Clean-up Shadow internal part usage based on @Sergio0694 PR comments

Author: michael-hawker

Microsoft.Toolkit.Uwp.UI.Animations/Xaml/Abstract/ShadowAnimation{TValue,TKeyFrame}.cs

@@ -64,7 +64,7 @@ static AnimationBuilder ThrowArgumentNullException()
             if (Target is IAttachedShadow allShadows)
             {
                 // in this case we'll animate all the shadows being used.
-                foreach (var context in allShadows.GetElementContextEnumerable()) //// TODO: Find better way!!!
+                foreach (var context in allShadows.EnumerateElementContexts()) //// TODO: Find better way!!!
                 {
                     NormalizedKeyFrameAnimationBuilder<TKeyFrame>.Composition keyFrameBuilder = new(
                         explicitTarget,

Microsoft.Toolkit.Uwp.UI.Media/Shadows/AttachedCardShadow.cs

@@ -17,7 +17,7 @@ namespace Microsoft.Toolkit.Uwp.UI.Media
     /// <remarks>
     /// This shadow will not work on <see cref="FrameworkElement"/> which is directly clipping to its bounds (e.g. a <see cref="Windows.UI.Xaml.Controls.Border"/> using a <see cref="Windows.UI.Xaml.Controls.Control.CornerRadius"/>). An extra <see cref="Windows.UI.Xaml.Controls.Border"/> can instead be applied around the clipped border with the Shadow to create the desired effect. Most existing controls due to how they're templated will not encounter this behavior or require this workaround.
     /// </remarks>
-    public class AttachedCardShadow : AttachedShadowBase
+    public sealed class AttachedCardShadow : AttachedShadowBase
     {
         private const float MaxBlurRadius = 72;
         private static readonly TypedResourceKey<CompositionGeometricClip> ClipResourceKey = "Clip";
@@ -52,7 +52,7 @@ public double CornerRadius
         public override bool IsSupported => SupportsCompositionVisualSurface;
 
         /// <inheritdoc/>
-        protected override bool SupportsOnSizeChangedEvent => true;
+        protected internal override bool SupportsOnSizeChangedEvent => true;
 
         /// <inheritdoc/>
         protected override void OnPropertyChanged(AttachedShadowElementContext context, DependencyProperty property, object oldValue, object newValue)
@@ -145,7 +145,7 @@ protected override CompositionClip GetShadowClip(AttachedShadowElementContext co
         }
 
         /// <inheritdoc/>
-        protected override void OnSizeChanged(AttachedShadowElementContext context, Size newSize, Size previousSize)
+        protected internal override void OnSizeChanged(AttachedShadowElementContext context, Size newSize, Size previousSize)
         {
             var sizeAsVec2 = newSize.ToVector2();
 

Microsoft.Toolkit.Uwp.UI/Properties/AssemblyInfo.cs

@@ -0,0 +1,7 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.CompilerServices;
+
+[assembly: InternalsVisibleTo("Microsoft.Toolkit.Uwp.UI.Media")]

Microsoft.Toolkit.Uwp.UI/Shadows/AttachedDropShadow.cs

@@ -2,12 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
-using System.Collections.Generic;
 using System.Linq;
 using System.Numerics;
-using System.Text;
-using System.Threading.Tasks;
 using Windows.Foundation;
 using Windows.UI;
 using Windows.UI.Composition;
@@ -21,7 +17,7 @@ namespace Microsoft.Toolkit.Uwp.UI
     /// <summary>
     /// A helper to add a composition based drop shadow to a <see cref="FrameworkElement"/>.
     /// </summary>
-    public class AttachedDropShadow : AttachedShadowBase
+    public sealed class AttachedDropShadow : AttachedShadowBase
     {
         private const float MaxBlurRadius = 72;
 
@@ -121,7 +117,7 @@ private static void OnCastToPropertyChanged(DependencyObject d, DependencyProper
                     // Need to remove all old children from previous container if it's changed
                     if (prevContainer != null && prevContainer != shadow._container)
                     {
-                        foreach (var context in shadow.GetElementContextEnumerable())
+                        foreach (var context in shadow.EnumerateElementContexts())
                         {
                             if (context.IsInitialized &&
                                 prevContainer.Children.Contains(context.SpriteVisual))
@@ -132,7 +128,7 @@ private static void OnCastToPropertyChanged(DependencyObject d, DependencyProper
                     }
 
                     // Make sure all child shadows are hooked into container
-                    foreach (var context in shadow.GetElementContextEnumerable())
+                    foreach (var context in shadow.EnumerateElementContexts())
                     {
                         if (context.IsInitialized)
                         {
@@ -152,7 +148,7 @@ private void CastToElement_SizeChanged(object sender, SizeChangedEventArgs e)
         {
             // Don't use sender or 'e' here as related to container element not
             // element for shadow, grab values off context. (Also may be null from internal call.)
-            foreach (var context in GetElementContextEnumerable())
+            foreach (var context in EnumerateElementContexts())
             {
                 if (context.IsInitialized)
                 {

Microsoft.Toolkit.Uwp.UI/Shadows/AttachedShadowBase.cs

@@ -172,7 +172,7 @@ public AttachedShadowElementContext GetElementContext(FrameworkElement element)
         }
 
         /// <inheritdoc/>
-        public IEnumerable<AttachedShadowElementContext> GetElementContextEnumerable()
+        public IEnumerable<AttachedShadowElementContext> EnumerateElementContexts()
         {
             foreach (var kvp in ShadowElementContextTable)
             {

Microsoft.Toolkit.Uwp.UI/Shadows/AttachedShadowElementContext.cs

@@ -268,35 +268,35 @@ public T RemoveAndDisposeResource<T>(string key)
         /// </summary>
         /// <typeparam name="T">The type of the resource being added.</typeparam>
         /// <returns>The resource that was added</returns>
-        public T AddResource<T>(TypedResourceKey<T> key, T resource) => AddResource(key.Key, resource);
+        internal T AddResource<T>(TypedResourceKey<T> key, T resource) => AddResource(key.Key, resource);
 
         /// <summary>
         /// Retrieves a resource with the specified key and type if it exists
         /// </summary>
         /// <typeparam name="T">The type of the resource being retrieved.</typeparam>
         /// <returns>True if the resource exists, false otherwise</returns>
-        public bool TryGetResource<T>(TypedResourceKey<T> key, out T resource) => TryGetResource(key.Key, out resource);
+        internal bool TryGetResource<T>(TypedResourceKey<T> key, out T resource) => TryGetResource(key.Key, out resource);
 
         /// <summary>
         /// Retries a resource with the specified key and type
         /// </summary>
         /// <typeparam name="T">The type of the resource being retrieved.</typeparam>
         /// <returns>The resource if it exists or a default value.</returns>
-        public T GetResource<T>(TypedResourceKey<T> key) => GetResource<T>(key.Key);
+        internal T GetResource<T>(TypedResourceKey<T> key) => GetResource<T>(key.Key);
 
         /// <summary>
         /// Removes an existing resource with the specified key and type
         /// </summary>
         /// <typeparam name="T">The type of the resource being removed.</typeparam>
         /// <returns>The resource that was removed, if any</returns>
-        public T RemoveResource<T>(TypedResourceKey<T> key) => RemoveResource<T>(key.Key);
+        internal T RemoveResource<T>(TypedResourceKey<T> key) => RemoveResource<T>(key.Key);
 
         /// <summary>
         /// Removes an existing resource with the specified key and type, and <see cref="IDisposable.Dispose">disposes</see> it
         /// </summary>
         /// <typeparam name="T">The type of the resource being removed.</typeparam>
         /// <returns>The resource that was removed, if any</returns>
-        public T RemoveAndDisposeResource<T>(TypedResourceKey<T> key)
+        internal T RemoveAndDisposeResource<T>(TypedResourceKey<T> key)
             where T : IDisposable => RemoveAndDisposeResource<T>(key.Key);
 
         /// <summary>

Microsoft.Toolkit.Uwp.UI/Shadows/IAttachedShadow.cs

@@ -45,6 +45,6 @@ public interface IAttachedShadow
         /// Gets an enumeration over the current list of <see cref="AttachedShadowElementContext"/> of elements using this shared shadow definition.
         /// </summary>
         /// <returns>Enumeration of <see cref="AttachedShadowElementContext"/> objects.</returns>
-        IEnumerable<AttachedShadowElementContext> GetElementContextEnumerable();
+        IEnumerable<AttachedShadowElementContext> EnumerateElementContexts();
     }
 }

Microsoft.Toolkit/TypedResourceKey.cs renamed to Microsoft.Toolkit.Uwp.UI/Shadows/TypedResourceKey.cs

@@ -4,13 +4,13 @@
 
 using System;
 
-namespace Microsoft.Toolkit
+namespace Microsoft.Toolkit.Uwp.UI
 {
     /// <summary>
     /// A generic class that can be used to retrieve keyed resources of the specified type.
     /// </summary>
     /// <typeparam name="TValue">The <see cref="Type"/> of resource the <see cref="TypedResourceKey{TValue}"/> will retrieve.</typeparam>
-    public class TypedResourceKey<TValue>
+    internal sealed class TypedResourceKey<TValue>
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="TypedResourceKey{TValue}"/> class  with the specified key.