Include headers/footers in EmptySource count so they show up when Ite…

…msSource is null Fixes #8934
dotnet · Jul 3, 2023 · 6022c81 · 6022c81
1 parent 752c724
commit 6022c81
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Showing 3 changed files with 48 additions and 9 deletions.
diff --git a/src/Controls/src/Core/Handlers/Items/Android/Adapters/EmptyViewAdapter.cs b/src/Controls/src/Core/Handlers/Items/Android/Adapters/EmptyViewAdapter.cs
@@ -10,12 +10,12 @@ namespace Microsoft.Maui.Controls.Handlers.Items
 {
 	public class EmptyViewAdapter : RecyclerView.Adapter
 	{
-		int _headerHeight;
+		double _headerHeight;
 		int _headerViewType;
 		object _headerView;
 		DataTemplate _headerViewTemplate;
 
-		int _footerHeight;
+		double _footerHeight;
 		int _footerViewType;
 		object _footerView;
 		DataTemplate _footerViewTemplate;
@@ -301,18 +301,25 @@ void UpdateHeaderFooterHeight(object item, bool isHeader)
 			if (item == null)
 				return;
 
-			var sizeRequest = new SizeRequest(new Size(0, 0));
+			var size = Size.Zero;
 
-			if (item is View view)
-				sizeRequest = view.Measure(double.PositiveInfinity, double.PositiveInfinity, MeasureFlags.IncludeMargins);
+			if (item is IView view)
+			{
+				if (view.Handler == null)
+				{
+					TemplateHelpers.GetHandler(view as View, ItemsView.FindMauiContext());
+				}
+
+				size = view.Measure(double.PositiveInfinity, double.PositiveInfinity);
+			}
 
 			if (item is DataTemplate dataTemplate)
 			{
-				var content = dataTemplate.CreateContent() as View;
-				sizeRequest = content.Measure(double.PositiveInfinity, double.PositiveInfinity, MeasureFlags.IncludeMargins);
+				var content = dataTemplate.CreateContent() as IView;
+				size = content.Measure(double.PositiveInfinity, double.PositiveInfinity);
 			}
 
-			var itemHeight = (int)sizeRequest.Request.Height;
+			var itemHeight = size.Height;
 
 			if (isHeader)
 				_headerHeight = itemHeight;

diff --git a/src/Controls/src/Core/Handlers/Items/Android/ItemsSources/EmptySource.cs b/src/Controls/src/Core/Handlers/Items/Android/ItemsSources/EmptySource.cs
@@ -3,7 +3,7 @@ namespace Microsoft.Maui.Controls.Handlers.Items
 {
 	sealed internal class EmptySource : IItemsViewSource
 	{
-		public int Count => 0;
+		public int Count => (HasHeader? 1 : 0) + (HasFooter? 1 : 0);
 
 		public bool HasHeader { get; set; }
 		public bool HasFooter { get; set; }

diff --git a/src/Controls/tests/DeviceTests/Elements/CollectionView/CollectionViewTests.Android.cs b/src/Controls/tests/DeviceTests/Elements/CollectionView/CollectionViewTests.Android.cs
@@ -50,5 +50,37 @@ await CreateHandlerAndAddToWindow<IWindowHandler>(rootPage,
 			// Without Exceptions here, the test has passed.
 			Assert.Equal(0, (rootPage as IPageContainer<Page>).CurrentPage.Navigation.ModalStack.Count);
 		}
+
+		[Fact]
+		public async Task NullItemsSourceDisplaysHeaderFooterAndEmptyView() 
+		{
+			SetupBuilder();
+
+			var emptyView = new Label { Text = "Empty" };
+			var header = new Label { Text = "Header" };
+			var footer = new Label { Text = "Footer" };
+
+			var collectionView = new CollectionView
+			{
+				ItemsSource = null,
+				EmptyView = emptyView,
+				Header = header,
+				Footer = footer
+			};
+
+			ContentPage contentPage = new ContentPage() { Content = collectionView };
+
+			var frame = collectionView.Frame;
+
+			await CreateHandlerAndAddToWindow<IWindowHandler>(contentPage,
+				async (_) =>
+				{
+					await WaitForUIUpdate(frame, collectionView);
+
+					Assert.True(emptyView.Height > 0, "EmptyView is not displayed");
+					Assert.True(header.Height > 0, "Header is not displayed");
+					Assert.True(footer.Height > 0, "Footer is not displayed");
+				});
+		}
 	}
 }