README

LazDarkComp (MetaDarkStyle with Decoupled Form Designer)

LazDarkComp brings a modern dark theme to the Lazarus IDE on Windows 10/11, while keeping the Form Designer (visual design surface) decoupled in classic light mode ($F0F0F0 / clBtnFace).

This solves the classic problem where applying a dark theme turned the designed forms dark and made designing standard Windows applications difficult.

Features

• One-Click Theme Toggle Button: Quick-access button directly on the IDE toolbar and menu (Tools -> Toggle Dark/Light Theme) to easily switch between Light and Dark mode with an instant restart prompt.
• Full Dark IDE: Source Editor, Object Inspector, Messages, Menus, Toolbars, and Docked Panels render in sleek dark mode.
• Decoupled Form Designer: Form design surfaces (Form1) and controls in design mode maintain their clean, native light background ($F0F0F0), grid dots, and standard contrast.
• 100% Self-Contained Package: Requires no modifications to Lazarus or LCL source code.
• Auto-Deployed Editor Scheme: Automatically deploys the curated DarkModern.xml syntax color scheme into Lazarus userschemes.
• Compatible with AnchorDocking / DockedFormEditor: Transparently prevents the dark tabsheet background from bleeding into your design form.
• No recursion / Stack Overflow: Stable Win32 LCL message handling.

Packages

• metadarkstyle.lpk: Base runtime package with Windows 10/11 dark mode logic.
• metadarkstyledsgn.lpk: Design-time package for modern Lazarus (3.0, 3.2, 3.4, 4.0, 4.8, trunk).
• metadarkstyledsgn226.lpk: Design-time package for Lazarus 2.2.6.

System Requirements & Compatibility

• Windows 10 (version 1809+) or Windows 11
• Lazarus 2.2.6, 3.0, 3.2, 3.4, 4.0, 4.8, or trunk
• FPC 3.2.2 or later

Installation

Method 1: Using Lazarus IDE (GUI)

1. Clone or download this repository (e.g. to C:\componentes\darkcomp\lazdarkcomp).
2. Open Lazarus IDE.
3. Open Package -> Open Package File (.lpk)...:
   • Select metadarkstyle.lpk and click Compile.
4. Open Package -> Open Package File (.lpk)...:
   • Select metadarkstyledsgn.lpk (or metadarkstyledsgn226.lpk if using Lazarus 2.2.6).
   • Click Compile.
   • Click Use -> Install.
5. When Lazarus asks to rebuild the IDE, confirm with Yes. Lazarus will rebuild itself and restart automatically.

Method 2: Using Command Line (lazbuild)

If you prefer building from the terminal:

cd C:\componentes\darkcomp\lazdarkcomp

lazbuild --add-package-link metadarkstyle.lpk
lazbuild --add-package-link metadarkstyledsgn.lpk
lazbuild --add-package metadarkstyledsgn
lazbuild --build-ide

Theme Toggle Button (Quick Switch)

LazDarkComp includes a Theme (Tema) toggle button directly in the IDE:

• Toolbar Button: Located on the main Lazarus toolbar for one-click switching.
• Menu Entry: Available under Tools (Ferramentas) -> Toggle Dark/Light Theme (Alternar Tema Claro/Escuro).
• Shortcut: Configurable via Tools -> Options -> Environment -> Key mapping (search for ToggleDarkStyleTheme).
• Clicking the button prompts to restart the IDE, applying the changes cleanly in ~1 second.

Configuring the Themes

1. IDE Dark Theme (MetaDarkStyle)

1. In Lazarus, go to Tools (Ferramentas) -> Options... (Opções da IDE...).
2. Under Environment (Ambiente) -> Dark Style:
   • Set Application Mode to Force Dark (or Allow Dark).
   • Select your preferred scheme (e.g., Modern Dark).
   • Click OK.

2. Editor Syntax Colors (DarkModern Scheme)

The package automatically deploys the DarkModern.xml color scheme into your Lazarus configuration:

1. In Lazarus, go to Tools (Ferramentas) -> Options... (Opções da IDE...).
2. Navigate to Editor -> Display (Exibir) -> Colors (Cores).
3. In the color scheme drop-down list (where Default, Delphi, etc. appear), select DarkModern.
4. Click OK / Apply.

(Note: If you have just installed the package, restart Lazarus once so it registers newly deployed schemes).

Repository Structure

• src/: Core units for dark theme implementation and form designer decoupling hooks.
• src/dsgn/: IDE integration, options frame, and auto-deploy logic.
• userschemes/: Pre-configured editor color schemes (DarkModern.xml).
• docs/: Additional documentation and notes.

License

GNU Lesser General Public License (LGPL 2.1) with linking exception, matching Lazarus and Free Pascal license terms.