Inherit ResourceInclude from the MergeResourceInclude

src/Markup/Avalonia.Markup.Xaml/Styling/MergeResourceInclude.cs

@@ -2,6 +2,8 @@
 using System.Diagnostics.CodeAnalysis;
 using Avalonia.Controls;
 
+#nullable enable
+
 namespace Avalonia.Markup.Xaml.Styling;
 
 /// <summary>
@@ -12,68 +14,13 @@ namespace Avalonia.Markup.Xaml.Styling;
 /// When used in runtime, this type behaves like <see cref="ResourceInclude"/>.  
 /// </remarks>
 [RequiresUnreferencedCode(TrimmingMessages.StyleResourceIncludeRequiresUnreferenceCodeMessage)]
-public class MergeResourceInclude : IResourceProvider
+public class MergeResourceInclude : ResourceInclude
 {
-    private readonly IServiceProvider _serviceProvider;
+    public MergeResourceInclude(Uri? baseUri) : base(baseUri)
-    private readonly Uri? _baseUri;
-    private IResourceDictionary? _loaded;
-    private bool _isLoading;
-
-    /// <summary>
-    /// Initializes a new instance of the <see cref="ResourceInclude"/> class.
-    /// </summary>
-    /// <param name="serviceProvider">The XAML service provider.</param>
-    public MergeResourceInclude(IServiceProvider serviceProvider)
-    {
-        _serviceProvider = serviceProvider;
-        _baseUri = serviceProvider.GetContextBaseUri();
-    }
-
-    /// <summary>
-    /// Gets the loaded resource dictionary.
-    /// </summary>
-    public IResourceDictionary Loaded
-    {
-        get
-        {
-            if (_loaded == null)
-            {
-                _isLoading = true;
-                var source = Source ?? throw new InvalidOperationException("MergeResourceInclude.Source must be set.");
-                _loaded = (IResourceDictionary)AvaloniaXamlLoader.Load(_serviceProvider, source, _baseUri);
-                _isLoading = false;
-            }
-
-            return _loaded;
-        }
-    }
-
-    public IResourceHost? Owner => Loaded.Owner;
-
-    /// <summary>
-    /// Gets or sets the source URL.
-    /// </summary>
-    public Uri? Source { get; set; }
-
-    bool IResourceNode.HasResources => Loaded.HasResources;
-
-    public event EventHandler? OwnerChanged
     {
-        add => Loaded.OwnerChanged += value;
-        remove => Loaded.OwnerChanged -= value;
     }
 
-    bool IResourceNode.TryGetResource(object key, out object? value)
+    public MergeResourceInclude(IServiceProvider serviceProvider) : base(serviceProvider)
     {
-        if (!_isLoading)
-        {
-            return Loaded.TryGetResource(key, out value);
-        }
-
-        value = null;
-        return false;
     }
-
-    void IResourceProvider.AddOwner(IResourceHost owner) => Loaded.AddOwner(owner);
-    void IResourceProvider.RemoveOwner(IResourceHost owner) => Loaded.RemoveOwner(owner);
 }