Some more GUI stuff, in C#

test.cs

using System;

using AirKit;
using AirKit.Layout;
using AirKit.Material;

namespace AirKit.Demo
{
  class MainView : View
  {
    int value;

    public override Element* Build()
    {
      return new MatScaffold(
        appbar: new MatAppBar(
          title: "AirKit Demo",
          new LayCenter(
            horizontal: true,
            vertical: true,
            new LayBox(
              orientation: LayOrientation.VERTICAL,
              new MatText(
                text: $"I am ${value}"
              ),
              new MatButtonBox(
                new MatButton(
                  raised: true,
                  text: "Increment",
                  onClicked: () => {
                    update(() => {
                      value += 1;
                    });
                  }
                ),
                new MatButton(
                  raised: true,
                  text: "Decrement",
                  onClicked: () => {
                    update(() => {
                      value -= 1;
                    });
                  }
                )
              )
            )
          )
        )
      );
    }
  }

  class Program
  {
    [STAThread]
    static void Main(string[] args)
    {

      var app = new Application(
        name: "AirKit Demo",
        mainView: new MainView()
      );

    }
  }
}