Move some input handling out of TopLevel

src/Avalonia.Controls/PresentationSource/PresentationSource.Input.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Threading;
+using Avalonia.Diagnostics;
+using Avalonia.Input;
+using Avalonia.Input.Raw;
+using Avalonia.Logging;
+using Avalonia.Platform;
+using Avalonia.Threading;
+
+namespace Avalonia.Controls;
+
+internal partial class PresentationSource
+{
+    /// <summary>
+    /// Handles input from <see cref="ITopLevelImpl.Input"/>.
+    /// </summary>
+    /// <param name="e">The event args.</param>
+    private void HandleInputCore(object state)
+    {
+        using var _ = Diagnostic.BeginLayoutInputPass();
+
+        var e = (RawInputEventArgs)state!;
+        if (e is RawPointerEventArgs pointerArgs)
+        {
+            var hitTestElement = RootElement.InputHitTest(pointerArgs.Position, enabledElementsOnly: false);
+
+            pointerArgs.InputHitTestResult = (hitTestElement, FirstEnabledAncestor(hitTestElement));
+        }
+
+        _inputManager?.ProcessInput(e);
+    }
+
+    private SendOrPostCallback _handleInputCore;
+    
+    private void HandleInput(RawInputEventArgs e)
+    {
+        if (PlatformImpl != null)
+        {
+            Dispatcher.UIThread.Send(_handleInputCore, e);
+        }
+        else
+        {
+            Logger.TryGet(LogEventLevel.Warning, LogArea.Control)?.Log(
+                this,
+                "PlatformImpl is null, couldn't handle input.");
+        }
+    }
+    
+    
+    private static IInputElement? FirstEnabledAncestor(IInputElement? hitTestElement)
+    {
+        var candidate = hitTestElement;
+        while (candidate?.IsEffectivelyEnabled == false)
+        {
+            candidate = (candidate as Visual)?.VisualParent as IInputElement;
+        }
+        return candidate;
+    }
+}

src/Avalonia.Controls/PresentationSource/PresentationSource.cs

@@ -9,7 +9,7 @@ namespace Avalonia.Controls;
 
 internal partial class PresentationSource : IPresentationSource, IDisposable
 {
-    public ITopLevelImpl PlatformImpl { get; }
+    public ITopLevelImpl? PlatformImpl { get; private set; }
     private readonly PointerOverPreProcessor? _pointerOverPreProcessor;
     private readonly IDisposable? _pointerOverPreProcessorSubscription;
     private readonly IInputManager? _inputManager;
@@ -21,9 +21,14 @@ internal partial class PresentationSource : IPresentationSource, IDisposable
     {
         RootVisual = rootVisual;
         PlatformImpl = platformImpl;
-    
 
+    
         _inputManager = TryGetService<IInputManager>(dependencyResolver);
+        _handleInputCore = HandleInputCore;
+        
+        PlatformImpl.SetInputRoot(this);
+        PlatformImpl.Input = HandleInput;
+        
         _pointerOverPreProcessor = new PointerOverPreProcessor(this);
         _pointerOverPreProcessorSubscription = _inputManager?.PreProcess.Subscribe(_pointerOverPreProcessor);
     }
@@ -63,6 +68,7 @@ internal partial class PresentationSource : IPresentationSource, IDisposable
 
     public void Dispose()
     {
+        PlatformImpl = null;
         _pointerOverPreProcessor?.OnCompleted();
         _pointerOverPreProcessorSubscription?.Dispose();
     }
@@ -96,7 +102,7 @@ internal partial class PresentationSource : IPresentationSource, IDisposable
     }
 
     // TODO: Make popup positioner to use PresentationSource internally rather than TopLevel
-    public PixelPoint? GetLastPointerPosition(TopLevel topLevel)
+    public PixelPoint? GetLastPointerPosition(Visual topLevel)
     {
         return _pointerOverPreProcessor?.LastPosition;
     }

src/Avalonia.Controls/TopLevel.cs

@@ -212,11 +212,9 @@ namespace Avalonia.Controls
 
             Renderer = new CompositingRenderer(this, impl.Compositor, () => PlatformImpl.Surfaces ?? []);
             Renderer.SceneInvalidated += SceneInvalidated;
-
-            impl.SetInputRoot(_source);
+            
 
             impl.Closed = HandleClosed;
-            impl.Input = HandleInput;
             impl.Paint = HandlePaint;
             impl.Resized = HandleResized;
             impl.ScalingChanged = HandleScalingChanged;
@@ -815,48 +813,6 @@ namespace Avalonia.Controls
             return result;
         }
 
-        /// <summary>
-        /// Handles input from <see cref="ITopLevelImpl.Input"/>.
-        /// </summary>
-        /// <param name="e">The event args.</param>
-        private void HandleInput(RawInputEventArgs e)
-        {
-            if (PlatformImpl != null)
-            {
-                Dispatcher.UIThread.Send(static state =>
-                {
-                    using var _ = Diagnostic.BeginLayoutInputPass();
-
-                    var (topLevel, e) = (ValueTuple<TopLevel, RawInputEventArgs>)state!;
-                    if (e is RawPointerEventArgs pointerArgs)
-                    {
-                        var hitTestElement = topLevel.InputHitTest(pointerArgs.Position, enabledElementsOnly: false);
-
-                        pointerArgs.InputHitTestResult = (hitTestElement, FirstEnabledAncestor(hitTestElement));
-                    }
-
-                    topLevel._inputManager?.ProcessInput(e);
-                }, (this, e));
-            }
-            else
-            {
-                Logger.TryGet(LogEventLevel.Warning, LogArea.Control)?.Log(
-                    this,
-                    "PlatformImpl is null, couldn't handle input.");
-            }
-        }
-
-        private static IInputElement? FirstEnabledAncestor(IInputElement? hitTestElement)
-        {
-            var candidate = hitTestElement;
-            while (candidate?.IsEffectivelyEnabled == false)
-            {
-                candidate = (candidate as Visual)?.VisualParent as IInputElement;
-            }
-
-            return candidate;
-        }
-
         private void GlobalActualThemeVariantChanged(object? sender, EventArgs e)
         {
             SetValue(ActualThemeVariantProperty, ((IThemeVariantHost)sender!).ActualThemeVariant, BindingPriority.Template);