Improve LinkLabel control

Source/LibationAvalonia/App.axaml

@@ -1,6 +1,7 @@
 <Application xmlns="https://github.com/avaloniaui"
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:local="using:LibationAvalonia"
+             xmlns:controls="using:LibationAvalonia.Controls"
 			 x:Class="LibationAvalonia.App"
              Name="Libation">
 
@@ -69,6 +70,10 @@
 				<Setter Property="Background" Value="{DynamicResource SystemControlBackgroundBaseLowBrush}" />
 			</Style>
 		</Style>
+		<Style Selector="controls|LinkLabel">
+			<Setter Property="Foreground" Value="{DynamicResource HyperlinkNew}"/>
+			<Setter Property="ForegroundVisited" Value="{DynamicResource HyperlinkVisited}"/>
+		</Style>
 	</Application.Styles>
 
 	<NativeMenu.Menu>

Source/LibationAvalonia/App.axaml.cs

@@ -27,7 +27,6 @@ namespace LibationAvalonia
 		public static IBrush ProcessQueueBookCancelledBrush { get; private set; }
 		public static IBrush ProcessQueueBookDefaultBrush { get; private set; }
 		public static IBrush SeriesEntryGridBackgroundBrush { get; private set; }
-		public static IBrush HyperlinkVisited { get; private set; }
 
 		public static IAssetLoader AssetLoader { get; private set; }
 
@@ -230,7 +229,6 @@ namespace LibationAvalonia
 			ProcessQueueBookCancelledBrush = AvaloniaUtils.GetBrushFromResources(nameof(ProcessQueueBookCancelledBrush));
 			SeriesEntryGridBackgroundBrush = AvaloniaUtils.GetBrushFromResources(nameof(SeriesEntryGridBackgroundBrush));
 			ProcessQueueBookDefaultBrush = AvaloniaUtils.GetBrushFromResources(nameof(ProcessQueueBookDefaultBrush));
-			HyperlinkVisited = AvaloniaUtils.GetBrushFromResources(nameof(HyperlinkVisited));
 		}
 	}
 }

Source/LibationAvalonia/Controls/LinkLabel.axaml

@@ -3,10 +3,10 @@
              xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+             xmlns:controls="using:LibationAvalonia.Controls"
              x:Class="LibationAvalonia.Controls.LinkLabel">
 	<TextBlock.Styles>
-		<Style Selector="TextBlock">
+		<Style Selector="controls|LinkLabel">
-			<Setter Property="Foreground" Value="{DynamicResource HyperlinkNew}"/>
 			<Setter Property="TextDecorations" Value="Underline"/>
 		</Style>
 	</TextBlock.Styles>

Source/LibationAvalonia/Controls/LinkLabel.axaml.cs

@@ -1,14 +1,57 @@
+using Avalonia;
 using Avalonia.Controls;
+using Avalonia.Data;
 using Avalonia.Input;
+using Avalonia.Interactivity;
+using Avalonia.Media;
 using Avalonia.Styling;
 using System;
+using System.Windows.Input;
 
 namespace LibationAvalonia.Controls
 {
-	public partial class LinkLabel : TextBlock, IStyleable
+	public partial class LinkLabel : TextBlock, IStyleable, ICommandSource
 	{
-		Type IStyleable.StyleKey => typeof(TextBlock);
+		Type IStyleable.StyleKey => typeof(LinkLabel);
+
+		public static readonly StyledProperty<ICommand> CommandProperty =
+			AvaloniaProperty.Register<LinkLabel, ICommand>(nameof(Command), enableDataValidation: true);
+
+		public static readonly StyledProperty<object> CommandParameterProperty =
+		   AvaloniaProperty.Register<LinkLabel, object>(nameof(CommandParameter));
+
+		public static readonly StyledProperty<IBrush> ForegroundVisitedProperty =
+		   AvaloniaProperty.Register<LinkLabel, IBrush>(nameof(ForegroundVisited));
+
+		public static readonly RoutedEvent<RoutedEventArgs> ClickEvent =
+			RoutedEvent.Register<Button, RoutedEventArgs>(nameof(Click), RoutingStrategies.Bubble);
+
+		public ICommand Command
+		{
+			get => GetValue(CommandProperty);
+			set => SetValue(CommandProperty, value);
+		}
+
+		public object CommandParameter
+		{
+			get => GetValue(CommandParameterProperty);
+			set => SetValue(CommandParameterProperty, value);
+		}
+
+		public IBrush ForegroundVisited
+		{
+			get => GetValue(ForegroundVisitedProperty);
+			set => SetValue(ForegroundVisitedProperty, value);
+		}
+
+		public event EventHandler<RoutedEventArgs> Click
+		{
+			add => AddHandler(ClickEvent, value);
+			remove => RemoveHandler(ClickEvent, value);
+		}
+
 		private static readonly Cursor HandCursor = new Cursor(StandardCursorType.Hand);
+		private bool _commandCanExecute = true;
 		public LinkLabel()
 		{
 			InitializeComponent();
@@ -17,7 +60,19 @@ namespace LibationAvalonia.Controls
 
 		private void LinkLabel_Tapped(object sender, TappedEventArgs e)
 		{
-			Foreground = App.HyperlinkVisited;
+			Foreground = ForegroundVisited;
+			if (IsEffectivelyEnabled)
+			{
+
+				var args = new RoutedEventArgs(ClickEvent);
+				RaiseEvent(args);
+
+				if (!args.Handled && Command?.CanExecute(CommandParameter) == true)
+				{
+					Command.Execute(CommandParameter);
+					args.Handled = true;
+				}
+			}
 		}
 
 		protected override void OnPointerEntered(PointerEventArgs e)
@@ -30,5 +85,33 @@ namespace LibationAvalonia.Controls
 			this.Cursor = Cursor.Default;
 			base.OnPointerExited(e);
 		}
+		protected override bool IsEnabledCore => base.IsEnabledCore && _commandCanExecute;
+
+		protected override void UpdateDataValidation(AvaloniaProperty property, BindingValueType state, Exception error)
+		{
+			base.UpdateDataValidation(property, state, error);
+			if (property == CommandProperty)
+			{
+				if (state == BindingValueType.BindingError)
+				{
+					if (_commandCanExecute)
+					{
+						_commandCanExecute = false;
+						UpdateIsEffectivelyEnabled();
+					}
+				}
+			}
+		}
+
+		public void CanExecuteChanged(object sender, EventArgs e)
+		{
+			var canExecute = Command == null || Command.CanExecute(CommandParameter);
+
+			if (canExecute != _commandCanExecute)
+			{
+				_commandCanExecute = canExecute;
+				UpdateIsEffectivelyEnabled();
+			}
+		}
 	}
 }

Source/LibationAvalonia/Dialogs/AboutDialog.axaml

@@ -54,7 +54,7 @@
 
 				<WrapPanel>
 					<WrapPanel.Styles>
-						<Style Selector="TextBlock">
+						<Style Selector="controls|LinkLabel">
 							<Setter Property="Margin" Value="5,0" />
 							<Setter Property="FontSize" Value="13" />
 						</Style>