Lace

Advanced docking system for PySide6 — a feature-rich, themeable widget layout framework for building professional Qt desktop applications in Python.

Version: 0.4.0

Table of Contents

• Features
• Quick Start
• Screenshots
• Architecture Overview
• Documentation
• Contributing
• License

Features

🪑 Docking & Layout

• Multi-area docking — Dock widgets to left, right, top, bottom, or center regions within a window
• Tabbed dock areas — Multiple widgets share a single dock area as tabs, with full tab management (reorder, close, float)
• Floating windows — Detach any dock widget into its own top-level window; drag it back to dock
• Drag-and-drop layout — Intuitive resize, re-order, and re-dock via visual drop indicators
• Nested splitters — Arbitrary nesting of horizontal and vertical split panes
• Maximize/restore — Expand any dock area to fill its container

📌 Sidebars

• Auto-hide panels — VS Code-style slide-out sidebars that appear on hover
• Pinned widgets — Pin dock widgets to sidebars with visual tab buttons
• Notification badges — Numerical or symbolic badges on sidebar tabs
• Configurable focus behavior — Choose whether sidebars steal keyboard focus
• Drag to detach — Tear pinned widgets out of sidebars back into the main layout

🎨 Theming

• 14 built-in themes — Dark, light, midnight, warm, nordic, monokai, neutral, tokyo_night, catppuccin, dracula, solarized_dark/light, and cyberpunk_neon
• Declarative ThemeSpec — Define custom themes with color palettes and geometrical tokens (corner radius, border width, title height, tab radius, content margin, etc.)
• Reactive borders — Active dock area shows a vibrant focus border; inactive areas show a subtle neutral border
• OS auto-sync — Automatically switch between light/dark themes when the OS changes
• Custom QSS/stylesheet support — Point themes to external .qss or .css files

⚙️ Configuration

• 16 global flags — Control tab visibility, button visibility, drag behavior, floating window chrome, icon styling, and more
• Per-widget feature flags — Granular control over what each dock widget can do: closable, movable, floatable, pinnable
• Insertion order — Sort "Show View" menu items alphabetically or chronologically
• Toggle view actions — Integrate dock widget show/hide into menu bars or toolbars as checkable toggles or one-way show buttons

💾 Persistence

• JSON layout serialization — Save and restore complete window layouts to/from JSON files
• Perspectives — Save named layout presets (e.g., "Coding Mode", "Presentation Mode") and switch between them instantly
• Atomic file I/O — Layouts are written atomically (temp file + rename) to prevent corruption

🎯 Icons & Chrome

• SVG-based icon system — Theme-aware SVG icons with automatic color tinting
• Custom icon provider — Register a directory of SVG icons for use across tabs and menus
• Painted chrome — Custom-drawn title bars, tab buttons, splitter handles, and drop indicators with rounded corners and hover states
• Frameless windows — Custom (PySideSix-Frameless-Window) title bars for the main window and floating containers with a synchronous double-click-to-maximize, DWM shadow, and resize borders
• Chromeless floating windows — Optional bare floating surfaces without any title bar

Quick Start

Installation

pip install pyside6
# Clone Lace
git clone https://github.com/yourusername/lace.git
cd lace

Minimal Example

import sys
from PySide6.QtWidgets import QApplication, QMainWindow, QTextEdit
from lace import DockManager, DockWidget, DockWidgetArea, apply_dock_theme

app = QApplication(sys.argv)
app.setStyle("Fusion")

window = QMainWindow()
window.setWindowTitle("My App")
window.resize(1200, 800)

# Create the dock manager
dock_manager = DockManager(window)
window.setCentralWidget(dock_manager._root)

# Apply a theme
apply_dock_theme("cyberpunk_neon")

# Add a dock widget
editor = DockWidget("Editor", window)
editor.set_widget(QTextEdit())
editor.set_features(DockWidgetFeature.all_features)
dock_manager.add_dock_widget(DockWidgetArea.center, editor)

window.show()
app.exec()

Full Example

Run the demo application to explore all features:

python demo_app.py

The demo includes:

• Multiple dock widgets with different feature flags (closable, movable, floatable, pinnable)
• Sidebar setup with notification badges
• Theme switching menu with 14 built-in themes
• Global flags menu for live configuration toggling
• Insertion order control
• Sidebar focus mode and badge position controls
• Preset configurations (Default, Minimal, Full)

Screenshots

The frameless main window (custom title bar, dock panels, splitters) across 12 built-in themes.

Full-size captures (main window + frameless floating containers) are in the screenshots/ folder.

Architecture Overview

Lace is built around a clean, modular architecture:

DockManager (facade)
├── DockContainerWidget (root + floating windows)
│   ├── DockSplitter (nested, orientation-aware)
│   └── DockAreaWidget (tabbed regions)
│       ├── DockAreaTitleBar
│       │   └── DockAreaTabBar → DockWidgetTab (×N)
│       └── DockWidget → user content (QTextEdit, QWidget, etc.)
├── SidebarManager (auto-hide panels)
│   ├── SideTabBar → VerticalTabButton (×N)
│   └── SideBarContainer (overlay panel)
├── LayoutSerializer (JSON persistence)
├── DockStyleManager (theme engine)
├── DockThemeBridge (QPalette → Qt children)
└── ThemeManager (OS-aware auto light/dark)

See the Architecture Documentation for a complete module-by-module reference with class hierarchies, signals, and method tables.

Documentation

Project Structure

lace/
├── lace/                          # Main package
│   ├── dock_manager.py            # Central orchestrator (facade)
│   ├── dock_widget.py             # User-facing dock widget wrapper
│   ├── dock_widget_tab.py         # Painted-chrome tab button
│   ├── dock_container_widget.py   # Root + floating container
│   ├── dock_area_widget.py        # Single tabbed region
│   ├── dock_splitter.py           # Nested splitters + resize handles
│   ├── floating_dock_container.py # Top-level floating window
│   ├── floating_dock_container_frameless.py  # Frameless floating window
│   ├── frameless_window.py       # Frameless main/window + LaceStandardTitleBar
│   ├── frameless_titlebar.py     # Dock-theme styling for the custom title bar
│   ├── dock_overlay.py            # Drop-target visual overlays
│   ├── dock_chrome.py             # Drag detector, chrome buttons, frames
│   ├── dock_paint.py              # Painting primitives
│   ├── dock_theme.py              # Theme schemas, ThemeSpec, color math
│   ├── dock_custom_theme.py       # 14 built-in theme presets
│   ├── dock_style_manager.py      # Singleton style manager (subscriber model)
│   ├── dock_theme_bridge.py       # QPalette push to Qt children
│   ├── theme_manager.py           # OS-aware auto dark/light switching
│   ├── layout_serializer.py       # JSON save/restore, perspectives
│   ├── dock_container_state.py    # Low-level tree state save/restore
│   ├── dock_signals.py            # Internal event bus
│   ├── dock_menu.py               # Unified context menu system
│   ├── dock_styled.py             # DockStyled mixin (auto-style registration)
│   ├── dock_icon_provider.py      # SVG icon provider with tinting
│   ├── sidebar_manager.py         # Auto-hide sidebar controller
│   ├── sidebar_tab.py             # Vertical tab button
│   ├── sidebar_tab_bar.py         # Vertical tab strip
│   ├── sidebar_container.py       # Animated overlay panel
│   ├── sidebar_title_bar.py       # Title bar inside overlay panel
│   ├── sidebar_state.py           # Sidebar state compatibility shim
│   ├── eliding_label.py           # QLabel with text elision
│   ├── enums.py                   # All enumerations and flags
│   ├── util.py                    # Utility functions
│   └── _trace.py                  # Optional debug tracing
├── demo_app.py                    # Full-featured demo application
├── dev_smoke/                     # Smoke tests for individual features
├── docs/                          # Documentation
├── lace/resources/lace_icons/     # SVG icons (close, dock, float, pin, etc.)
├── LICENSE                        # Apache-2.0
└── README.md                      # This file

Contributing

Contributions are welcome! Please:

1. Open an issue to discuss significant changes before starting work
2. Follow the existing code style and naming conventions
3. Add smoke tests in dev_smoke/ for new features
4. Update documentation (docs/) for user-facing changes

License

Lace is licensed under the Apache License 2.0. See LICENSE for details.

This project incorporates components from qtpydocking under the BSD 3-Clause License. See LICENSE for full attribution.

Author: opticsWolf
Contact: opticswolf@protonmail.com