From 1815d9b129ebbe978baeeab9bd1ee3cbeb02e694 Mon Sep 17 00:00:00 2001
From: xiaoy312 <xiaoyao312@gmail.com>
Date: Mon, 6 Jan 2025 13:43:12 -0500
Subject: [PATCH] chore: fix tabbar indicator tests

---
 .../Tests/TabBarTests.cs                      | 48 +++++++++++--------
 .../Helpers/VisualTreeHelperEx.cs             |  9 ++--
 2 files changed, 35 insertions(+), 22 deletions(-)

diff --git a/src/Uno.Toolkit.RuntimeTests/Tests/TabBarTests.cs b/src/Uno.Toolkit.RuntimeTests/Tests/TabBarTests.cs
index 6f58fbcc3..0a2ef84be 100644
--- a/src/Uno.Toolkit.RuntimeTests/Tests/TabBarTests.cs
+++ b/src/Uno.Toolkit.RuntimeTests/Tests/TabBarTests.cs
@@ -157,15 +157,23 @@ public async Task SetSelectedIndex()
 		public async Task Verify_Indicator_Max_Size()
 		{
 			var source = Enumerable.Range(0, 3).Select(x => new TabBarItem { Content = x }).ToArray();
-			var indicator = new Border() { Height = 5, Background = new SolidColorBrush(Colors.Red) };
 			var SUT = new TabBar
 			{
 				ItemsSource = source,
-				SelectionIndicatorContent = indicator,
+				SelectionIndicatorContent = "asd",
+				SelectionIndicatorContentTemplate = XamlHelper.LoadXaml<DataTemplate>("""
+					<DataTemplate>
+						<Border x:Name="SutIndicator" Height="5" Background="Red" />
+					</DataTemplate>
+				"""),
 			};
 
 			await UnitTestUIContentHelperEx.SetContentAndWait(SUT);
 
+			var presenter = SUT.GetFirstDescendant<TabBarSelectionIndicatorPresenter>(x => x.Visibility == Visibility.Visible);
+			var indicator = presenter?.GetFirstDescendant<Border>("SutIndicator")!;
+			Assert.IsNotNull(indicator, "Failed to find Border#SutIndicator");
+
 			source[0].IsSelected = true;
 			await UnitTestsUIContentHelper.WaitForIdle();
 
@@ -183,37 +191,39 @@ public async Task Verify_Indicator_Max_Size()
 		}
 
 		[TestMethod]
-		[DataRow(Orientation.Horizontal, IndicatorTransitionMode.Snap, DisplayName = "Horizontal Snap")]
-		[DataRow(Orientation.Horizontal, IndicatorTransitionMode.Slide, DisplayName = "Horizontal Slide")]
-		[DataRow(Orientation.Vertical, IndicatorTransitionMode.Snap, DisplayName = "Vertical Snap")]
-		[DataRow(Orientation.Vertical, IndicatorTransitionMode.Slide, DisplayName = "Vertical Slide")]
+		[DataRow(Orientation.Horizontal, IndicatorTransitionMode.Snap)]
+		[DataRow(Orientation.Horizontal, IndicatorTransitionMode.Slide)]
+		[DataRow(Orientation.Vertical, IndicatorTransitionMode.Snap)]
+		[DataRow(Orientation.Vertical, IndicatorTransitionMode.Slide)]
 		public async Task Verify_Indicator_Transitions(Orientation orientation, IndicatorTransitionMode transitionMode)
 		{
 			const int NumItems = 3;
 			const double ItemSize = 100d;
+
 			var source = Enumerable.Range(0, NumItems).ToArray();
-			var indicator = new Border() { Background = new SolidColorBrush(Colors.Red) };
 			var SUT = new TabBar
 			{
 				Orientation = orientation,
 				ItemsSource = source,
-				SelectionIndicatorContent = indicator,
+				Width = orientation == Orientation.Horizontal ? ItemSize * NumItems : double.NaN,
+				Height = orientation == Orientation.Vertical ? ItemSize * NumItems : double.NaN,
+				SelectionIndicatorContent = "asd",
+				SelectionIndicatorContentTemplate = XamlHelper.LoadXaml<DataTemplate>($"""
+					<DataTemplate>
+						<Border x:Name="SutIndicator"
+								{(orientation == Orientation.Horizontal ? "Height" : "Width")}="5"
+								Background="Red" />
+					</DataTemplate>
+				"""),
 				SelectionIndicatorTransitionMode = transitionMode,
 			};
 
-			if (orientation == Orientation.Horizontal)
-			{
-				SUT.Width = ItemSize * NumItems;
-				indicator.Height = 5;
-			}
-			else
-			{
-				SUT.Height = ItemSize * NumItems;
-				indicator.Width = 5;
-			}
-
 			await UnitTestUIContentHelperEx.SetContentAndWait(SUT);
 
+			var presenter = SUT.GetFirstDescendant<TabBarSelectionIndicatorPresenter>(x => x.Visibility == Visibility.Visible);
+			var indicator = presenter?.GetFirstDescendant<Border>("SutIndicator")!;
+			Assert.IsNotNull(indicator, "Failed to find Border#SutIndicator");
+
 			for (int i = 0; i < NumItems; i++)
 			{
 				SUT.SelectedIndex = i;
diff --git a/src/Uno.Toolkit.UI/Helpers/VisualTreeHelperEx.cs b/src/Uno.Toolkit.UI/Helpers/VisualTreeHelperEx.cs
index cf9a2a7b6..d8c0b8d70 100644
--- a/src/Uno.Toolkit.UI/Helpers/VisualTreeHelperEx.cs
+++ b/src/Uno.Toolkit.UI/Helpers/VisualTreeHelperEx.cs
@@ -135,6 +135,10 @@ void Print(object o, int depth)
 			.OfType<T>()
 			.FirstOrDefault();
 
+		public static T? GetFirstDescendant<T>(this DependencyObject reference, string name) where T : FrameworkElement => GetDescendants(reference)
+			.OfType<T>()
+			.FirstOrDefault(x => x.Name == name);
+
 		/// <summary>
 		/// Returns the first descendant of a specified type that satisfies the <paramref name="predicate"/>.
 		/// </summary>
@@ -146,9 +150,8 @@ void Print(object o, int depth)
 			.OfType<T>()
 			.FirstOrDefault(predicate);
 
-		public static T GetFirstDescendantOrThrow<T>(this DependencyObject reference, string name) where T : FrameworkElement => GetDescendants(reference)
-			.OfType<T>()
-			.FirstOrDefault(x => x.Name == name) ??
+		public static T GetFirstDescendantOrThrow<T>(this DependencyObject reference, string name) where T : FrameworkElement =>
+			GetFirstDescendant<T>(reference, name) ??
 			throw new Exception($"Unable to find element: {typeof(T).Name}#{name}");
 
 		/// <summary>