Fixes #2225. MenuBar leaves trails when mounted in a Window.

Terminal.Gui/Core/Window.cs

@@ -280,15 +280,16 @@ namespace Terminal.Gui {
 			//var borderLength = Border.DrawMarginFrame ? 1 : 0;
 
 			// FIXED: Why do we draw the frame twice? This call is here to clear the content area, I think. Why not just clear that area?
-			if (!NeedDisplay.IsEmpty) {
+			if (!NeedDisplay.IsEmpty || ChildNeedsDisplay || LayoutNeeded) {
 				Driver.SetAttribute (GetNormalColor ());
 				Clear ();
+				contentView.SetNeedsDisplay ();
 			}
 			var savedClip = contentView.ClipToBounds ();
 
 			// Redraw our contentView
 			// DONE: smartly constrict contentView.Bounds to just be what intersects with the 'bounds' we were passed
-			contentView.Redraw (!NeedDisplay.IsEmpty ? contentView.Bounds : bounds);
+			contentView.Redraw (!NeedDisplay.IsEmpty || ChildNeedsDisplay || LayoutNeeded ? contentView.Bounds : bounds);
 			Driver.Clip = savedClip;
 
 			ClearLayoutNeeded ();

Terminal.Gui/Views/Menu.cs

@@ -690,6 +690,7 @@ namespace Terminal.Gui {
 				}
 			} while (barItems.Children [current] == null || disabled);
 			SetNeedsDisplay ();
+			SetParentSetNeedsDisplay ();
 			if (!host.UseSubMenusSingleFrame)
 				host.OnMenuOpened ();
 			return true;
@@ -737,11 +738,24 @@ namespace Terminal.Gui {
 				}
 			} while (barItems.Children [current] == null || disabled);
 			SetNeedsDisplay ();
+			SetParentSetNeedsDisplay ();
 			if (!host.UseSubMenusSingleFrame)
 				host.OnMenuOpened ();
 			return true;
 		}
 
+		private void SetParentSetNeedsDisplay ()
+		{
+			if (host.openSubMenu != null) {
+				foreach (var menu in host.openSubMenu) {
+					menu.SetNeedsDisplay ();
+				}
+			}
+
+			host?.openMenu.SetNeedsDisplay ();
+			host.SetNeedsDisplay ();
+		}
+
 		public override bool MouseEvent (MouseEvent me)
 		{
 			if (!host.handled && !host.HandleGrabView (me, this)) {
@@ -778,6 +792,7 @@ namespace Terminal.Gui {
 					current = me.Y - 1;
 				if (host.UseSubMenusSingleFrame || !CheckSubMenu ()) {
 					SetNeedsDisplay ();
+					SetParentSetNeedsDisplay ();
 					return true;
 				}
 				host.OnMenuOpened ();
@@ -806,6 +821,7 @@ namespace Terminal.Gui {
 				return host.CloseMenu (false, true);
 			} else {
 				SetNeedsDisplay ();
+				SetParentSetNeedsDisplay ();
 			}
 			return true;
 		}
@@ -1587,7 +1603,7 @@ namespace Terminal.Gui {
 					var subMenu = openCurrentMenu.current > -1 && openCurrentMenu.barItems.Children.Length > 0
 						? openCurrentMenu.barItems.SubMenu (openCurrentMenu.barItems.Children [openCurrentMenu.current])
 						: null;
-					if ((selectedSub == -1 || openSubMenu == null || openSubMenu?.Count == selectedSub) && subMenu == null) {
+					if ((selectedSub == -1 || openSubMenu == null || openSubMenu?.Count - 1 == selectedSub) && subMenu == null) {
 						if (openSubMenu != null && !CloseMenu (false, true))
 							return;
 						NextMenu (false, ignoreUseSubMenusSingleFrame);

UnitTests/MenuTests.cs

@@ -1498,7 +1498,7 @@ Edit
 			Assert.True (menu.IsMenuOpen);
 			Assert.False (tf.HasFocus);
 			Application.Top.Redraw (Application.Top.Bounds);
-			TestHelpers.AssertDriverContentsAre (expectedMenu.expectedSubMenuOpen(0), output);
+			TestHelpers.AssertDriverContentsAre (expectedMenu.expectedSubMenuOpen (0), output);
 
 			// Right - Edit has no sub menu; this tests that no sub menu shows
 			Assert.True (menu.openMenu.ProcessKey (new KeyEvent (Key.CursorRight, new KeyModifiers ())));
@@ -1636,5 +1636,85 @@ Edit
 00000000000000
 00000000000000", attributes);
 		}
+
+		[Fact, AutoInitShutdown]
+		public void MenuBar_In_Window_Without_Other_Views ()
+		{
+			var win = new Window ();
+			var menu = new MenuBar (new MenuBarItem [] {
+				new MenuBarItem ("File", new MenuItem [] {
+					new MenuItem ("New", "", null)
+				}),
+				new MenuBarItem ("Edit", new MenuItem [] {
+					new MenuBarItem ("Delete", new MenuItem [] {
+						new MenuItem ("All", "", null),
+						new MenuItem ("Selected", "", null)
+					})
+				})
+			}); ;
+			win.Add (menu);
+			var top = Application.Top;
+			top.Add (win);
+			Application.Begin (top);
+			((FakeDriver)Application.Driver).SetBufferSize (40, 8);
+
+			TestHelpers.AssertDriverContentsWithFrameAre (@"
+┌──────────────────────────────────────┐
+│ File  Edit                           │
+│                                      │
+│                                      │
+│                                      │
+│                                      │
+│                                      │
+└──────────────────────────────────────┘", output);
+
+			Assert.True (win.ProcessHotKey (new KeyEvent (Key.F9, new KeyModifiers ())));
+			win.Redraw (win.Bounds);
+			TestHelpers.AssertDriverContentsWithFrameAre (@"
+┌──────────────────────────────────────┐
+│ File  Edit                           │
+│┌──────┐                              │
+││ New  │                              │
+│└──────┘                              │
+│                                      │
+│                                      │
+└──────────────────────────────────────┘", output);
+
+			Assert.True (menu.ProcessKey (new KeyEvent (Key.CursorRight, new KeyModifiers ())));
+			win.Redraw (win.Bounds);
+			TestHelpers.AssertDriverContentsWithFrameAre (@"
+┌──────────────────────────────────────┐
+│ File  Edit                           │
+│      ┌─────────┐                     │
+│      │ Delete ►│                     │
+│      └─────────┘                     │
+│                                      │
+│                                      │
+└──────────────────────────────────────┘", output);
+
+			Assert.True (menu.openMenu.ProcessKey (new KeyEvent (Key.CursorRight, new KeyModifiers ())));
+			win.Redraw (win.Bounds);
+			TestHelpers.AssertDriverContentsWithFrameAre (@"
+┌──────────────────────────────────────┐
+│ File  Edit                           │
+│      ┌─────────┐                     │
+│      │ Delete ►│┌───────────┐        │
+│      └─────────┘│ All       │        │
+│                 │ Selected  │        │
+│                 └───────────┘        │
+└──────────────────────────────────────┘", output);
+
+			Assert.True (menu.openMenu.ProcessKey (new KeyEvent (Key.CursorRight, new KeyModifiers ())));
+			win.Redraw (win.Bounds);
+			TestHelpers.AssertDriverContentsWithFrameAre (@"
+┌──────────────────────────────────────┐
+│ File  Edit                           │
+│┌──────┐                              │
+││ New  │                              │
+│└──────┘                              │
+│                                      │
+│                                      │
+└──────────────────────────────────────┘", output);
+		}
 	}
 }