pluggable external-palette injection seam: the StyleMetrics struct is set internally and is not public. The palette argument to run_slint is therefore available for downstream consumers who build slint::Color values directly in their own components; it is not automatically applied to Slint's global style in M5. Full palette mapping is planned for M6 once a public API seam is confirmed.

Related Crates

License

Apache-2.0 — COOLJAPAN OU (Team Kitasan)