From c2cf73ca9ea92e4a8d5da47839d37b553f1dd138 Mon Sep 17 00:00:00 2001
From: Paul Jenkins <paul@thewoodknight.com>
Date: Sun, 1 Mar 2026 08:24:05 +1100
Subject: [PATCH 1/3] Added a fallback image property to ImageBrushLoader

---
 AsyncImageLoader.Avalonia/ImageBrushLoader.cs | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/AsyncImageLoader.Avalonia/ImageBrushLoader.cs b/AsyncImageLoader.Avalonia/ImageBrushLoader.cs
index 2ce55b9..a936fa1 100644
--- a/AsyncImageLoader.Avalonia/ImageBrushLoader.cs
+++ b/AsyncImageLoader.Avalonia/ImageBrushLoader.cs
@@ -27,6 +27,14 @@ private static async void OnSourceChanged(ImageBrush imageBrush, AvaloniaPropert
         try {
             if (!string.IsNullOrWhiteSpace(newValue)) {
                 bitmap = await AsyncImageLoader.ProvideImageAsync(newValue!);
+            } else {
+                var fallback = GetFallbackImage(imageBrush);
+                if (fallback != null) {
+                    bitmap = fallback!;
+                    imageBrush.Source = bitmap;
+                    SetIsLoading(imageBrush, false);
+                    return;
+                }
             }
         }
         catch (Exception e) {
@@ -42,6 +50,17 @@ private static async void OnSourceChanged(ImageBrush imageBrush, AvaloniaPropert
     public static readonly AttachedProperty<string?> SourceProperty =
         AvaloniaProperty.RegisterAttached<ImageBrush, string?>("Source", typeof(ImageLoader));
 
+    public static readonly AttachedProperty<Bitmap?> FallbackImageProperty = 
+        AvaloniaProperty.RegisterAttached<ImageBrush, Bitmap?>("FallbackImage", typeof(Bitmap));
+
+    public static Bitmap? GetFallbackImage(ImageBrush element) {
+        return element.GetValue(FallbackImageProperty);
+    }
+
+    public static void SetFallbackImage(ImageBrush element, Bitmap? value) {
+        element.SetValue(FallbackImageProperty, value);
+    }
+
     public static string? GetSource(ImageBrush element) {
         return element.GetValue(SourceProperty);
     }

From 9561f01dae95fe469fe322e297660c7ad5f8470d Mon Sep 17 00:00:00 2001
From: Paul Jenkins <paul@thewoodknight.com>
Date: Mon, 2 Mar 2026 08:34:21 +1100
Subject: [PATCH 2/3] PR Fixes

Added XmlDoc
---
 AsyncImageLoader.Avalonia/ImageBrushLoader.cs | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/AsyncImageLoader.Avalonia/ImageBrushLoader.cs b/AsyncImageLoader.Avalonia/ImageBrushLoader.cs
index a936fa1..e171e95 100644
--- a/AsyncImageLoader.Avalonia/ImageBrushLoader.cs
+++ b/AsyncImageLoader.Avalonia/ImageBrushLoader.cs
@@ -50,13 +50,28 @@ private static async void OnSourceChanged(ImageBrush imageBrush, AvaloniaPropert
     public static readonly AttachedProperty<string?> SourceProperty =
         AvaloniaProperty.RegisterAttached<ImageBrush, string?>("Source", typeof(ImageLoader));
 
-    public static readonly AttachedProperty<Bitmap?> FallbackImageProperty = 
+    /// <summary>
+    /// Attached property that provides a fallback <see cref="Bitmap"/> to use when <see cref="SourceProperty"/> is null or empty.
+    /// </summary>
+    public static readonly AttachedProperty<Bitmap?> FallbackImageProperty =
         AvaloniaProperty.RegisterAttached<ImageBrush, Bitmap?>("FallbackImage", typeof(Bitmap));
 
+    /// <summary>
+    /// Gets the fallback <see cref="Bitmap"/> attached to the specified <see cref="ImageBrush"/>.
+    /// Returns <c>null</c> if no fallback image has been set.
+    /// </summary>
+    /// <param name="element">The <see cref="ImageBrush"/> to read the fallback image from.</param>
+    /// <returns>The fallback <see cref="Bitmap"/>, or <c>null</c> if none is set.</returns>
     public static Bitmap? GetFallbackImage(ImageBrush element) {
         return element.GetValue(FallbackImageProperty);
     }
 
+    /// <summary>
+    /// Sets the fallback <see cref="Bitmap"/> on the specified <see cref="ImageBrush"/>.
+    /// The fallback image is used when the <see cref="SourceProperty"/> value is null or empty.
+    /// </summary>
+    /// <param name="element">The <see cref="ImageBrush"/> to set the fallback image on.</param>
+    /// <param name="value">The <see cref="Bitmap"/> to use as the fallback</param>
     public static void SetFallbackImage(ImageBrush element, Bitmap? value) {
         element.SetValue(FallbackImageProperty, value);
     }

From 9e2d8cb8f739636c2ac5431bde04b5b06c5d4831 Mon Sep 17 00:00:00 2001
From: Paul Jenkins <paul@thewoodknight.com>
Date: Mon, 2 Mar 2026 08:43:48 +1100
Subject: [PATCH 3/3] PR fix: Checks for null of both bitmap and fallback
 before assigning

---
 AsyncImageLoader.Avalonia/ImageBrushLoader.cs | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/AsyncImageLoader.Avalonia/ImageBrushLoader.cs b/AsyncImageLoader.Avalonia/ImageBrushLoader.cs
index e171e95..9e7211c 100644
--- a/AsyncImageLoader.Avalonia/ImageBrushLoader.cs
+++ b/AsyncImageLoader.Avalonia/ImageBrushLoader.cs
@@ -25,17 +25,11 @@ private static async void OnSourceChanged(ImageBrush imageBrush, AvaloniaPropert
 
         Bitmap? bitmap = null;
         try {
-            if (!string.IsNullOrWhiteSpace(newValue)) {
+            if (!string.IsNullOrWhiteSpace(newValue))
                 bitmap = await AsyncImageLoader.ProvideImageAsync(newValue!);
-            } else {
-                var fallback = GetFallbackImage(imageBrush);
-                if (fallback != null) {
-                    bitmap = fallback!;
-                    imageBrush.Source = bitmap;
-                    SetIsLoading(imageBrush, false);
-                    return;
-                }
-            }
+
+            if (bitmap == null && GetFallbackImage(imageBrush) is Bitmap fallback)
+                bitmap = fallback;
         }
         catch (Exception e) {
             Logger?.Log("ImageBrushLoader", "ImageBrushLoader image resolution failed: {0}", e);