Create HideFlyoutOnClickBehavior.cs

src/Avalonia.Xaml.Interactions.Custom/HideFlyoutOnClickBehavior.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Reactive.Linq;
+using Avalonia.Controls;
+using Avalonia.Controls.Primitives;
+using Avalonia.Interactivity;
+using Avalonia.VisualTree;
+using Avalonia.Xaml.Interactivity;
+
+namespace Avalonia.Xaml.Interactions.Custom;
+
+/// <summary>
+/// 
+/// </summary>
+public class HideFlyoutOnClickBehavior : Behavior<RadioButton>
+{
+	private IDisposable? _subscription;
+
+    /// <summary>
+    /// 
+    /// </summary>
+	protected override void OnAttachedToVisualTree()
+	{
+		base.OnAttachedToVisualTree();
+
+		if (AssociatedObject == null)
+		{
+			return;
+		}
+
+		var fp = AssociatedObject.FindAncestorOfType<FlyoutPresenter>();
+
+		if (fp?.Parent is not Popup popup)
+		{
+			return;
+		}
+
+		_subscription = Observable
+			.FromEventPattern<RoutedEventArgs>(handler => AssociatedObject.Click += handler, handler => AssociatedObject.Click -= handler)
+			.Do(_ =>
+			{
+				// Execute Command if any before closing. Otherwise, it won't execute because Close will destroy the associated object before Click can execute it.
+				if (AssociatedObject.Command != null && AssociatedObject.IsEnabled)
+				{
+					AssociatedObject.Command.Execute(AssociatedObject.CommandParameter);
+				}
+				popup.Close();
+			})
+			.Subscribe();
+	}
+
+    /// <summary>
+    /// 
+    /// </summary>
+	protected override void OnDetachedFromVisualTree()
+	{
+		base.OnDetachedFromVisualTree();
+		_subscription?.Dispose();
+	}
+}