[net10.0] [iOS, Windows] Fix: Switch does not use the native default on color when OnColor is unset

src/Controls/tests/TestCases.HostApp/Issues/Issue29693.cs

@@ -0,0 +1,74 @@
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 29693, "The default native on color is not displayed when the Switch on color is not explicitly set", PlatformAffected.UWP)]
+public class Issue29693 : ContentPage
+{
+	public Issue29693()
+	{
+		var defaultOnSwitch = new Switch
+		{
+			IsToggled = true,
+			VerticalOptions = LayoutOptions.Center,
+			HorizontalOptions = LayoutOptions.Center,
+		};
+
+		var defaultOffSwitch = new Switch
+		{
+			VerticalOptions = LayoutOptions.Center,
+			HorizontalOptions = LayoutOptions.Center
+		};
+
+		var switchControl1 = new Switch
+		{
+			IsToggled = true,
+			VerticalOptions = LayoutOptions.Center,
+			HorizontalOptions = LayoutOptions.Center
+		};
+
+		var switchControl2 = new Switch
+		{
+			VerticalOptions = LayoutOptions.Center,
+			HorizontalOptions = LayoutOptions.Center
+		};
+
+		var button1 = new Button
+		{
+			Text = "Toggle Switch 3",
+			AutomationId = "button1",
+			VerticalOptions = LayoutOptions.Center,
+			HorizontalOptions = LayoutOptions.Center
+		};
+
+		var button2 = new Button
+		{
+			Text = "Toggle Switch 4",
+			AutomationId = "button2",
+			VerticalOptions = LayoutOptions.Center,
+			HorizontalOptions = LayoutOptions.Center,
+		};
+
+		button1.Clicked += (sender, e) =>
+		{
+			switchControl1.IsToggled = !switchControl1.IsToggled;
+		};
+
+		button2.Clicked += (sender, e) =>
+		{
+			switchControl2.IsToggled = !switchControl2.IsToggled;
+		};
+
+		var verticalStackLayout = new VerticalStackLayout()
+		{
+			Spacing = 20,
+			Padding = new Thickness(20),
+		};
+		verticalStackLayout.Add(defaultOnSwitch);
+		verticalStackLayout.Add(defaultOffSwitch);
+		verticalStackLayout.Add(switchControl1);
+		verticalStackLayout.Add(switchControl2);
+		verticalStackLayout.Add(button1);
+		verticalStackLayout.Add(button2);
+
+		Content = verticalStackLayout;
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue29693.cs

@@ -0,0 +1,24 @@
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue29693 : _IssuesUITest
+{
+	public override string Issue => "The default native on color is not displayed when the Switch on color is not explicitly set";
+
+	public Issue29693(TestDevice device)
+	: base(device)
+	{ }
+
+	[Test]
+	[Category(UITestCategories.Switch)]
+	public void VerifySwitchDefaultColors()
+	{
+		App.WaitForElement("button1");
+		App.Tap("button1");
+		App.Tap("button2");
+		VerifyScreenshot();
+	}
+}

src/Core/src/Platform/Android/SwitchExtensions.cs

@@ -13,17 +13,23 @@ public static void UpdateTrackColor(this ASwitch aSwitch, ISwitch view)
 			var trackColor = view.TrackColor;
 
 			if (trackColor is not null)
+			{
 				aSwitch.TrackDrawable?.SetColorFilter(trackColor, FilterMode.SrcAtop);
+			}
 			else
+			{
 				aSwitch.TrackDrawable?.ClearColorFilter();
+			}
 		}
 
 		public static void UpdateThumbColor(this ASwitch aSwitch, ISwitch view)
 		{
 			var thumbColor = view.ThumbColor;
 
-			if (thumbColor != null)
+			if (thumbColor is not null)
+			{
 				aSwitch.ThumbDrawable?.SetColorFilter(thumbColor, FilterMode.SrcAtop);
+			}
 		}
 
 		public static Drawable? GetDefaultSwitchTrackDrawable(this ASwitch aSwitch) =>

src/Core/src/Platform/Windows/SwitchExtensions.cs

@@ -8,46 +8,76 @@ public static class SwitchExtensions
 	{
 		public static void UpdateIsToggled(this ToggleSwitch toggleSwitch, ISwitch view)
 		{
-			if (toggleSwitch != null)
+			if (toggleSwitch is not null)
 			{
 				toggleSwitch.IsOn = view?.IsOn ?? false;
 			}
 		}
 
+		static readonly string[] toggleSwitchOnKeys =
+		{
+			"ToggleSwitchFillOn",
+			"ToggleSwitchFillOnPointerOver",
+			"ToggleSwitchFillOnPressed",
+			"ToggleSwitchFillOnDisabled"
+		};
+
+		static readonly string[] toggleSwitchOffKeys =
+		{
+			"ToggleSwitchFillOff",
+			"ToggleSwitchFillOffPointerOver",
+			"ToggleSwitchFillOffPressed",
+			"ToggleSwitchFillOffDisabled"
+		};
+
 		public static void UpdateTrackColor(this ToggleSwitch toggleSwitch, ISwitch view)
 		{
-			if (toggleSwitch == null)
+			if (toggleSwitch is null)
 			{
 				return;
 			}
 
-			var trackColor = view.TrackColor?.ToPlatform() ?? new SolidColorBrush(Color.FromArgb(6, 0, 0, 0));
+			var trackColor = view.TrackColor?.ToPlatform();
+
+			if (trackColor is not null)
+			{
+				if (view.IsOn)
+				{
+					toggleSwitch.Resources.SetValueForAllKey(toggleSwitchOnKeys, trackColor);
+				}
+				else
+				{
+					toggleSwitch.Resources.SetValueForAllKey(toggleSwitchOffKeys, trackColor);
+				}
+			}
+			else
+			{
+				if (view.IsOn)
+				{
+					toggleSwitch.Resources.RemoveKeys(toggleSwitchOnKeys);
+				}
+				else
+				{
+					toggleSwitch.Resources.RemoveKeys(toggleSwitchOffKeys);
+				}
+			}
 
-			toggleSwitch.TryUpdateResource(
-					trackColor,
-					"ToggleSwitchFillOn",
-					"ToggleSwitchFillOnPointerOver",
-					"ToggleSwitchFillOnPressed",
-					"ToggleSwitchFillOnDisabled",
-					"ToggleSwitchFillOff",
-					"ToggleSwitchFillOffPointerOver",
-					"ToggleSwitchFillOffPressed",
-					"ToggleSwitchFillOffDisabled");
+			toggleSwitch.RefreshThemeResources();
 		}
 
 		public static void UpdateThumbColor(this ToggleSwitch toggleSwitch, ISwitch view)
 		{
-			if (toggleSwitch == null)
+			if (toggleSwitch is null)
 			{
 				return;
 			}
 
-			if (view.ThumbColor == null)
+			if (view.ThumbColor is null)
 			{
 				return;
 			}
 
-			if (view.ThumbColor != null)
+			if (view.ThumbColor is not null)
 			{
 				toggleSwitch.TryUpdateResource(
 					view.ThumbColor.ToPlatform(),

src/Core/src/Platform/iOS/SwitchExtensions.cs

@@ -14,26 +14,46 @@ public static void UpdateIsOn(this UISwitch uiSwitch, ISwitch view)
 
 		public static void UpdateTrackColor(this UISwitch uiSwitch, ISwitch view)
 		{
-			if (view == null)
+			if (view is null)
+			{
 				return;
+			}
 
 			var uIView = GetTrackSubview(uiSwitch);
 
 			if (uIView is null)
+			{
 				return;
+			}
+
+			var trackColor = view.TrackColor?.ToPlatform();
 
-			if (view.TrackColor is not null)
+			if (view.IsOn)
 			{
-				uiSwitch.OnTintColor = view.TrackColor.ToPlatform();
-				uIView.BackgroundColor = uiSwitch.OnTintColor;
+				if (trackColor is not null)
+				{
+					uiSwitch.OnTintColor = trackColor;
+					uIView.BackgroundColor = trackColor;
+				}
+				else
+				{
+					uiSwitch.OnTintColor = null;
+					uIView.BackgroundColor = null;
+				}
 			}
-
 			else
 			{
-				// iOS 13+ uses the UIColor.SecondarySystemFill to support Light and Dark mode
-				// else, use the RGBA equivalent of UIColor.SecondarySystemFill in Light mode
-				uiSwitch.OnTintColor = OperatingSystem.IsIOSVersionAtLeast(13) ? UIColor.SecondarySystemFill : DefaultBackgroundColor;
-				uIView.BackgroundColor = uiSwitch.OnTintColor;
+				if (trackColor is not null)
+				{
+					uIView.BackgroundColor = trackColor;
+				}
+				else
+				{
+					// iOS 13+ uses the UIColor.SecondarySystemFill to support Light and Dark mode
+					// else, use the RGBA equivalent of UIColor.SecondarySystemFill in Light mode
+					var fallbackColor = OperatingSystem.IsIOSVersionAtLeast(13) ? UIColor.SecondarySystemFill : DefaultBackgroundColor;
+					uIView.BackgroundColor = fallbackColor;
+				}
 			}
 		}