Fixed nested tabgroup nav!

Terminal.Gui/Application/Application.Keyboard.cs

@@ -300,7 +300,21 @@ public static partial class Application // Keyboard handling
                         // TODO: This OverlapppedTop tomfoolery goes away in addressing #2491
                         if (ApplicationOverlapped.OverlappedTop is null && Current is { })
                         {
-                            return Current.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabGroup);
+                            if (Current.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabGroup))
+                            {
+                                return true;
+                            };
+
+                            //// Go back down the focus chain and focus the first TabGroup
+                            //View []? views = Current.GetSubviewFocusChain (NavigationDirection.Forward, TabBehavior.TabGroup);
+
+                            //if (views.Length > 0)
+                            //{
+                            //    View []? subViews = views [0].GetSubviewFocusChain (NavigationDirection.Forward, TabBehavior.TabStop);
+                            //    return subViews? [0].SetFocus ();
+                            //}
+
+                            return false;
                         }
 
                         ApplicationOverlapped.OverlappedMoveNext ();
@@ -316,7 +330,21 @@ public static partial class Application // Keyboard handling
                         // TODO: This OverlapppedTop tomfoolery goes away in addressing #2491
                         if (ApplicationOverlapped.OverlappedTop is null && Current is { })
                         {
-                            return Current.AdvanceFocus (NavigationDirection.Backward, TabBehavior.TabGroup);
+                            if (Current.AdvanceFocus (NavigationDirection.Backward, TabBehavior.TabGroup))
+                            {
+                                return true;
+                            };
+
+                            //// Go back down the focus chain and focus the first TabGroup
+                            //View []? views = Current.GetSubviewFocusChain (NavigationDirection.Backward, TabBehavior.TabGroup);
+
+                            //if (views.Length > 0)
+                            //{
+                            //    View []? subViews = views [0].GetSubviewFocusChain (NavigationDirection.Backward, TabBehavior.TabStop);
+                            //    return subViews? [0].SetFocus ();
+                            //}
+
+                            return false;
                         }
 
                         ApplicationOverlapped.OverlappedMovePrevious ();

Terminal.Gui/View/View.Navigation.cs

@@ -37,6 +37,7 @@ public partial class View // Focus and cross-view navigation management (TabStop
             return true;
         }
 
+        // AdvanceFocus did not advance
         View [] index = GetSubviewFocusChain (direction, behavior);
 
         if (index.Length == 0)
@@ -44,6 +45,49 @@ public partial class View // Focus and cross-view navigation management (TabStop
             return false;
         }
 
+        if (behavior == TabBehavior.TabGroup)
+        {
+            if (direction == NavigationDirection.Forward && focused == index [^1] && SuperView is null)
+            {
+                // We're at the top of the focus chain. Go back down the focus chain and focus the first TabGroup
+                View [] views = GetSubviewFocusChain (NavigationDirection.Forward, TabBehavior.TabGroup);
+
+                if (views.Length > 0)
+                {
+                    View [] subViews = views [0].GetSubviewFocusChain (NavigationDirection.Forward, TabBehavior.TabStop);
+
+                    if (subViews.Length > 0)
+                    {
+                        if (subViews [0].SetFocus ())
+                        {
+                            return true;
+                        }
+                    }
+                }
+            }
+
+            if (direction == NavigationDirection.Backward && focused == index [0])
+            {
+                // We're at the bottom of the focus chain
+                View [] views = GetSubviewFocusChain (NavigationDirection.Forward, TabBehavior.TabGroup);
+
+                if (views.Length > 0)
+                {
+                    View [] subViews = views [^1].GetSubviewFocusChain (NavigationDirection.Forward, TabBehavior.TabStop);
+
+                    if (subViews.Length > 0)
+                    {
+                        if (subViews [0].SetFocus ())
+                        {
+                            return true;
+                        }
+                    }
+                }
+            }
+
+        }
+
+
         int focusedIndex = index.IndexOf (Focused); // Will return -1 if Focused can't be found or is null
         var next = 0;
 
@@ -57,21 +101,20 @@ public partial class View // Focus and cross-view navigation management (TabStop
             // We're moving beyond the last subview
 
             // Determine if focus should remain in this focus chain, or move to the superview's focus chain
-            // BUGBUG: The logic below is sketchy and barely works. In fact, it doesn't work propertly for all nested TabGroups.
-            // - If we are TabStop and our SuperView has at least one other TabStop subview, move to the SuperView's chain
+
+            // If we are TabStop and our SuperView has at least one other TabStop subview, move to the SuperView's chain
             if (TabStop == TabBehavior.TabStop && SuperView is { } && SuperView.GetSubviewFocusChain (direction, behavior).Length > 1)
             {
                 return false;
             }
 
-            // - If we are TabGroup and our SuperView has at least one other TabGroup subview, move to the SuperView's chain
-            if (TabStop == TabBehavior.TabGroup && SuperView is { TabStop: TabBehavior.TabGroup })
+            // TabGroup is special-cased. 
+            if (focused?.TabStop == TabBehavior.TabGroup)
             {
-                if (behavior == TabBehavior.TabGroup)
+                if (SuperView?.GetSubviewFocusChain (direction, TabBehavior.TabGroup)?.Length > 0)
                 {
-                    // Wrap to first focusable views
-                    // BUGBUG: This should do a Restore Focus instead
-                    index = GetSubviewFocusChain (direction, null);
+                    // Our superview has a TabGroup subview; signal we couldn't move so we nav out to it
+                    return false;
                 }
             }
         }
@@ -560,7 +603,7 @@ public partial class View // Focus and cross-view navigation management (TabStop
 
             if (appFocused is { } || appFocused == this)
             {
-               Application.Navigation.SetFocused (newFocusedView ?? SuperView);
+                Application.Navigation.SetFocused (newFocusedView ?? SuperView);
             }
         }
 
@@ -635,7 +678,7 @@ public partial class View // Focus and cross-view navigation management (TabStop
     /// <param name="behavior"></param>
     /// <returns></returns>
     /// GetScopedTabIndexes
-    private View [] GetSubviewFocusChain (NavigationDirection direction, TabBehavior? behavior)
+    internal View [] GetSubviewFocusChain (NavigationDirection direction, TabBehavior? behavior)
     {
         IEnumerable<View>? fitleredSubviews;
 

Terminal.Gui/Views/DatePicker.cs

@@ -189,7 +189,6 @@ public class DatePicker : View
         Date = date;
         _dateLabel = new Label { X = 0, Y = 0, Text = "Date: " };
         CanFocus = true;
-        TabStop = TabBehavior.TabGroup;
 
         _calendar = new TableView
         {

UICatalog/Scenarios/Navigation.cs

@@ -64,15 +64,19 @@ public class Navigation : Scenario
 
         View overlappedView2 = CreateOverlappedView (3, Pos.Center () + 10, Pos.Center () + 5);
 
-        // BUGBUG: F6 through nested tab groups doesn't work yet.
-#if NESTED_TABGROUPS
         var overlappedInOverlapped1 = CreateOverlappedView (4, 1, 4);
         overlappedView2.Add (overlappedInOverlapped1);
 
         var overlappedInOverlapped2 = CreateOverlappedView (5, 10, 7);
         overlappedView2.Add (overlappedInOverlapped2);
 
-#endif
+        CheckBox cb = new ()
+        {
+            X = Pos.AnchorEnd (),
+            Y = Pos.AnchorEnd (),
+            Title = "Checkbo_x"
+        };
+        overlappedView2.Add (cb);
 
         testFrame.Add (overlappedView1);
         testFrame.Add (overlappedView2);

UnitTests/View/Navigation/AdvanceFocusTests.cs

@@ -73,33 +73,35 @@ public class AdvanceFocusTests ()
     }
 
     [Fact]
-    public void AdvanceFocus_Compound_Subview ()
+    public void AdvanceFocus_Compound_Subview_TabStop ()
     {
+        TabBehavior behavior = TabBehavior.TabStop;
         var top = new View { Id = "top", CanFocus = true };
 
         var compoundSubview = new View
         {
             CanFocus = true,
-            Id = "compoundSubview"
+            Id = "compoundSubview",
+            TabStop = behavior
         };
-        var v1 = new View { Id = "v1", CanFocus = true };
-        var v2 = new View { Id = "v2", CanFocus = true };
-        var v3 = new View { Id = "v3", CanFocus = false };
+        var v1 = new View { Id = "v1", CanFocus = true, TabStop = behavior };
+        var v2 = new View { Id = "v2", CanFocus = true, TabStop = behavior };
+        var v3 = new View { Id = "v3", CanFocus = false, TabStop = behavior };
 
         compoundSubview.Add (v1, v2, v3);
 
         top.Add (compoundSubview);
 
         // Cycle through v1 & v2
-        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabStop);
+        top.AdvanceFocus (NavigationDirection.Forward, behavior);
         Assert.True (v1.HasFocus);
         Assert.False (v2.HasFocus);
         Assert.False (v3.HasFocus);
-        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabStop);
+        top.AdvanceFocus (NavigationDirection.Forward, behavior);
         Assert.False (v1.HasFocus);
         Assert.True (v2.HasFocus);
         Assert.False (v3.HasFocus);
-        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabStop);
+        top.AdvanceFocus (NavigationDirection.Forward, behavior);
         Assert.True (v1.HasFocus);
         Assert.False (v2.HasFocus);
         Assert.False (v3.HasFocus);
@@ -108,6 +110,7 @@ public class AdvanceFocusTests ()
         View otherSubview = new ()
         {
             CanFocus = true,
+            TabStop = behavior,
             Id = "otherSubview"
         };
 
@@ -118,15 +121,15 @@ public class AdvanceFocusTests ()
         Assert.False (v1.HasFocus);
 
         // Cycle through v1 & v2
-        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabStop);
+        top.AdvanceFocus (NavigationDirection.Forward, behavior);
         Assert.True (v1.HasFocus);
         Assert.False (v2.HasFocus);
         Assert.False (v3.HasFocus);
-        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabStop);
+        top.AdvanceFocus (NavigationDirection.Forward, behavior);
         Assert.False (v1.HasFocus);
         Assert.True (v2.HasFocus);
         Assert.False (v3.HasFocus);
-        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabStop);
+        top.AdvanceFocus (NavigationDirection.Forward, behavior);
         Assert.False (v1.HasFocus);
         Assert.False (v2.HasFocus);
         Assert.False (v3.HasFocus);
@@ -134,7 +137,7 @@ public class AdvanceFocusTests ()
         Assert.True (otherSubview.HasFocus);
 
         // v2 was previously focused down the compoundSubView focus chain
-        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabStop);
+        top.AdvanceFocus (NavigationDirection.Forward, behavior);
         Assert.False (v1.HasFocus);
         Assert.True (v2.HasFocus);
         Assert.False (v3.HasFocus);
@@ -142,6 +145,76 @@ public class AdvanceFocusTests ()
         top.Dispose ();
     }
 
+    [Fact]
+    public void AdvanceFocus_Compound_Subview_TabGroup ()
+    {
+        var top = new View { Id = "top", CanFocus = true, TabStop = TabBehavior.TabGroup };
+
+        var compoundSubview = new View
+        {
+            CanFocus = true,
+            Id = "compoundSubview",
+            TabStop = TabBehavior.TabGroup
+        };
+        var tabStopView = new View { Id = "tabStop", CanFocus = true, TabStop = TabBehavior.TabStop };
+        var tabGroupView1 = new View { Id = "tabGroup1", CanFocus = true, TabStop = TabBehavior.TabGroup };
+        var tabGroupView2 = new View { Id = "tabGroup2", CanFocus = true, TabStop = TabBehavior.TabGroup };
+
+        compoundSubview.Add (tabStopView, tabGroupView1, tabGroupView2);
+
+        top.Add (compoundSubview);
+        top.SetFocus ();
+        Assert.True (tabStopView.HasFocus);
+
+        // TabGroup should cycle to tabGroup1 then tabGroup2
+        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabGroup);
+        Assert.False (tabStopView.HasFocus);
+        Assert.True (tabGroupView1.HasFocus);
+        Assert.False (tabGroupView2.HasFocus);
+        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabGroup);
+        Assert.False (tabStopView.HasFocus);
+        Assert.False (tabGroupView1.HasFocus);
+        Assert.True (tabGroupView2.HasFocus);
+
+        // Add another TabGroup subview
+        View otherTabGroupSubview = new ()
+        {
+            CanFocus = true,
+            TabStop = TabBehavior.TabGroup,
+            Id = "otherTabGroupSubview"
+        };
+
+        top.Add (otherTabGroupSubview);
+
+        // Adding a focusable subview causes advancefocus
+        Assert.True (otherTabGroupSubview.HasFocus);
+        Assert.False (tabStopView.HasFocus);
+
+        // TagBroup navs to the other subview
+        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabGroup);
+        Assert.Equal (compoundSubview, top.Focused);
+        Assert.True (tabStopView.HasFocus); 
+
+        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabGroup);
+        Assert.Equal (compoundSubview, top.Focused);
+        Assert.True (tabGroupView1.HasFocus);
+
+        top.AdvanceFocus (NavigationDirection.Forward, TabBehavior.TabGroup);
+        Assert.Equal (compoundSubview, top.Focused);
+        Assert.True (tabGroupView2.HasFocus); 
+
+        // Now go backwards
+        top.AdvanceFocus (NavigationDirection.Backward, TabBehavior.TabGroup);
+        Assert.Equal (compoundSubview, top.Focused);
+        Assert.True (tabGroupView1.HasFocus);
+
+        top.AdvanceFocus (NavigationDirection.Backward, TabBehavior.TabGroup);
+        Assert.Equal (otherTabGroupSubview, top.Focused);
+        Assert.True (otherTabGroupSubview.HasFocus);
+
+        top.Dispose ();
+    }
+
     [Fact]
     public void AdvanceFocus_NoStop_And_CanFocus_True_No_Focus ()
     {

UnitTests/View/Navigation/NavigationTests.cs

@@ -206,7 +206,10 @@ public class NavigationTests (ITestOutputHelper _output) : TestsAllViews
 
                 break;
             case TabBehavior.TabGroup:
-                Application.OnKeyDown (Key.F6);
+                if (!Application.OnKeyDown (Key.F6))
+                {
+                    view.SetFocus ();
+                }
 
                 break;
             case null:
@@ -316,7 +319,6 @@ public class NavigationTests (ITestOutputHelper _output) : TestsAllViews
 
     // View.Focused - No subviews
     [Fact]
-    [Trait ("BUGBUG", "Fix in Issue #3444")]
     public void Focused_NoSubviews ()
     {
         var view = new View ();
@@ -324,47 +326,6 @@ public class NavigationTests (ITestOutputHelper _output) : TestsAllViews
 
         view.CanFocus = true;
         view.SetFocus ();
-        Assert.True (view.HasFocus);
-        Assert.Null (view.Focused); // BUGBUG: Should be view
-    }
-
-    [Fact]
-    public void FocusNearestView_Ensure_Focus_Ordered ()
-    {
-        Application.Top = Application.Current = new Toplevel ();
-
-        var win = new Window ();
-        var winSubview = new View { CanFocus = true, Text = "WindowSubview" };
-        win.Add (winSubview);
-        Application.Current.Add (win);
-
-        var frm = new FrameView ();
-        var frmSubview = new View { CanFocus = true, Text = "FrameSubview" };
-        frm.Add (frmSubview);
-        Application.Current.Add (frm);
-        Application.Current.SetFocus ();
-
-        Assert.Equal (winSubview, Application.Current.MostFocused);
-
-        Application.OnKeyDown (Key.Tab); // Move to the next TabStop. There is none. So we should stay.
-        Assert.Equal (winSubview, Application.Current.MostFocused);
-
-        Application.OnKeyDown (Key.F6);
-        Assert.Equal (frmSubview, Application.Current.MostFocused);
-
-        Application.OnKeyDown (Key.Tab);
-        Assert.Equal (frmSubview, Application.Current.MostFocused);
-
-        Application.OnKeyDown (Key.F6);
-        Assert.Equal (winSubview, Application.Current.MostFocused);
-
-        Application.OnKeyDown (Key.F6.WithShift);
-        Assert.Equal (frmSubview, Application.Current.MostFocused);
-
-        Application.OnKeyDown (Key.F6.WithShift);
-        Assert.Equal (winSubview, Application.Current.MostFocused);
-
-        Application.Current.Dispose ();
     }
 
     [Fact]