Revert "Make sure Popups do not attempt to take focus when they are shown (#16365)"

This reverts commit 80d73e4411.

native/Avalonia.Native/src/OSX/AvnView.mm

@@ -297,22 +297,7 @@
                             )
             )
             )
-    {
+        [self becomeFirstResponder];
-        WindowBaseImpl* windowBase = dynamic_cast<WindowBaseImpl*>(_parent.getRaw());
-        
-        if(windowBase != nullptr){
-            WindowBaseImpl* parent = windowBase->Parent;
-            
-            if(parent != nullptr){
-                auto parentWindow = parent->Window;
-                
-                [parentWindow makeFirstResponder:parent->View];
-            }
-        } else{
-            [self becomeFirstResponder];
-        }
-    }
-       
 
     if(_parent != nullptr)
     {

src/Avalonia.Native/PopupImpl.cs

@@ -8,6 +8,8 @@ namespace Avalonia.Native
     class PopupImpl : WindowBaseImpl, IPopupImpl
     {
         private readonly ITopLevelImpl _parent;
+        private readonly IAvnPopup _native;
+        private readonly AvaloniaNativeTextInputMethod _inputMethod;
 
         public PopupImpl(IAvaloniaNativeFactory factory,
             ITopLevelImpl parent) : base(factory)
@@ -16,7 +18,7 @@ namespace Avalonia.Native
             
             using (var e = new PopupEvents(this))
             {
-                Init(new MacOSTopLevelHandle(factory.CreatePopup(e)), factory.CreateScreens());
+                Init(new MacOSTopLevelHandle(_native = factory.CreatePopup(e)), factory.CreateScreens());
             }
             
             PopupPositioner = new ManagedPopupPositioner(new ManagedPopupPositionerPopupImplHelper(parent, MoveResize));
@@ -26,15 +28,10 @@ namespace Avalonia.Native
                 parent = popupImpl._parent;
             }
 
-            if (parent is WindowBaseImpl windowBaseImpl)
-            {
-                Native!.SetParent(windowBaseImpl.Native);
-            }
-            
             //Use the parent's input context to process events
             if (parent is TopLevelImpl topLevelImpl)
             {
-                InputMethod = topLevelImpl.InputMethod;
+                _inputMethod = topLevelImpl.InputMethod;
             }
         }
 
@@ -43,13 +40,6 @@ namespace Avalonia.Native
             base.Init(handle, screens);
         }
 
-        public override void Dispose()
-        {
-            Native!.SetParent(null);
-            
-            base.Dispose();
-        }
-
         private void MoveResize(PixelPoint position, Size size, double scaling)
         {
             Position = position;
@@ -81,6 +71,16 @@ namespace Avalonia.Native
             }
         }
 
+        public override void Show(bool activate, bool isDialog)
+        {
+            var parent = _parent;
+            while (parent is PopupImpl p) 
+                parent = p._parent;
+            if (parent is WindowImpl w)
+                w.Native.TakeFocusFromChildren();
+            base.Show(false, isDialog);
+        }
+
         public override IPopupImpl CreatePopup() => new PopupImpl(Factory, this);
 
         public void SetWindowManagerAddShadowHint(bool enabled)

src/Avalonia.Native/TopLevelImpl.cs

@@ -110,7 +110,7 @@ internal class TopLevelImpl : ITopLevelImpl, IFramebufferPlatformSurface
 
     public IAvnTopLevel? Native => _handle?.Native;
     public IPlatformHandle? Handle => _handle;
-    public AvaloniaNativeTextInputMethod? InputMethod { get; protected set; }
+    public AvaloniaNativeTextInputMethod? InputMethod { get; private set; }
     public Size ClientSize
     {
         get

src/Windows/Avalonia.Win32/PopupImpl.cs

@@ -22,6 +22,25 @@ namespace Avalonia.Win32
         {
             // Popups are always shown non-activated.
             UnmanagedMethods.ShowWindow(Handle.Handle, UnmanagedMethods.ShowWindowCommand.ShowNoActivate);
+
+            // We need to steal focus if it's held by a child window of our toplevel window
+            var parent = _parent;
+            while(parent != null)
+            {
+                if(parent is PopupImpl pi)
+                   parent = pi._parent;
+                else
+                    break;
+            }
+
+            if(parent == null)
+                return;
+
+            var focusOwner = UnmanagedMethods.GetFocus();
+            if (focusOwner != IntPtr.Zero &&
+                UnmanagedMethods.GetAncestor(focusOwner, UnmanagedMethods.GetAncestorFlags.GA_ROOT)
+                == parent.Handle?.Handle)
+                UnmanagedMethods.SetFocus(parent.Handle.Handle);
         }
 
         protected override bool ShouldTakeFocusOnClick => false;