Wpf: Allow intrinsic key behavior of menu shortcut keys when item is disabled

src/Eto.Wpf/Forms/Menu/MenuItemHandler.cs

@@ -70,11 +70,42 @@ public string ToolTip
 			set { Control.ToolTip = value; }
 		}
 
+
+		class EtoKeyGesture : swi.InputGesture
+		{
+			public EtoKeyGesture(MenuItemHandler<TControl, TWidget, TCallback> menuItemHandler, swi.Key key, swi.ModifierKeys modifiers)
+			{
+				MenuItemHandler = menuItemHandler;
+				Key = key;
+				Modifiers = modifiers;
+			}
+
+			public MenuItemHandler<TControl, TWidget, TCallback> MenuItemHandler { get; }
+
+			public swi.Key Key { get; }
+			public swi.ModifierKeys Modifiers { get; }
+
+			public override bool Matches(object targetElement, swi.InputEventArgs inputEventArgs)
+			{
+				// only match if enabled, which is different from WPF's default behavior
+				// this allows specific keys to be used in the application when the menu item is disabled
+				if (!MenuItemHandler.Enabled)
+					return false;
+				if (inputEventArgs is swi.KeyEventArgs args && IsDefinedKey(args.Key))
+				{
+					return ( (int)Key == (int)args.Key ) && ( Modifiers == swi.Keyboard.Modifiers );
+				}
+				return false;
+			}
+
+			internal static bool IsDefinedKey(swi.Key key) => key >= swi.Key.None && key <= swi.Key.OemClear;			
+		}
+
 		public Keys Shortcut
 		{
 			get
 			{
-				var keyBinding = Control.InputBindings.OfType<swi.KeyBinding>().FirstOrDefault();
+				var keyBinding = Control.InputBindings.OfType<EtoKeyGesture>().FirstOrDefault();
 				return keyBinding == null ? Keys.None : keyBinding.Key.ToEtoWithModifier(keyBinding.Modifiers);
 			}
 			set
@@ -85,22 +116,26 @@ public Keys Shortcut
 				{
 					var key = value.ToWpfKey();
 					var modifier = value.ToWpfModifier();
-                    Control.InputBindings.Add(new swi.KeyBinding { Key = key, Modifiers = modifier, Command = this });
+					var gesture = new EtoKeyGesture(this, key, modifier);
+					Control.InputBindings.Add(new swi.InputBinding(this, gesture));
 					Control.InputGestureText = value.ToShortcutString();
 					AddKeyBindings(Control);
 				}
 				else
 					Control.InputGestureText = null;
 			}
 		}
-
+		
 		public bool Enabled
 		{
-			get { return Control.IsEnabled; }
+			get => Control.IsEnabled;
 			set
 			{
-				Control.IsEnabled = value;
-				OnCanExecuteChanged(EventArgs.Empty);
+				if (Control.IsEnabled != value)
+				{
+					Control.IsEnabled = value;
+					OnCanExecuteChanged(EventArgs.Empty);
+				}
 			}
 		}
 

src/Eto.Wpf/Forms/WpfWindow.cs

@@ -478,16 +478,6 @@ public void Close()
 
 		}
 
-		void CopyKeyBindings(swc.ItemCollection items)
-		{
-			foreach (var item in items.OfType<swc.MenuItem>())
-			{
-				Control.InputBindings.AddRange(item.InputBindings);
-				if (item.HasItems)
-					CopyKeyBindings(item.Items);
-			}
-		}
-
 		public MenuBar Menu
 		{
 			get { return menu; }
@@ -496,6 +486,7 @@ public MenuBar Menu
 				if (IsAttached)
 					throw new NotSupportedException();
 				menu = value;
+				Control.InputBindings.Clear();
 				if (menu != null)
 				{
 					var handler = (MenuBarHandler)menu.Handler;

test/Eto.Test/UnitTests/Forms/MenuItemTests.cs

@@ -105,6 +105,79 @@ public void MenuItemEnabledShouldUpdateCommandIfSpecified()
 			Assert.IsFalse(command.Enabled, "#3.1");
 			Assert.AreEqual(item.Enabled, command.Enabled, "#3.2");
 		}
+
+		[TestCase(true, Keys.E, false, true)] // Fails in Gtk, Wpf (shortcut takes precedence over intrinsic behaviour)
+		[TestCase(false, Keys.E, false, true)]
+		[TestCase(true, Keys.E | Keys.Control, false, false)] // Fails in Gtk, Mac (menu shortcuts always takes precedence)
+		[TestCase(true, Keys.E | Keys.Control, true, false)] // Fails in Gtk, Mac (menu shortcuts always takes precedence)
+		[TestCase(false, Keys.E | Keys.Control, true, false)]
+		[TestCase(false, Keys.E | Keys.Control, false, false)]
+		[ManualTest]
+		public void TextBoxShouldAcceptInputEvenWhenShortcutDefined(bool enabled, Keys key, bool handleKey, bool shouldBeIntrinsic)
+		{
+			ControlShouldAcceptInputEvenWhenShortcutDefined<TextBox>(enabled, key, handleKey, shouldBeIntrinsic);
+		}
+
+		[TestCase(true, Keys.E, false, false)]
+		[TestCase(false, Keys.E, false, false)]
+		[TestCase(true, Keys.E, true, false)]
+		[TestCase(false, Keys.E, true, false)]
+		[TestCase(true, Keys.E | Keys.Control, false, false)] // Fails in Gtk, Mac (menu shortcuts always takes precedence)
+		[TestCase(true, Keys.E | Keys.Control, true, false)] // Fails in Gtk, Mac (menu shortcuts always takes precedence)
+		[TestCase(false, Keys.E | Keys.Control, true, false)]
+		[TestCase(false, Keys.E | Keys.Control, false, false)]
+		[ManualTest]
+		public void DrawableShouldAcceptInputEvenWhenShortcutDefined(bool enabled, Keys key, bool handleKey, bool shouldBeIntrinsic)
+		{
+			ControlShouldAcceptInputEvenWhenShortcutDefined<Drawable>(enabled, key, handleKey, shouldBeIntrinsic, d => d.CanFocus = true);
+		}
 
+		void ControlShouldAcceptInputEvenWhenShortcutDefined<T>(bool enabled, Keys key, bool handleKey, bool shouldBeIntrinsic, Action<T> initialize = null)
+			where T: Control, new()
+		{
+			var itemWasClicked = false;
+			var keyWasPressed = false;
+			ManualForm($"Press the {key.ToShortcutString()} key", form =>
+			{
+				var menu = new MenuBar();
+				var item = new ButtonMenuItem { Text = "Disabled Item", Enabled = enabled, Shortcut = key };
+				item.Click += (sender, e) =>
+				{
+					itemWasClicked = true;
+					Log.Write(sender, "Item was clicked");
+				};
+				menu.Items.Add(new SubMenuItem { Text = "File", Items = { item } });
+				form.Menu = menu;
+				var control = new T { Size = new Size(200, 200) };
+				initialize?.Invoke(control);
+				control.KeyDown += (sender, e) =>
+				{
+					if (e.KeyData == key)
+					{
+						// key was pressed! yay.
+						Log.Write(sender, "Key was pressed on control");
+						keyWasPressed = true;
+
+						if (handleKey)
+							e.Handled = true;
+					}
+				};
+				form.Shown += (sender, e) => control.Focus();
+
+				return control;
+			});
+
+			if (!enabled || handleKey || shouldBeIntrinsic)
+			{
+				Assert.IsFalse(itemWasClicked, "#1 - ButtonMenuItem was triggered, but should not have been");
+			}
+			else
+			{
+				Assert.IsTrue(itemWasClicked, "#1 - ButtonMenuItem was not triggered");
+			}
+
+			Assert.IsTrue(keyWasPressed, "#2 - Key was not pressed");
+		}
+
 	}
 }