Mac: Fix disabled menu items with a Dialog

src/Eto.Mac/AppDelegate.cs

@@ -29,7 +29,10 @@ public override void DidFinishLaunching(NSNotification notification)
 		{
 			var handler = Application.Instance.Handler as ApplicationHandler;
 			if (handler != null)
+			{
+				handler.InitialMenu = Messaging.IntPtr_objc_msgSend(NSApplication.SharedApplication.Handle, MacWindow.selMainMenu);
 				handler.Initialize(this);
+			}
 		}
 
 		public override NSApplicationTerminateReply ApplicationShouldTerminate(NSApplication sender)

src/Eto.Mac/Forms/ApplicationHandler.cs

@@ -15,6 +15,9 @@ public class ApplicationHandler : WidgetHandler<NSApplication, Application, Appl
 
 		public bool AllowClosingMainForm { get; set; }
 
+		// pointer to the initial menu so we know whether we want to keep it or not for the main form
+		internal IntPtr InitialMenu { get; set; }
+
 		/// <summary>
 		/// Gets or sets a value indicating whether native macOS crash reports are generated for uncaught .NET exceptions.
 		/// </summary>
@@ -193,7 +196,7 @@ public void Run()
 
 
 				EtoBundle.Init();
-
+				
 				EtoFontManager.Install();
 
 				if (Control.Delegate == null)

src/Eto.Mac/Forms/MacWindow.cs

@@ -787,6 +787,9 @@ void SetMenu()
 				if (oldMenu == IntPtr.Zero)
 				{
 					oldMenu = Messaging.IntPtr_objc_msgSend(NSApplication.SharedApplication.Handle, MacWindow.selMainMenu);
+					// don't save the initial menu which macOS creates on startup
+					if (oldMenu == ApplicationHandler.Instance.InitialMenu)
+						oldMenu = IntPtr.Zero;
 					if (oldMenu != IntPtr.Zero)
 					{
 						// remember old native menu so we can restore it later

src/Eto.Mac/Forms/Menu/MenuHandler.cs

@@ -109,15 +109,28 @@ public bool WorksWhenModal
 				var worksWhenModal = Widget.Properties.Get<bool?>(MenuHandler.WorksWhenModal_Key);
 				if (worksWhenModal == null)
 				{
-					// find top level menu
+					// traverse menu tree to find any parent that specifies it should work when modal
 					var menu = Control.Menu;
-					while (menu.Supermenu != null)
-						menu = menu.Supermenu;
+					do
+					{
+						if (menu is EtoMenu etoMenu && etoMenu.WorksWhenModal)
+							return true;
 
-					worksWhenModal = (menu as EtoMenu)?.WorksWhenModal ?? false;
-					Widget.Properties.Set(MenuHandler.WorksWhenModal_Key, worksWhenModal);
+						menu = menu.Supermenu;
+					} while (menu.Supermenu != null);
+
+					// check the top menu (e.g. context menu or menu bar)
+					if (menu is EtoMenu topEtoMenu && topEtoMenu.WorksWhenModal)
+						return true;
+
+					// allow all items if it is in current dialog's menu.
+					if (NSApplication.SharedApplication.KeyWindow is EtoWindow window && window.Handler?.Widget is Dialog dialog)
+					{
+						var currentMenu = MenuBarHandler.GetControl(dialog.Menu);
+						return currentMenu == menu;
+					}
 				}
-				return worksWhenModal.Value;
+				return worksWhenModal ?? false;
 			}
 			set => Widget.Properties.Set(MenuHandler.WorksWhenModal_Key, value);
 		}