UIng is a Crystal binding for kojix2/libui-ng. You can use the Crystal language to create cross-platform native desktop apps.
Documentation: Guide · English · 日本語 · API Reference
libui-ng uses the native APIs of each platform: Win32 API, Direct2D, and DirectWrite on Windows; Cocoa (AppKit) on macOS; and GTK+ 3.10+ and Pango on Linux/Unix. You get windows, buttons, text boxes, menus, dialogs, drawing areas, and other standard widgets.
| Windows | Mac | Linux |
|---|---|---|
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📸 Live Documentation: All screenshots in the README are automatically generated by GitHub Actions on every push, ensuring cross-platform compatibility (Linux, Windows, macOS).
- macOS: x86_64 (64-bit), ARM64 (Apple Silicon)
- Linux: x86_64 (64-bit), ARM64
- Windows: x86_64 (64-bit, MSVC, MinGW, and UCRT)
Add the dependency to your shard.yml:
dependencies:
uing:
github: kojix2/uingRun shards install. The post-install script downloads the required libui-ng binary for the current platform. See the installation guide for platform-specific setup.
Create hello.cr:
require "uing"
UIng.init
window = UIng::Window.new("Hello World", 300, 200)
window.on_closing do
UIng.quit
true
end
button = UIng::Button.new("Click me")
button.on_clicked do
window.msg_box("Info", "Button clicked!")
end
window.child = button
window.show
UIng.main
UIng.uninitRun it with:
crystal run hello.crTo run the full control gallery from a checkout:
git clone https://github.com/kojix2/uing
cd uing
shards install
crystal run examples/gallery/control_gallery.crContinue with the First Steps guide. The optional block-based DSL is covered in Coding Styles.
This gallery shows screenshots of example on three platforms (Ubuntu, Windows, macOS).
Images are automatically generated and stored in the screenshots branch.
| Control | Ubuntu | Windows | macOS |
|---|---|---|---|
| Window |  |
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| Toolbar |  |
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Note: Toolbar is a feature specific to kojix2/libui-ng. It is experimental and may change.
| Control | Ubuntu | Windows | macOS |
|---|---|---|---|
| Button |  |
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| Checkbox |  |
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| ColorButton |  |
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| Combobox |  |
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| DateTimePicker |  |
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| EditableCombobox |  |
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| Entry |  |
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| FontButton |  |
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| Label |  |
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| MultilineEntry |  |
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| Progressbar |  |
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| RadioButtons |  |
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| Separator |  |
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| Slider |  |
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| Spinbox |  |
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| Container | Ubuntu | Windows | macOS |
|---|---|---|---|
| Box (Horizontal) |  |
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| Box (Vertical) |  |
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| Tab |  |
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| Form |  |
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| Group |  |
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| Grid |  |
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| Grid (Calculator) |  |
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| Example | Ubuntu | Windows | macOS |
|---|---|---|---|
| basic_table |  |
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| csv_viewer |  |
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| advanced_table |  |
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| Example | Ubuntu | Windows | macOS |
|---|---|---|---|
| basic_area |  |
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| area_basic_shapes |  |
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| area_colors_and_brushes |  |
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| area_analog_clock |  |
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| area_matrix |  |
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| basic_draw_text |  |
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| reversi |  |
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| area_breakout |  |
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| boid3d |  |
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| Example | Ubuntu | Windows | macOS |
|---|---|---|---|
| basic_menu |  |
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| Example | Ubuntu | Windows | macOS |
|---|---|---|---|
| basic_msg_box |  |
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| basic_msg_box_error |  |
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| Example | Ubuntu | Windows | macOS |
|---|---|---|---|
| area_draw_image |  |
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| basic_image_view |  |
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Note: Image display is a feature introduced in kojix2/libui-ng. This feature is not present in the original libui-ng.
See the development and contribution guide. Bug reports, pull requests, and articles about UIng are welcome.
MIT License