Update FlyoutPresenter/MenuFlyoutPresenter

src/Avalonia.Controls/Flyouts/FlyoutPresenter.cs

@@ -1,6 +1,33 @@
-namespace Avalonia.Controls
+using Avalonia.Controls.Primitives;
+using Avalonia.Input;
+using Avalonia.LogicalTree;
+
+namespace Avalonia.Controls
 {
     public class FlyoutPresenter : ContentControl
     {
+        public static readonly StyledProperty<CornerRadius> CornerRadiusProperty =
+            AvaloniaProperty.Register<FlyoutPresenter, CornerRadius>(nameof(CornerRadius));
+
+        public CornerRadius CornerRadius
+        {
+            get => GetValue(CornerRadiusProperty);
+            set => SetValue(CornerRadiusProperty, value);
+        }
+
+        protected override void OnKeyDown(KeyEventArgs e)
+        {
+            if (e.Key == Key.Escape)
+            {
+                var host = this.FindLogicalAncestorOfType<Popup>();
+                if (host != null)
+                {
+                    host.IsOpen = false;
+                    e.Handled = true;
+                }
+            }
+
+            base.OnKeyDown(e);            
+        }
     }
 }

src/Avalonia.Controls/Flyouts/MenuFlyoutPresenter.cs

@@ -1,4 +1,5 @@
-using Avalonia.Controls.Generators;
+using System;
+using Avalonia.Controls.Generators;
 using Avalonia.Controls.Platform;
 using Avalonia.Controls.Primitives;
 using Avalonia.LogicalTree;
@@ -7,6 +8,15 @@ namespace Avalonia.Controls
 {
     public class MenuFlyoutPresenter : MenuBase
     {
+        public static readonly StyledProperty<CornerRadius> CornerRadiusProperty =
+            AvaloniaProperty.Register<MenuFlyoutPresenter, CornerRadius>(nameof(CornerRadius));
+
+        public CornerRadius CornerRadius
+        {
+            get => GetValue(CornerRadiusProperty);
+            set => SetValue(CornerRadiusProperty, value);
+        }
+
         public MenuFlyoutPresenter()
             :base(new DefaultMenuInteractionHandler(true))
         {
@@ -25,7 +35,7 @@ namespace Avalonia.Controls
 
         public override void Open()
         {
-            //Ignore
+            throw new NotSupportedException("Use MenuFlyout.ShowAt(Control) instead");
         }
 
         protected override IItemContainerGenerator CreateItemContainerGenerator()