counterapp.cs

public class CounterView : View
	{
		readonly State<int> count = 0;
		readonly State<int> step = 1;
		readonly State<bool> timerOn = false;
		void init()
		{
			count.Value = 1;
			step.Value = 0;
			timerOn.Value = false;
		}
		[Body]
		View body ()=> new VStack
			{
				new Text($"{count}"),
				new Button("Increment",()=> count.Value += step),
				new Button("Decrement",()=>count.Value -= step),
				new HStack
				{
					new Text("Timer"),
					new Toggle(timerOn,(value)=> {
						timerOn.Value = value;
						tickTimer();
					})
				},
				new Slider(step.Value,through:10,onEditingChanged: (value) => step.Value = (int)value),
				new Text(()=> $"Step Size: {step}"),
				new Button("Reset", ()=>  init())
			};

		async void tickTimer()
		{
			if (!timerOn)
				return;
			await Task.Delay(200);
			count.Value += step;
			tickTimer();
		}
	}