Neony

Reactive desktop UI framework for Python, built on LumiView.

中文文档 · API Reference (EN) · API 参考 (中文)

Overview

Neony renders a reactive DOM in a native window. You compose your UI from Python objects — components, layouts, styles — and Neony diff-updates the browser DOM automatically. No HTML, no JavaScript, no CSS strings.

It builds on LumiView, which uses the same Rust tao/wry webview stack as Tauri.

• Pure Python API — components, layouts and events, no need for non-python codes
• Same stack as Tauri — Rust tao/wry webviews via LumiView
• 3 theme presets — dark / light / deep-blue via CSS custom properties
• (Optional) Frosted glass — translucent surfaces with backdrop blur
• Custom window chrome — frameless, transparent, custom TitleBar
• (Supported platform only) Native window effects — blur / acrylic / mica materials

Installation

pip install neony

Requires Python 3.11+ and the platform WebView stack (WebKitGTK on Linux, WebView2 on Windows, WKWebView on macOS).

Quick Start

from neony.application import Page, launch
from neony.application.elements import Button, Heading, Text, VStack

counter = Button("Click me")


async def on_click(event) -> None:
    counter.label = "Clicked!"


counter.on_click(on_click)

page = Page(gap="16px").add(
    VStack(
        Heading("Hello, Neony", level=1),
        Text("Build desktop UI in pure Python.", role="secondary"),
        counter,
        gap="12px",
    )
)

launch(page, title="My App", width=480, height=360, devtools=True)

Components

Import from neony.application.elements.

All components share a fluent, chainable API — see the API reference for usage.

Window Features

• Frameless custom titlebar — set decorations=False, add a TitleBar, and drag / minimize / maximize / close all work automatically. See docs/api.en.md and the test_custom_window.py demo.
• Transparent windows & native effects — transparent=True plus apply_blur(), apply_acrylic(), apply_mica(). See test_transparent_panel.py.
• Programmatic window control — set_title(), set_size(), minimize(), toggle_maximize(), close(), … all on NeonApplication, with window_index=0 for multi-window apps.
• Multi-window — run(*pages) opens one window per page, all sharing one event loop and app.state. launch([...]) accepts a list. See test_multi_window.py.

Theming

Three built-in presets — DARK (default), LIGHT, DEEP_BLUE — exposed as CSS custom properties on :root, so a theme switch redraws the whole UI with zero DOM diff. See the API reference for switching and custom themes.

Demos

Run from the repository root:

uv run test_gallery.py

Development

This project uses uv as the environment manager and runner.

uv sync --group dev   # install dependencies (incl. dev tools)

uv run test_gallery.py            # run a demo
uv run pytest -q                  # run the test suite
uv run ruff check .               # lint
uv run ruff format --check .      # format check
uv run pyrefly check              # type check

License

LGPL-3.0-or-later © HarcicYang