Implement HorizontalTextAlignment property in WinUI Picker

eng/package.ps1

@@ -3,6 +3,8 @@ param(
   [string] $msbuild = "${env:ProgramFiles(x86)}\Microsoft Visual Studio\2019\Enterprise\MSBuild\Current\Bin\MSBuild.exe"
 )
 
+$ErrorActionPreference = "Stop"
+
 $artifacts = Join-Path $PSScriptRoot ../artifacts
 $sln = Join-Path $PSScriptRoot ../Microsoft.Maui-net6.sln
 
@@ -58,13 +60,15 @@ if ($IsWindows)
             /t:build `
             /p:Packing=true `
             /bl:"$artifacts/maui-build-$configuration.binlog"
+        if (!$?) { throw "Build failed." }
 
         & $msbuild $sln `
             /p:configuration=$configuration `
             /p:SymbolPackageFormat=snupkg `
             /t:pack `
             /p:Packing=true `
             /bl:"$artifacts/maui-pack-$configuration.binlog"
+        if (!$?) { throw "Build failed." }
     }
     finally
     {
@@ -86,4 +90,5 @@ else
         -c:$configuration `
         -p:SymbolPackageFormat=snupkg `
         -bl:$artifacts/maui-pack-$configuration.binlog
+    if (!$?) { throw "Build failed." }
 }

src/Compatibility/Core/src/WinUI/AlignmentExtensions.cs

@@ -37,6 +37,7 @@ internal static VerticalAlignment ToNativeVerticalAlignment(this TextAlignment a
 			}
 		}
 
+		[PortHandler]
 		internal static HorizontalAlignment ToNativeHorizontalAlignment(this TextAlignment alignment)
 		{
 			switch (alignment)

src/Compatibility/Core/src/WinUI/PickerRenderer.cs

@@ -235,10 +235,12 @@ void UpdateTitle()
 			Control.DataContext = Element;
 		}
 
+		[PortHandler]
 		void UpdateHorizontalTextAlignment()
 		{
 			Control.HorizontalContentAlignment = Element.HorizontalTextAlignment.ToNativeHorizontalAlignment();
 		}
+
 		void UpdateVerticalTextAlignment()
 		{
 			Control.VerticalContentAlignment = Element.VerticalTextAlignment.ToNativeVerticalAlignment();

src/Core/src/Handlers/Picker/PickerHandler.Windows.cs

@@ -62,8 +62,10 @@ public static void MapTextColor(PickerHandler handler, IPicker picker)
 			handler.NativeView?.UpdateTextColor(picker, handler._defaultForeground);
 		}
 
-		[MissingMapper]
-		public static void MapHorizontalTextAlignment(PickerHandler handler, IPicker view) { }
+		public static void MapHorizontalTextAlignment(PickerHandler handler, IPicker picker)
+		{
+			handler.NativeView?.UpdateHorizontalTextAlignment(picker);
+		}
 
 		void OnControlSelectionChanged(object? sender, WSelectionChangedEventArgs e)
 		{

src/Core/src/Platform/Windows/AlignmentExtensions.cs

@@ -0,0 +1,20 @@
+using Microsoft.UI.Xaml;
+
+namespace Microsoft.Maui
+{
+	public static class AlignmentExtensions
+	{
+		public static HorizontalAlignment ToNativeHorizontalAlignment(this TextAlignment alignment)
+		{
+			switch (alignment)
+			{
+				case TextAlignment.Center:
+					return HorizontalAlignment.Center;
+				case TextAlignment.End:
+					return HorizontalAlignment.Right;
+				default:
+					return HorizontalAlignment.Left;
+			}
+		}
+	}
+}

src/Core/src/Platform/Windows/PickerExtensions.cs

@@ -1,6 +1,5 @@
 #nullable enable
 using Microsoft.Maui.Graphics;
-using Microsoft.UI.Xaml.Controls;
 using WBrush = Microsoft.UI.Xaml.Media.Brush;
 
 namespace Microsoft.Maui
@@ -41,6 +40,11 @@ public static void UpdateCharacterSpacing(this MauiComboBox nativeComboBox, IPic
 		}
 
 		public static void UpdateFont(this MauiComboBox nativeComboBox, IPicker picker, IFontManager fontManager) =>
-			nativeComboBox.UpdateFont(picker.Font, fontManager);
+			nativeComboBox.UpdateFont(picker.Font, fontManager); 
+
+		public static void UpdateHorizontalTextAlignment(this MauiComboBox nativeComboBox, IPicker picker)
+		{
+			nativeComboBox.HorizontalContentAlignment = picker.HorizontalTextAlignment.ToNativeHorizontalAlignment();
+		}
 	}
 }