Fixed Editor HorizontalTextAlignment does not update at run time

src/Controls/tests/DeviceTests/Elements/Editor/EditorTests.iOS.cs

@@ -105,6 +105,52 @@ await CreateHandlerAndAddToWindow(contentPage, async () =>
 					Assert.Equal(expectedFontFamily, placeholderLabel?.Font?.FamilyName);
 				});
 			}
+
+			[Fact]
+			public async Task PlaceholderHorizontalTextAlignment()
+			{
+				EnsureHandlerCreated(builder =>
+				{
+					builder.ConfigureMauiHandlers(handlers =>
+					{
+						handlers.AddHandler(typeof(Editor), typeof(EditorHandler));
+					});
+				});
+
+				var horizontalEndAlignment = TextAlignment.End;
+				var horizontalCenterAlignment = TextAlignment.Center;
+				var horizontalStartAlignment = TextAlignment.Start;
+
+				var editor = new Editor
+				{
+					Placeholder = "This is a placeholder"
+				};
+
+				ContentPage contentPage = new ContentPage()
+				{
+					Content = new VerticalStackLayout()
+					{
+						editor
+					}
+				};
+
+				await CreateHandlerAndAddToWindow(contentPage, async () =>
+				{
+					await AssertEventually(() => editor.IsVisible);
+					var handler = CreateHandler<EditorHandler>(editor);
+					var platformControl = GetPlatformControl(handler);
+
+					var placeholderLabel = handler.PlatformView.Subviews.OfType<UIKit.UILabel>().FirstOrDefault();
+
+					editor.HorizontalTextAlignment = horizontalCenterAlignment;
+					Assert.Equal(UIKit.UITextAlignment.Center, placeholderLabel?.TextAlignment);
+					editor.HorizontalTextAlignment = horizontalEndAlignment;
+					Assert.Equal(UIKit.UITextAlignment.Right, placeholderLabel?.TextAlignment);
+					editor.HorizontalTextAlignment = horizontalStartAlignment;
+					Assert.Equal(UIKit.UITextAlignment.Left, placeholderLabel?.TextAlignment);
+
+				});
+			}
 		}
 
 		//src/Compatibility/Core/tests/iOS/FlowDirectionTests.cs

src/Controls/tests/TestCases.HostApp/Issues/Issue10987.cs

@@ -0,0 +1,73 @@
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 10987, "Editor HorizontalTextAlignment Does not Works.", PlatformAffected.All)]
+public class Issue10987 : TestContentPage
+{
+	Editor lTReditor, rTLeditor;
+	Button updateAlignmentButton, resetAlignmentButton;
+	protected override void Init()
+	{
+
+		updateAlignmentButton = CreateButton("UpdateAlignmentButton", "Update alignment");
+		resetAlignmentButton = CreateButton("ResetAlignmentButton", "Reset alignment");
+
+		updateAlignmentButton.Clicked += OnUpdateAlignmentButtonClicked;
+		resetAlignmentButton.Clicked += OnResetAlignmentButtonClicked;
+
+		lTReditor = CreateEditor("LTREditor", "placeholder text", FlowDirection.LeftToRight);
+		rTLeditor = CreateEditor("RTLEditor", "placeholder text", FlowDirection.RightToLeft);
+
+		Content = new VerticalStackLayout
+		{
+			Spacing = 25,
+			VerticalOptions = LayoutOptions.Center,
+			Children =
+				{
+					updateAlignmentButton,
+					resetAlignmentButton,
+					lTReditor,
+					rTLeditor
+				}
+		};
+	}
+
+	Button CreateButton(string automationId, string text)
+	{
+		Button button = new Button();
+		button.AutomationId = automationId;
+		button.Text = text;
+		return button;
+	}
+
+	Editor CreateEditor(string automationId, string placeholderText, FlowDirection flowDirection)
+	{
+		Editor editor = new Editor();
+		editor.AutomationId = automationId;
+		editor.BackgroundColor = Colors.LightBlue;
+		editor.Placeholder = placeholderText;
+		editor.HeightRequest = 250;
+		editor.WidthRequest = 220;
+		editor.FlowDirection = flowDirection;
+		return editor;
+	}
+
+	private void OnResetAlignmentButtonClicked(object sender, EventArgs e)
+	{
+		lTReditor.VerticalTextAlignment = TextAlignment.Start;
+		lTReditor.HorizontalTextAlignment = TextAlignment.Start;
+		lTReditor.Unfocus();
+
+		rTLeditor.VerticalTextAlignment = TextAlignment.Start;
+		rTLeditor.HorizontalTextAlignment = TextAlignment.Start;
+		rTLeditor.Unfocus();
+	}
+
+	private void OnUpdateAlignmentButtonClicked(object sender, EventArgs e)
+	{
+		lTReditor.VerticalTextAlignment = TextAlignment.End;
+		lTReditor.HorizontalTextAlignment = TextAlignment.End;
+
+		rTLeditor.VerticalTextAlignment = TextAlignment.End;
+		rTLeditor.HorizontalTextAlignment = TextAlignment.End;
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue10987.cs

@@ -0,0 +1,39 @@
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue10987 : _IssuesUITest
+{
+	const string LTREditor = "LTREditor";
+	const string RTLEditor = "RTLEditor";
+	public Issue10987(TestDevice device) : base(device) { }
+
+	public override string Issue => "Editor HorizontalTextAlignment Does not Works.";
+
+	[Test]
+	[Category(UITestCategories.Editor)]
+	public void EditorPlaceholderRuntimeTextAlignmentChanged()
+	{
+		App.WaitForElement(RTLEditor);
+		App.Tap("UpdateAlignmentButton");
+		VerifyScreenshot();
+	}
+
+	[Test]
+	[Category(UITestCategories.Editor)]
+	public void EditorRuntimeTextAlignmentChanged()
+	{
+		//To make sure editor is focused in mac platform
+		App.Tap(LTREditor);
+		App.EnterText(LTREditor, "Editor Text");
+		App.WaitForElement(RTLEditor);
+		App.EnterText(RTLEditor, "RTL Editor");
+#if IOS
+		var app = App as AppiumApp;
+		KeyboardScrolling.HideKeyboard(app!, app!.Driver, true);
+#endif
+		App.Tap("ResetAlignmentButton");
+		VerifyScreenshot();
+	}
+}

src/Core/src/Handlers/Editor/EditorHandler.Android.cs

@@ -16,8 +16,8 @@ protected override MauiAppCompatEditText CreatePlatformView()
 			var editText = new MauiAppCompatEditText(Context)
 			{
 				ImeOptions = ImeAction.Done,
-				Gravity = GravityFlags.Top,
 				TextAlignment = global::Android.Views.TextAlignment.ViewStart,
+				Gravity = GravityFlags.Top,
 			};
 
 			editText.SetSingleLine(false);

src/Core/src/Platform/Android/TextAlignmentExtensions.cs

@@ -12,12 +12,9 @@ public static class TextAlignmentExtensions
 
 		internal static void UpdateHorizontalAlignment(this EditText view, TextAlignment alignment, AGravityFlags orMask = AGravityFlags.NoGravity)
 		{
-			if (!Rtl.IsSupported)
-			{
-				view.Gravity = (view.Gravity & ~HorizontalGravityMask) | alignment.ToHorizontalGravityFlags() | orMask;
-			}
-			else
-				view.TextAlignment = alignment.ToTextAlignment();
+			// The text alignment does not work at runtime, so we also need to update the gravity.
+			view.TextAlignment = alignment.ToTextAlignment();
+			view.Gravity = (view.Gravity & ~HorizontalGravityMask) | alignment.ToHorizontalGravityFlags() | orMask;
 		}
 
 		public static void UpdateVerticalAlignment(this EditText view, TextAlignment alignment, AGravityFlags orMask = AGravityFlags.NoGravity)

src/Core/src/Platform/iOS/MauiTextView.cs

@@ -13,6 +13,7 @@ public class MauiTextView : UITextView, IUIViewLifeCycleEvents
 		[UnconditionalSuppressMessage("Memory", "MEM0002", Justification = "Proven safe in test: MemoryTests.HandlerDoesNotLeak")]
 		readonly MauiLabel _placeholderLabel;
 		nfloat? _defaultPlaceholderSize;
+		TextAlignment _verticalTextAlignment;
 
 		public MauiTextView()
 		{
@@ -34,6 +35,19 @@ public override void WillMoveToWindow(UIWindow? window)
 			base.WillMoveToWindow(window);
 		}
 
+		public override UITextAlignment TextAlignment
+		{
+			get => base.TextAlignment;
+			set
+			{
+				if (base.TextAlignment != value)
+				{
+					base.TextAlignment = value;
+					UpdateHorizontalTextAlignment(value);
+				}
+			}
+		}
+
 		// Native Changed doesn't fire when the Text Property is set in code
 		// We use this event as a way to fire changes whenever the Text changes
 		// via code or user interaction.
@@ -66,7 +80,18 @@ public UIColor? PlaceholderTextColor
 			set => _placeholderLabel.TextColor = value;
 		}
 
-		public TextAlignment VerticalTextAlignment { get; set; }
+		public TextAlignment VerticalTextAlignment
+		{
+			get => _verticalTextAlignment;
+			set
+			{
+				if (_verticalTextAlignment != value)
+				{
+					_verticalTextAlignment = value;
+					ShouldCenterVertically();
+				}
+			}
+		}
 
 		public override string? Text
 		{
@@ -136,6 +161,14 @@ MauiLabel InitPlaceholderLabel()
 			return placeholderLabel;
 		}
 
+		void UpdateHorizontalTextAlignment(UITextAlignment textAlignment)
+		{
+			if (_placeholderLabel is null)
+				return;
+
+			_placeholderLabel.TextAlignment = textAlignment;
+		}
+
 		void UpdatePlaceholderLabelFrame()
 		{
 			if (Bounds != CGRect.Empty && _placeholderLabel is not null)
@@ -170,7 +203,7 @@ void ShouldCenterVertically()
 			{
 				Maui.TextAlignment.Center => new CGPoint(0, -Math.Max(1, availableSpace / 2)),
 				Maui.TextAlignment.End => new CGPoint(0, -Math.Max(1, availableSpace)),
-				_ => ContentOffset,
+				_ => default,
 			};
 
 			// Scroll the content to the cursor position if it is hidden by the keyboard

src/Core/src/Platform/iOS/TextViewExtensions.cs

@@ -128,6 +128,11 @@ public static void UpdateHorizontalTextAlignment(this UITextView textView, IEdit
 			textView.TextAlignment = editor.HorizontalTextAlignment.ToPlatformHorizontal(textView.EffectiveUserInterfaceLayoutDirection);
 		}
 
+		internal static void UpdateHorizontalTextAlignment(this MauiTextView textView, IEditor editor)
+		{
+			textView.TextAlignment = editor.HorizontalTextAlignment.ToPlatformHorizontal(textView.EffectiveUserInterfaceLayoutDirection);
+		}
+
 		public static void UpdateVerticalTextAlignment(this MauiTextView textView, IEditor editor)
 		{
 			textView.VerticalTextAlignment = editor.VerticalTextAlignment;

src/Core/src/PublicAPI/net-ios/PublicAPI.Unshipped.txt

@@ -1,2 +1,4 @@
 #nullable enable
 override Microsoft.Maui.Platform.MauiView.DidUpdateFocus(UIKit.UIFocusUpdateContext! context, UIKit.UIFocusAnimationCoordinator! coordinator) -> void
+override Microsoft.Maui.Platform.MauiTextView.TextAlignment.get -> UIKit.UITextAlignment
+override Microsoft.Maui.Platform.MauiTextView.TextAlignment.set -> void

src/Core/src/PublicAPI/net-maccatalyst/PublicAPI.Unshipped.txt

@@ -1,2 +1,4 @@
 #nullable enable
 override Microsoft.Maui.Platform.MauiView.DidUpdateFocus(UIKit.UIFocusUpdateContext! context, UIKit.UIFocusAnimationCoordinator! coordinator) -> void
+override Microsoft.Maui.Platform.MauiTextView.TextAlignment.get -> UIKit.UITextAlignment
+override Microsoft.Maui.Platform.MauiTextView.TextAlignment.set -> void