native-theme

Cross-platform native theme detection and loading for Rust GUI applications.

Overview

native-theme provides a toolkit-agnostic theme data model with 36 semantic color roles, bundled TOML presets, and optional OS theme reading. It gives your Rust GUI application access to consistent, structured theme data regardless of which toolkit you use.

Quick Start

Add the dependency:

cargo add native-theme

Load a preset and access theme fields:

let theme = native_theme::NativeTheme::preset("dracula").unwrap();
let dark = theme.dark.as_ref().unwrap();
let accent = dark.colors.accent.unwrap();
let bg = dark.colors.background.unwrap();
// Convert to f32 for toolkits that use normalized colors
let [r, g, b, a] = accent.to_f32_array();

Preset Workflow

Start with a bundled preset, then layer sparse user overrides on top. The merge() method fills in only the fields present in the overlay, leaving everything else from the base preset intact.

use native_theme::NativeTheme;
let mut theme = NativeTheme::preset("nord").unwrap();
let user_overrides = NativeTheme::from_toml(r##"
name = "My Custom Nord"
[light.colors]
accent = "#ff6600"
"##).unwrap();
theme.merge(&user_overrides);

Runtime Workflow

Use from_system() to read the current OS theme at runtime, with a preset fallback for unsupported platforms:

use native_theme::{from_system, NativeTheme};
let theme = from_system().unwrap_or_else(|_| NativeTheme::preset("default").unwrap());

Platform behavior:

• Linux (KDE): Reads live theme from ~/.config/kdeglobals (requires kde feature).
• Linux (GNOME/other): Returns the bundled Adwaita preset. For live portal data (accent color, dark mode preference, contrast setting), call from_gnome().await directly -- this requires the portal-tokio or portal-async-io feature.
• macOS: Reads system appearance via NSAppearance (requires macos feature).
• Windows: Reads accent colors and system metrics (requires windows feature).
• Other platforms: Returns Error::Unsupported; use the preset fallback.

Toolkit Connectors

Official connector crates handle the full mapping from NativeTheme to toolkit-specific theme types:

• native-theme-iced -- iced toolkit connector with Catalog support for all built-in widget styles
• native-theme-gpui -- gpui + gpui-component toolkit connector

For other toolkits, map NativeTheme fields directly. All color, font, geometry, and spacing fields are public Option<T> values:

let variant = theme.dark.as_ref().unwrap();
let bg = variant.colors.background.unwrap();
let accent = variant.colors.accent.unwrap();
let font = variant.fonts.family.as_deref().unwrap_or("sans-serif");
let radius = variant.geometry.radius.unwrap_or(4.0);

Custom Icon Roles

Apps can define domain-specific icons (e.g., play/pause, git-branch, thermometer) via TOML definitions and the native-theme-build crate. Generated icons integrate with the same loading pipeline as built-in IconRole variants, so they work across all icon sets (Material, Lucide, freedesktop, SF Symbols, Segoe Fluent).

Workflow:

1. Define icons in a TOML file with per-set name mappings and bundled SVGs
2. Add native-theme-build as a build dependency
3. Call generate_icons() in build.rs to generate a Rust enum implementing IconProvider
4. Include the generated code and use load_custom_icon() to load icons at runtime

// build.rs
native_theme_build::generate_icons("icons/icons.toml");

// src/lib.rs
include!(concat!(env!("OUT_DIR"), "/app_icon.rs"));

use native_theme::{load_custom_icon, IconSet};
let icon = load_custom_icon(&AppIcon::PlayPause, IconSet::Material);

See the native-theme-build docs for the full TOML schema, builder API, and DE-aware mapping support.

Feature Flags

By default, no features are enabled. The preset API (NativeTheme::preset(), NativeTheme::from_toml(), NativeTheme::from_file(), NativeTheme::list_presets(), .to_toml()) works without any features.

Available Presets

All presets are embedded at compile time via include_str!() and available through NativeTheme::preset("name"). Each provides both light and dark variants.

Core: default, adwaita, kde-breeze

Platform: windows-11, macos-sonoma, material, ios

Community: catppuccin-latte, catppuccin-frappe, catppuccin-macchiato, catppuccin-mocha, nord, dracula, gruvbox, solarized, tokyo-night, one-dark

Use NativeTheme::list_presets() to get all 17 names programmatically.

TOML Format

Theme files use TOML. All fields are optional -- omit any you don't need. See the NativeTheme::from_toml() documentation for the full format reference.

License

Licensed under either of

• Apache License, Version 2.0
• MIT License
• 0BSD License

at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.