Merge pull request #11885 from unoplatform/dev/sb/imagebrush-bitmap-ios

fix: Ensure imagebrush's source is updated when set

src/Uno.UI.RuntimeTests/Helpers/ImageAssert.cs

@@ -65,6 +65,25 @@ public static partial class ImageAssert
 		Assert.Fail($"Expected '{ToArgbCode(expectedColor)}' in rectangle '{rect}'.");
 	}
 
+	/// <summary>
+	/// Asserts that a given screenshot does not have a specific color anywhere within a given rectangle.
+	/// </summary>
+	public static void DoesNotHaveColorInRectangle(RawBitmap screenshot, Rectangle rect, Color excludedColor, byte tolerance = 0, [CallerLineNumber] int line = 0)
+	{
+		var bitmap = screenshot;
+		for (var x = rect.Left; x < rect.Right; x++)
+		{
+			for (var y = rect.Top; y < rect.Bottom; y++)
+			{
+				var pixel = bitmap.GetPixel(x, y);
+				if (AreSameColor(excludedColor, pixel, tolerance, out _))
+				{
+					Assert.Fail($"Color '{ToArgbCode(excludedColor)}' was found at ({x}, {y}) in rectangle '{rect}'.");
+				}
+			}
+		}
+	}
+
 	private static void HasColorAtImpl(RawBitmap screenshot, int x, int y, Color expectedColor, byte tolerance, int line)
 	{
 		var bitmap = screenshot;

src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml_Media_Imaging/Given_BitmapSource.cs

@@ -8,9 +8,18 @@ using Windows.UI.Xaml.Controls;
 using Windows.UI.Xaml.Markup;
 using Windows.UI.Xaml.Media.Imaging;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System.Runtime.InteropServices.WindowsRuntime;
 using Private.Infrastructure;
 using Windows.Storage;
 using static Private.Infrastructure.TestServices;
+using Windows.UI.Xaml.Shapes;
+using Windows.UI.Xaml.Media;
+using Windows.UI;
+using Uno.UI.RuntimeTests.Helpers;
+using Uno.UI.RuntimeTests.Extensions;
+using Windows.Foundation.Metadata;
+using Windows.UI.Xaml;
+using System.Linq;
 
 namespace Uno.UI.RuntimeTests.Tests.Windows_UI_Xaml_Media_Imaging
 {
@@ -124,6 +133,64 @@ namespace Uno.UI.RuntimeTests.Tests.Windows_UI_Xaml_Media_Imaging
 		}
 #endif
 
+		[TestMethod]
+		[RunsOnUIThread]
+		public async Task When_WriteableBitmap_Assigned_With_Data_Present()
+		{
+			if (!ApiInformation.IsTypePresent("Windows.UI.Xaml.Media.Imaging.RenderTargetBitmap"))
+			{
+				Assert.Inconclusive(); // System.NotImplementedException: RenderTargetBitmap is not supported on this platform.;
+			}
+
+			var wb = new WriteableBitmap(20, 20);
+
+			var parent = new Border()
+			{
+				Width = 50,
+				Height = 50,
+				Background = new SolidColorBrush(Colors.Blue),
+			};
+
+			var rect = new Rectangle
+			{
+				Width = 20,
+				Height = 20,
+				VerticalAlignment = VerticalAlignment.Center,
+				HorizontalAlignment = HorizontalAlignment.Center,
+			};
+
+			parent.Child = rect;
+
+			WindowHelper.WindowContent = parent;
+
+			await WindowHelper.WaitForIdle();
+			await WindowHelper.WaitForLoaded(rect);
+
+			var bgraPixelData = Enumerable.Repeat<byte>(255, (int)wb.PixelBuffer.Length).ToArray();
+
+			using (Stream stream = wb.PixelBuffer.AsStream())
+			{
+				stream.Write(bgraPixelData, 0, bgraPixelData.Length);
+			}
+
+			rect.Fill = new ImageBrush
+			{
+				ImageSource = wb
+			};
+
+			await WindowHelper.WaitForIdle();
+
+			var renderer = new RenderTargetBitmap();
+			await WindowHelper.WaitForIdle();
+			await renderer.RenderAsync(parent);
+			var snapshot = await RawBitmap.From(renderer, rect);
+			var coords = parent.GetRelativeCoords(rect);
+			await WindowHelper.WaitForIdle();
+
+			ImageAssert.DoesNotHaveColorInRectangle(
+				snapshot, new System.Drawing.Rectangle((int)coords.X, (int)coords.Y, (int)coords.Width, (int)coords.Height), Colors.Blue);
+		}
+
 		private class Given_BitmapSource_Exception : Exception
 		{
 			public string Caller { get; }

src/Uno.UI/UI/Xaml/Media/Brush.iOSmacOS.cs

@@ -63,6 +63,8 @@ namespace Windows.UI.Xaml.Media
 			else if (b is ImageBrush imageBrush)
 			{
 				var disposables = new CompositeDisposable(5);
+				imageBrushCallback?.Invoke();
+
 				void ImageChanged(_Image _) => colorSetter(SolidColorBrushHelper.Transparent.Color);
 
 				imageBrush.ImageChanged += ImageChanged;