Move MauiBlazorBindingsElementManager to BlazorBindings.Core

src/BlazorBindings.Core/ElementManager.cs

@@ -9,8 +9,48 @@ namespace BlazorBindings.Core;
 /// parent/child relationships, so each must implement this given the constraints
 /// and requirements of their systems.
 /// </summary>
-public abstract class ElementManager
+public class ElementManager
 {
-    public abstract void AddChildElement(IElementHandler parentHandler, IElementHandler childHandler, int physicalSiblingIndex);
-    public abstract void RemoveChildElement(IElementHandler parentHandler, IElementHandler childHandler, int physicalSiblingIndex);
+    public virtual void AddChildElement(
+        IElementHandler parentHandler,
+        IElementHandler childHandler,
+        int physicalSiblingIndex)
+    {
+        if (childHandler is INonPhysicalChild nonPhysicalChild)
+        {
+            // If the child is a non-child container then we shouldn't try to add it to a parent.
+            // This is used in cases such as ModalContainer, which exists for the purposes of Blazor
+            // markup and is not represented in the Xamarin.Forms control hierarchy.
+
+            nonPhysicalChild.SetParent(parentHandler.TargetElement);
+            return;
+        }
+
+        if (parentHandler is not IContainerElementHandler parent)
+        {
+            throw new NotSupportedException($"Handler of type '{parentHandler.GetType().FullName}' representing element type " +
+                $"'{parentHandler.TargetElement?.GetType().FullName ?? "<null>"}' doesn't support adding a child " +
+                $"(child type is '{childHandler.TargetElement?.GetType().FullName}').");
+        }
+
+        parent.AddChild(childHandler.TargetElement, physicalSiblingIndex);
+    }
+
+    public virtual void RemoveChildElement(IElementHandler parentHandler, IElementHandler childHandler, int physicalSiblingIndex)
+    {
+        if (childHandler is INonPhysicalChild nonPhysicalChild)
+        {
+            nonPhysicalChild.RemoveFromParent(parentHandler.TargetElement);
+        }
+        else if (parentHandler is IContainerElementHandler parent)
+        {
+            parent.RemoveChild(childHandler.TargetElement, physicalSiblingIndex);
+        }
+        else
+        {
+            throw new NotSupportedException($"Handler of type '{parentHandler.GetType().FullName}' representing element type " +
+                $"'{parentHandler.TargetElement?.GetType().FullName ?? "<null>"}' doesn't support removing a child " +
+                $"(child type is '{childHandler.TargetElement?.GetType().FullName}').");
+        }
+    }
 }

src/BlazorBindings.Maui/IContainerElementHandler.cs → src/BlazorBindings.Core/IContainerElementHandler.cs

@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT license.
 
-namespace BlazorBindings.Maui;
+namespace BlazorBindings.Core;
 
 public interface IContainerElementHandler : IElementHandler
 {

src/BlazorBindings.Core/NativeComponentRenderer.cs

@@ -18,7 +18,7 @@ public NativeComponentRenderer(IServiceProvider serviceProvider, ILoggerFactory
     {
     }
 
-    protected abstract ElementManager CreateNativeControlManager();
+    protected virtual ElementManager CreateNativeControlManager() => new();
 
     internal ElementManager ElementManager => _elementManager ??= CreateNativeControlManager();
 

src/BlazorBindings.Maui/MauiBlazorBindingsRenderer.cs

@@ -53,11 +53,6 @@ protected override void HandleException(Exception exception)
         ExceptionDispatchInfo.Throw(exception);
     }
 
-    protected override ElementManager CreateNativeControlManager()
-    {
-        return new MauiBlazorBindingsElementManager();
-    }
-
     // It tries to return the Element as soon as it is available, therefore Component task might still be in progress.
     internal async Task<(object Element, Task<IComponent> Component)> GetElementFromRenderedComponent(Type componentType, Dictionary<string, object> parameters = null)
     {