[Windows] Fix CollectionView broken test

src/Controls/samples/Controls.Sample/Pages/Controls/CollectionViewGalleries/SpacingGalleries/DefaultItemSpacing.xaml

@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ContentPage 
+    xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+    x:Class="Maui.Controls.Sample.Pages.CollectionViewGalleries.SpacingGalleries.DefaultItemSpacing"
+    Title="Default ItemSpacing">
+    <Grid
+        RowDefinitions="Auto, *"
+        Padding="12">
+        <Label 
+            Text="By default, there is no space between each item in a CollectionView."/>
+        <CollectionView 
+            Grid.Row="1"
+            ItemsLayout="VerticalList"
+            ItemsSource="{Binding Items}"
+            BackgroundColor="Red">
+            <CollectionView.ItemTemplate>
+                <DataTemplate >
+                    <Label 
+                        Text="{Binding .}"
+                        TextColor="Black"
+                        FontSize="14"
+                        BackgroundColor="Yellow"/>
+                </DataTemplate>
+            </CollectionView.ItemTemplate>
+        </CollectionView>
+    </Grid>
+</ContentPage>

src/Controls/samples/Controls.Sample/Pages/Controls/CollectionViewGalleries/SpacingGalleries/DefaultItemSpacing.xaml.cs

@@ -0,0 +1,26 @@
+using System.Collections.Generic;
+using Microsoft.Maui.Controls;
+
+namespace Maui.Controls.Sample.Pages.CollectionViewGalleries.SpacingGalleries
+{
+	public partial class DefaultItemSpacing : ContentPage
+	{
+		public DefaultItemSpacing()
+		{
+			InitializeComponent();
+			Items = new();
+			AddItems();
+			BindingContext = this;
+		}
+
+		public List<string> Items { get; set; }
+
+		void AddItems()
+		{
+			for (var i = 0; i < 10; i++)
+			{
+				Items.Add($"Item {i + 1}");
+			}
+		}
+	}
+}

src/Controls/samples/Controls.Sample/Pages/Controls/CollectionViewGalleries/SpacingGalleries/ItemsSpacingGallery.cs

@@ -18,7 +18,9 @@ public ItemsSpacingGallery()
 				{
 					Children =
 					{
-						descriptionLabel,
+						descriptionLabel,   
+						GalleryBuilder.NavButton("Default Spacing", () =>
+							new DefaultItemSpacing (), Navigation),
 						GalleryBuilder.NavButton("Vertical List Spacing", () =>
 							new SpacingGallery (LinearItemsLayout.Vertical), Navigation),
 						GalleryBuilder.NavButton("Horizontal List Spacing", () =>

src/Controls/src/Core/Platform/Windows/Extensions/CollectionViewExtensions.cs

@@ -13,13 +13,20 @@ public static class CollectionViewExtensions
 			if (layout is null)
 				return null;
 
-			var h = layout?.ItemSpacing ?? 0;
-			var v = layout?.ItemSpacing ?? 0;
-			var margin = WinUIHelpers.CreateThickness(h, v, h, v);
-
 			var style = new WStyle(typeof(GridViewItem));
 
-			style.Setters.Add(new WSetter(FrameworkElement.MarginProperty, margin));
+			if (layout?.Orientation == ItemsLayoutOrientation.Vertical)
+			{
+				style.Setters.Add(new WSetter(FrameworkElement.MinHeightProperty, 0));
+
+				var h = layout?.ItemSpacing ?? 0;
+				var v = layout?.ItemSpacing ?? 0;
+				var margin = WinUIHelpers.CreateThickness(h, v, h, v);
+				style.Setters.Add(new WSetter(FrameworkElement.MarginProperty, margin));
+			}
+			else
+				style.Setters.Add(new WSetter(FrameworkElement.MinWidthProperty, 0));
+
 			style.Setters.Add(new WSetter(Control.PaddingProperty, WinUIHelpers.CreateThickness(0)));
 			style.Setters.Add(new WSetter(Control.HorizontalContentAlignmentProperty, HorizontalAlignment.Stretch));
 
@@ -31,13 +38,18 @@ public static class CollectionViewExtensions
 			if (layout is null)
 				return null;
 
+			var style = new WStyle(typeof(GridViewItem));
+
+			if (layout?.Orientation == ItemsLayoutOrientation.Vertical)
+				style.Setters.Add(new WSetter(FrameworkElement.MinHeightProperty, 0));
+			else
+				style.Setters.Add(new WSetter(FrameworkElement.MinWidthProperty, 0));
+
 			var h = layout?.HorizontalItemSpacing ?? 0;
 			var v = layout?.VerticalItemSpacing ?? 0;
 			var margin = WinUIHelpers.CreateThickness(h, v, h, v);
-
-			var style = new WStyle(typeof(GridViewItem));
-
 			style.Setters.Add(new WSetter(FrameworkElement.MarginProperty, margin));
+
 			style.Setters.Add(new WSetter(Control.PaddingProperty, WinUIHelpers.CreateThickness(0)));
 			style.Setters.Add(new WSetter(Control.HorizontalContentAlignmentProperty, HorizontalAlignment.Stretch));
 

src/Controls/tests/DeviceTests/Elements/CollectionView/CollectionViewTests.Windows.cs

@@ -54,7 +54,7 @@ await CreateHandlerAndAddToWindow<LayoutHandler>(layout, (handler) =>
 			});
 		}
 
-		[Fact(Skip = "FIX FOR .NET8")]
+		[Fact]
 		public async Task ValidateItemContainerDefaultHeight()
 		{
 			SetupBuilder();