[Android] SearchBar does not update colors on theme change - fix

src/Controls/src/Core/SearchBar/SearchBar.cs

@@ -3,6 +3,7 @@
 using System.ComponentModel;
 using System.Diagnostics;
 using System.Windows.Input;
+using Microsoft.Maui.ApplicationModel;
 using Microsoft.Maui.Controls.Internals;
 
 using Microsoft.Maui.Graphics;
@@ -115,6 +116,26 @@ public SearchBar()
 			_platformConfigurationRegistry = new Lazy<PlatformConfigurationRegistry<SearchBar>>(() => new PlatformConfigurationRegistry<SearchBar>(this));
 		}
 
+		private protected override void OnHandlerChangingCore(HandlerChangingEventArgs args)
+		{
+			base.OnHandlerChangingCore(args);
+
+			if (Application.Current == null)
+				return;
+
+			if (args.NewHandler == null || args.OldHandler is not null)
+				Application.Current.RequestedThemeChanged -= OnRequestedThemeChanged;
+			if (args.NewHandler != null && args.OldHandler == null)
+				Application.Current.RequestedThemeChanged += OnRequestedThemeChanged;
+		}
+
+		private void OnRequestedThemeChanged(object sender, AppThemeChangedEventArgs e)
+		{
+			OnPropertyChanged(nameof(PlaceholderColor));
+			OnPropertyChanged(nameof(TextColor));
+			OnPropertyChanged(nameof(CancelButtonColor));
+		}
+
 		ICommand ICommandElement.Command => SearchCommand;
 
 		object ICommandElement.CommandParameter => SearchCommandParameter;

src/Controls/tests/TestCases.HostApp/Issues/Issue30601.cs

@@ -0,0 +1,41 @@
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 30601, "[Android] SearchBar does not update colors on theme change", PlatformAffected.Android)]
+public class Issue30601 : ContentPage
+{
+	public Issue30601()
+	{
+		var searchBar3 = new SearchBar
+		{
+			Placeholder = "Placeholder with AppThemeBinding - red/green"
+		};
+		searchBar3.SetAppThemeColor(SearchBar.PlaceholderColorProperty, Colors.Red, Colors.Green);
+		this.SetAppThemeColor(BackgroundProperty, Colors.White, Colors.Black);
+
+		Content = new StackLayout
+		{
+			Children =
+				{
+					new SearchBar
+					{
+						Placeholder = "Placeholder - system's default"
+					},
+					new SearchBar
+					{
+						PlaceholderColor = Colors.Red,
+						Placeholder = "Placeholder - red"
+					},
+					searchBar3,
+					new Button
+					{
+						Text = "Change Theme",
+						AutomationId = "changeThemeButton",
+						Command= new Command(() =>
+						{
+							Application.Current!.UserAppTheme = Application.Current!.UserAppTheme != AppTheme.Dark ? AppTheme.Dark : AppTheme.Light;
+						})
+					}
+				}
+		};
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue30601.cs

@@ -0,0 +1,21 @@
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue30601 : _IssuesUITest
+{
+	public Issue30601(TestDevice testDevice) : base(testDevice) { }
+
+	public override string Issue => "[Android] SearchBar does not update colors on theme change";
+
+	[Test]
+	[Category(UITestCategories.SearchBar)]
+	public void SearchbarColorsShouldUpdate()
+	{
+		App.WaitForElement("changeThemeButton");
+		App.Tap("changeThemeButton");
+		VerifyScreenshot();
+	}
+}

src/Core/src/Handlers/SearchBar/SearchBarHandler.Android.cs

@@ -112,6 +112,7 @@ public static void MapCharacterSpacing(ISearchBarHandler handler, ISearchBar sea
 		public static void MapTextColor(ISearchBarHandler handler, ISearchBar searchBar)
 		{
 			handler.QueryEditor?.UpdateTextColor(searchBar);
+			handler.PlatformView?.UpdateTextColor(searchBar);
 		}
 
 		public static void MapIsTextPredictionEnabled(ISearchBarHandler handler, ISearchBar searchBar)

src/Core/src/Platform/Android/SearchViewExtensions.cs

@@ -1,6 +1,11 @@
-using Android.Content.Res;
+using System;
+using Android.Content.Res;
+using Android.Graphics;
+using Android.Graphics.Drawables;
 using Android.Text;
+using Android.Util;
 using Android.Widget;
+using static Android.Content.Res.Resources;
 using SearchView = AndroidX.AppCompat.Widget.SearchView;
 
 namespace Microsoft.Maui.Platform
@@ -21,22 +26,36 @@ public static void UpdatePlaceholderColor(this SearchView searchView, ISearchBar
 		{
 			editText ??= searchView.GetFirstChildOfType<EditText>();
 
-			if (editText == null)
+			if (editText is null)
 				return;
 
-			var placeholderTextColor = searchBar.PlaceholderColor;
-
-			if (placeholderTextColor == null)
-			{
-				editText.SetHintTextColor(defaultPlaceholderColor);
-			}
-			else
+			if (searchBar?.PlaceholderColor is Graphics.Color placeholderTextColor)
 			{
 				if (PlatformInterop.CreateEditTextColorStateList(editText.HintTextColors, placeholderTextColor.ToPlatform()) is ColorStateList c)
 				{
 					editText.SetHintTextColor(c);
 				}
 			}
+			else if (TryGetDefaultStateColor(searchView, Android.Resource.Attribute.TextColorHint, out var color))
+			{
+				editText.SetHintTextColor(color);
+
+				var searchMagIconImage = searchView.FindViewById<ImageView>(Resource.Id.search_mag_icon);
+				searchMagIconImage?.Drawable?.SetTint(color);
+			}
+		}
+
+		internal static void UpdateTextColor(this SearchView searchView, ITextStyle entry)
+		{
+			if (TryGetDefaultStateColor(searchView, Android.Resource.Attribute.TextColorPrimary, out var color) &&
+				searchView.GetFirstChildOfType<EditText>() is EditText editText)
+			{
+				if (entry.TextColor is null)
+					editText.SetTextColor(color);
+
+				var searchMagIconImage = searchView.FindViewById<ImageView>(Resource.Id.search_mag_icon);
+				searchMagIconImage?.Drawable?.SetTint(color);
+			}
 		}
 
 		public static void UpdateFont(this SearchView searchView, ISearchBar searchBar, IFontManager fontManager, EditText? editText = null)
@@ -108,12 +127,12 @@ public static void UpdateCancelButtonColor(this SearchView searchView, ISearchBa
 			{
 				var image = searchView.FindViewById<ImageView>(searchCloseButtonIdentifier);
 
-				if (image != null && image.Drawable != null)
+				if (image is not null && image.Drawable is Drawable drawable)
 				{
-					if (searchBar.CancelButtonColor != null)
-						image.Drawable.SetColorFilter(searchBar.CancelButtonColor, FilterMode.SrcIn);
-					else
-						image.Drawable.ClearColorFilter();
+					if (searchBar.CancelButtonColor is not null)
+						drawable.SetColorFilter(searchBar.CancelButtonColor, FilterMode.SrcIn);
+					else if (TryGetDefaultStateColor(searchView, Android.Resource.Attribute.TextColorPrimary, out var color))
+						drawable.SetColorFilter(color, FilterMode.SrcIn);
 				}
 			}
 		}
@@ -171,5 +190,28 @@ internal static void SetInputType(this SearchView searchView, ISearchBar searchB
 
 			editText.SetInputType(searchBar);
 		}
+
+		static bool TryGetDefaultStateColor(SearchView searchView, int attribute, out Color color)
+		{
+			color = default;
+
+			if (!OperatingSystem.IsAndroidVersionAtLeast(23))
+				return false;
+
+			if (searchView.Context?.Theme is not Theme theme)
+				return false;
+
+			int[] s_disabledState = [-Android.Resource.Attribute.StateEnabled];
+			int[] s_enabledState = [Android.Resource.Attribute.StateEnabled];
+
+			using var ta = theme.ObtainStyledAttributes([attribute]);
+			var cs = ta.GetColorStateList(0);
+			if (cs is null)
+				return false;
+
+			var state = searchView.Enabled ? s_enabledState : s_disabledState;
+			color = new Color(cs.GetColorForState(state, Color.Black));
+			return true;
+		}
 	}
 }