[iOS, Catalyst] Fixed CollectionView items height appears larger in Developer Balance sample

src/Controls/src/Core/Handlers/Items2/ItemsViewHandler2.iOS.cs

@@ -186,14 +186,7 @@ protected bool IsIndexPathValid(NSIndexPath indexPath)
 		public override Size GetDesiredSize(double widthConstraint, double heightConstraint)
 		{
 			var contentSize = Controller.GetSize();
-
-			// If contentSize comes back null, it means none of the content has been realized yet;
-			// we need to return the expansive size the collection view wants by default to get
-			// it to start measuring its content
-			if (contentSize.Height == 0 || contentSize.Width == 0)
-			{
-				return base.GetDesiredSize(widthConstraint, heightConstraint);
-			}
+			contentSize = EnsureContentSizeForScrollDirection(widthConstraint, heightConstraint, contentSize);
 
 			// Our target size is the smaller of it and the constraints
 			var width = contentSize.Width <= widthConstraint ? contentSize.Width : widthConstraint;
@@ -206,5 +199,30 @@ public override Size GetDesiredSize(double widthConstraint, double heightConstra
 
 			return new Size(width, height);
 		}
+
+		Size EnsureContentSizeForScrollDirection(double widthConstraint, double heightConstraint, Size contentSize)
+		{
+			// Get the CollectionView orientation
+			var scrollDirection = Controller.GetScrollDirection();
+
+			// If contentSize is zero in the relevant dimension (height for vertical, width for horizontal),
+			// it means none of the content has been realized yet; we need to return the expansive size
+			// the collection view wants by default to get it to start measuring its content
+			if ((scrollDirection == UICollectionViewScrollDirection.Vertical && contentSize.Height == 0) ||
+				(scrollDirection == UICollectionViewScrollDirection.Horizontal && contentSize.Width == 0))
+			{
+				var desiredSize = base.GetDesiredSize(widthConstraint, heightConstraint);
+				if (scrollDirection == UICollectionViewScrollDirection.Vertical)
+				{
+					contentSize.Height = desiredSize.Height;
+				}
+				else
+				{
+					contentSize.Width = desiredSize.Width;
+				}
+			}
+
+			return contentSize;
+		}
 	}
 }

src/Controls/src/Core/Handlers/Items2/iOS/ItemsViewController2.cs

@@ -449,6 +449,11 @@ internal Size GetSize()
 			return CollectionView.CollectionViewLayout.CollectionViewContentSize.ToSize();
 		}
 
+		internal UICollectionViewScrollDirection GetScrollDirection()
+		{
+			return ScrollDirection;
+		}
+
 		internal void UpdateView(object view, DataTemplate viewTemplate, ref UIView uiView, ref VisualElement formsElement)
 		{
 			// Is view set on the ItemsView?

src/Controls/tests/TestCases.HostApp/Issues/Issue31897.cs

@@ -0,0 +1,176 @@
+using System.ComponentModel;
+
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 31897, "CollectionView card height appears larger in Developer Balance sample", PlatformAffected.iOS | PlatformAffected.macOS)]
+public class Issue31897 : ContentPage
+{
+	Button getHeight;
+	Label HeightLabel;
+	CollectionView2 ProjectsCollectionView;
+
+	public Issue31897()
+	{
+		var mainGrid = new Grid();
+
+		var scrollView = new ScrollView();
+
+		// Create the inner grid with padding and row spacing
+		var innerGrid = new Grid
+		{
+			Padding = new Thickness(10),
+			RowSpacing = 10
+		};
+
+		// Add row definitions
+		innerGrid.RowDefinitions.Add(new RowDefinition { Height = GridLength.Auto });
+		innerGrid.RowDefinitions.Add(new RowDefinition { Height = GridLength.Auto });
+		innerGrid.RowDefinitions.Add(new RowDefinition { Height = GridLength.Auto });
+
+		// Create the "Get CV Height" button
+		getHeight = new Button
+		{
+			Text = "Get CV Height",
+			AutomationId = "GetHeightButton"
+		};
+
+		getHeight.Clicked += (object sender, EventArgs e) =>
+		{
+			HeightLabel.Text = Math.Round(ProjectsCollectionView.Height).ToString();
+		};
+
+		getHeight.SetValue(SemanticProperties.HeadingLevelProperty, SemanticHeadingLevel.Level1);
+		Grid.SetRow(getHeight, 0);
+
+		// Create the height label
+		HeightLabel = new Label();
+		HeightLabel.AutomationId = "HeightLabel";
+		HeightLabel.SetValue(SemanticProperties.HeadingLevelProperty, SemanticHeadingLevel.Level1);
+		Grid.SetRow(HeightLabel, 1);
+
+		// Create the CollectionView
+		ProjectsCollectionView = new CollectionView2
+		{
+			Margin = new Thickness(-7.5, 0),
+			MinimumHeightRequest = 250,
+			SelectionMode = SelectionMode.Single
+		};
+
+		// Set up the ItemsLayout
+		ProjectsCollectionView.ItemsLayout = new LinearItemsLayout(ItemsLayoutOrientation.Horizontal)
+		{
+			ItemSpacing = 7.5
+		};
+
+		// Create the DataTemplate for items
+		var itemTemplate = new DataTemplate(() =>
+		{
+			var border = new Border
+			{
+				WidthRequest = 200,
+				Background = Colors.GreenYellow
+			};
+
+			var contentView = new ContentView();
+
+			var verticalStackLayout = new VerticalStackLayout
+			{
+				Spacing = 15,
+				Background = Colors.Red,
+				VerticalOptions = LayoutOptions.Start
+			};
+
+			// Name label
+			var nameLabel = new Label
+			{
+				TextColor = Colors.Gray,
+				FontSize = 14,
+				TextTransform = TextTransform.Uppercase
+			};
+			nameLabel.SetBinding(Label.TextProperty, "Name");
+
+			// Description label
+			var descriptionLabel = new Label
+			{
+				LineBreakMode = LineBreakMode.WordWrap
+			};
+			descriptionLabel.SetBinding(Label.TextProperty, "Description");
+
+			verticalStackLayout.Children.Add(nameLabel);
+			verticalStackLayout.Children.Add(descriptionLabel);
+			contentView.Content = verticalStackLayout;
+			border.Content = contentView;
+
+			return border;
+		});
+
+		ProjectsCollectionView.ItemTemplate = itemTemplate;
+
+		// Set up data binding
+		var viewModel = new Issue31897ViewModel();
+		BindingContext = viewModel;
+		ProjectsCollectionView.SetBinding(CollectionView.ItemsSourceProperty, "Projects");
+
+		Grid.SetRow(ProjectsCollectionView, 2);
+
+		// Add all controls to the inner grid
+		innerGrid.Children.Add(getHeight);
+		innerGrid.Children.Add(HeightLabel);
+		innerGrid.Children.Add(ProjectsCollectionView);
+
+		// Set up the hierarchy
+		scrollView.Content = innerGrid;
+		mainGrid.Children.Add(scrollView);
+		Content = mainGrid;
+	}
+
+	public class Issue31897ViewModel : INotifyPropertyChanged
+	{
+		List<Issue31897Project> _projects = new();
+
+		public event PropertyChangedEventHandler PropertyChanged;
+
+		protected virtual void OnPropertyChanged(string propertyName)
+		{
+			PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+		}
+
+		public List<Issue31897Project> Projects
+		{
+			get { return _projects; }
+			set
+			{
+				_projects = value;
+				OnPropertyChanged(nameof(Projects));
+			}
+		}
+
+		public Issue31897ViewModel()
+		{
+			LoadData();
+		}
+
+		void LoadData()
+		{
+			var projects = new List<Issue31897Project>();
+			for (int i = 0; i < 4; i++)
+			{
+				projects.Add(new Issue31897Project
+				{
+					ID = i,
+					Name = "Developer balance card view " + (i + 1),
+					Description = "This is a sample description for project " + (i + 1)
+				});
+			}
+
+			Projects = projects;
+		}
+	}
+
+	public class Issue31897Project
+	{
+		public int ID { get; set; }
+		public string Name { get; set; } = string.Empty;
+		public string Description { get; set; } = string.Empty;
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue31897.cs

@@ -0,0 +1,23 @@
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue31897 : _IssuesUITest
+{
+	public Issue31897(TestDevice testDevice) : base(testDevice)
+	{
+	}
+	public override string Issue => "CollectionView card height appears larger in Developer Balance sample";
+
+	[Test]
+	[Category(UITestCategories.CollectionView)]
+	public void EnsureCollectionViewLayoutOnItemsSourceChange()
+	{
+		App.WaitForElement("GetHeightButton");
+		App.Tap("GetHeightButton");
+		var label = App.WaitForElement("HeightLabel");
+		Assert.That(label.GetText(), Is.EqualTo("250"));
+	}
+}