Fixes Setting BackgroundColor to null does not actually changes BackgroundColor #22914 (#22917)

Jon2G · jsuarezruiz · mattleibow · PureWeen · commit 19402d377cb5 · 2025-06-16T17:05:56.000Z
* Fixes #22914 * Add tests Add tests for appium * Fix the build * Use VerifyScreenshot * @jsuarezruiz suggested changes --------- Co-authored-by: Javier Suárez <javiersuarezruiz@hotmail.com> Co-authored-by: Matthew Leibowitz <mattleibow@live.com>
diff --git a/src/Controls/tests/TestCases.HostApp/Issues/Issue22914.xaml b/src/Controls/tests/TestCases.HostApp/Issues/Issue22914.xaml
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ContentPage
+    x:Class="Maui.Controls.Sample.Issues.Issue22914"
+    xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml">
+    <VerticalStackLayout x:Name="VerticalStackLayout1" BackgroundColor="Orange">
+
+
+        <ContentView x:Name="ContentView1" BackgroundColor="Gray">
+            <Label Text="You should be able to read after tapping the button" TextColor="Gray" />
+        </ContentView>
+
+        <Label
+            x:Name="Label1"
+            BackgroundColor="Green"
+            HeightRequest="100"
+            Text="Sample label" />
+
+        <Button
+            x:Name="Tap1Button"
+            AutomationId="Tap1Button"
+            BackgroundColor="Red"
+            Text="Reset background color" />
+
+    </VerticalStackLayout>
+</ContentPage>
diff --git a/src/Controls/tests/TestCases.HostApp/Issues/Issue22914.xaml.cs b/src/Controls/tests/TestCases.HostApp/Issues/Issue22914.xaml.cs
@@ -0,0 +1,26 @@
+using Microsoft.Maui.Controls;
+using Microsoft.Maui.Controls.Xaml;
+
+namespace Maui.Controls.Sample.Issues
+{
+	[XamlCompilation(XamlCompilationOptions.Compile)]
+	[Issue(IssueTracker.Github, 22914, "Setting BackgroundColor to null does not actually changes BackgroundColor", PlatformAffected.iOS | PlatformAffected.Android)]
+	public partial class Issue22914 : ContentPage
+	{
+		public Issue22914()
+		{
+			InitializeComponent();
+
+			var tapCommand = new Command(buttonTapped);
+			this.Tap1Button.Command = tapCommand;
+		}
+
+		void buttonTapped()
+		{
+			this.Tap1Button.BackgroundColor = null;
+			this.ContentView1.BackgroundColor = null;
+			this.Label1.BackgroundColor = null;
+			this.VerticalStackLayout1.BackgroundColor = null;
+		}
+	}
+}
diff --git a/src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue22914.cs b/src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue22914.cs
@@ -0,0 +1,31 @@
+using System.Drawing;
+using NUnit.Framework;
+using NUnit.Framework.Legacy;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues
+{
+	public class Issue22914 : _IssuesUITest
+	{
+		const string ButtonId = "Tap1Button";
+
+		readonly string[] _expectedNullBackgroundColorIds = [ButtonId, "ContentView1", "Label1", "VerticalStackLayout1"];
+		
+		public Issue22914(TestDevice device) : base(device)
+		{
+		}
+
+		public override string Issue => "Setting BackgroundColor to null does not actually changes BackgroundColor";
+
+		[Test]
+		[Category(UITestCategories.ViewBaseTests)]
+		public void UpdateBackgroundColorToNull()
+		{
+			var tapAreaResult = App.WaitForElement(ButtonId, $"Timed out waiting for {ButtonId}");
+			tapAreaResult.Tap();
+
+			VerifyScreenshot("Issue22914Test");
+		}
+	}
+}
diff --git a/src/Core/src/Platform/Android/ViewExtensions.cs b/src/Core/src/Platform/Android/ViewExtensions.cs
@@ -300,7 +300,7 @@ internal static void UpdateBackground(this AView platformView, Paint? background
 						platformView.Background = drawable;
 				}
 			}
-			else if (platformView is LayoutViewGroup)
+			else if (platformView is not null)
 			{
 				platformView.Background = null;
 			}
diff --git a/src/Core/src/Platform/iOS/ViewExtensions.cs b/src/Core/src/Platform/iOS/ViewExtensions.cs
@@ -77,7 +77,7 @@ public static void UpdateBackground(this UIView platformView, Paint? paint, IBut
 
 			if (paint.IsNullOrEmpty())
 			{
-				if (platformView is LayoutView)
+				if (platformView is not null)
 					platformView.BackgroundColor = null;
 				else
 					return;

Original file line number	Diff line number	Diff line change
`@@ -300,7 +300,7 @@ internal static void UpdateBackground(this AView platformView, Paint? background`
`300`	`300`	`platformView.Background = drawable;`
`301`	`301`	`}`
`302`	`302`	`}`
`303`		`- else if (platformView is LayoutViewGroup)`
	`303`	`+ else if (platformView is not null)`
`304`	`304`	`{`
`305`	`305`	`platformView.Background = null;`
`306`	`306`	`}`
Original file line number	Diff line number	Diff line change
`@@ -77,7 +77,7 @@ public static void UpdateBackground(this UIView platformView, Paint? paint, IBut`
`77`	`77`
`78`	`78`	`if (paint.IsNullOrEmpty())`
`79`	`79`	`{`
`80`		`- if (platformView is LayoutView)`
	`80`	`+ if (platformView is not null)`
`81`	`81`	`platformView.BackgroundColor = null;`
`82`	`82`	`else`
`83`	`83`	`return;`