IU

UI framework based on the Fusion/libui.cr library, with custom elements from watzon/cru.

Motivation

Currently avaliable Crystal UI frameworks are either not maintained anymore or the documentation is scarce and a single error might cause a developer to lose motivation, which is why I decided to build IU on top of the LibUI framework which is a multi-platform powerful UI toolkit.

Build status

Features

Widgets

Horizontal box, Vertical box, Checkbox, Combobox, Editable combobox.
Button, Font button, Color button, Radio button.
Datetime picker, Progress bar, Slider, Spinbox.
Text entry, Multiline text entry.
Form, Grid, Group, Table, Tab, Separator.
Image, Label.
Window, Menubar, Area.
Many more.

Platforms

Mac OSX
Linux
Windows (Once crystal will be available on Windows)

Code example

require "iu"

module Example
  include Iu::Components

  # Ability to reuse components extracted to other classes.
  class MyComponent < Iu::ReusableComponent
    def initialize(@id : Int32); end

    def render : Iu::Component
      Group
        .new(title: "MyComponent", margined: true)
        .adopt(
          VerticalBox
            .new(padded: true)
            .adopt(
              Label.new(text: "Hello, World ##{@id}!"),
              stretchy: true
            )
            .adopt(
              Button.new(text: "Click Me!"),
              stretchy: true
            )
        )
    end
  end

  # :nodoc:
  class Application < Iu::Application
    def initialize_component
      window =
        Window.new(
          title: "Example",
          width: 800,
          height: 600,
          menu_bar: false
        )
      
      window.margined = true

      window
        .adopt(
          HorizontalBox
            .new(padded: true)
            .adopt(
              MyComponent.new(1),
              stretchy: true
            )
            .adopt(
              MyComponent.new(2),
              stretchy: true
            )
            .adopt(
              MyComponent.new(3),
              stretchy: true
            )
        )

      window.closing.on do
        exit(0)
      end
      
      window.show
    end
  end
end

app = Example::Application.new

app.should_quit.on do
  exit(0)
end

app.start

Installation

Follow the instructions for installation laid out in andlabs/libui.
Copy the compiled files from step 1 (i.e. files in build/out) to /usr/lib for OSX and Linux users.
Go to your shard.yml file, and enter this in:

dependencies:
  iu:
    github: grkek/iu

Run shards install.