MainPage.xaml.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Threading.Tasks;
using Windows.UI.Core;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Waher.Events;

// The Blank Page item template is documented at https://go.microsoft.com/fwlink/?LinkId=402352&clcid=0x409

namespace ControllerXmpp
{
	/// <summary>
	/// An empty page that can be used on its own or navigated to within a Frame.
	/// </summary>
	public sealed partial class MainPage : Page
	{
		private static MainPage instance = null;
		private Events events;

		public MainPage()
		{
			this.InitializeComponent();

			this.events = new MainPage.Events();
			Log.Register(this.events);

			if (instance is null)
				instance = this;
		}

		private void Page_Unloaded(object sender, RoutedEventArgs e)
		{
			Log.Unregister(this.events);
			this.events = null;

			if (instance == this)
				instance = null;
		}

		public static MainPage Instance
		{
			get { return instance; }
		}

		public async void LightUpdated(double Value, int NrDec, string Unit)
		{
			await this.Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => this.Light.Text = Value.ToString("F" + NrDec.ToString()) + " " + Unit);
		}

		public async void MotionUpdated(bool Motion)
		{
			await this.Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => this.Motion.Text = Motion ? "DETECTED" : "-");
		}

		public async void RelayUpdated(bool Output)
		{
			await this.Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => this.Relay.Text = Output ? "ON" : "OFF");
		}

		public async void AddLogMessage(string Message)
		{
			DateTime TP = DateTime.Now;

			await this.Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
			{
				this.EventsPanel.Children.Insert(0, new TextBlock() { Text = Message, TextWrapping = TextWrapping.Wrap });

				while (this.EventsPanel.Children.Count > 1000)
					this.EventsPanel.Children.RemoveAt(1000);
			});
		}

		private class Events : EventSink
		{
			public Events() : base(string.Empty)
			{
			}

			public override Task Queue(Event Event)
			{
				StringBuilder sb = new StringBuilder(Event.Message);

				if (!string.IsNullOrEmpty(Event.Object))
				{
					sb.Append(' ');
					sb.Append(Event.Object);
				}

				if (!string.IsNullOrEmpty(Event.Actor))
				{
					sb.Append(' ');
					sb.Append(Event.Actor);
				}

				foreach (KeyValuePair<string, object> Parameter in Event.Tags)
				{
					sb.Append(" [");
					sb.Append(Parameter.Key);
					sb.Append("=");
					if (Parameter.Value != null)
						sb.Append(Parameter.Value.ToString());
					sb.Append("]");
				}

				if (Event.Type >= EventType.Critical && !string.IsNullOrEmpty(Event.StackTrace))
				{
					sb.Append("\r\n\r\n");
					sb.Append(Event.StackTrace);
				}

				MainPage.Instance.AddLogMessage(sb.ToString());

				return Task.CompletedTask;
			}
		}

	}
}