From 2ff2985a75b9e3e54a292c9dc4744eaa8d2b35d2 Mon Sep 17 00:00:00 2001
From: Jerome Laban <jerome.laban@nventive.com>
Date: Wed, 19 Jul 2023 09:35:59 -0400
Subject: [PATCH] fix(listview): [Android] Adjust datacontext for header/footer
 for ListView

---
 .../Given_ListViewBase.cs                     | 90 +++++++++++++++++++
 .../NativeListViewBaseAdapter.Android.cs      | 24 +++--
 2 files changed, 109 insertions(+), 5 deletions(-)

diff --git a/src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml_Controls/Given_ListViewBase.cs b/src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml_Controls/Given_ListViewBase.cs
index c54bacfb45c0..3b4d78c03273 100644
--- a/src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml_Controls/Given_ListViewBase.cs
+++ b/src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml_Controls/Given_ListViewBase.cs
@@ -2933,6 +2933,96 @@ private sealed class AlwaysEqualClass : IEquatable<AlwaysEqualClass>
 		[TestMethod]
 		public async Task When_Items_Are_Equal_But_Different_References_FlipView() => await When_Items_Are_Equal_But_Different_References_Common(new FlipView());
 
+		public record When_Header_DataContext_Model(string MyText);
+
+		[TestMethod]
+		[RunsOnUIThread]
+		public async Task When_Header_DataContext()
+		{
+			TextBlock header = new TextBlock { Text = "empty" };
+			TextBlock header2 = new TextBlock { Text = "empty" };
+
+			var SUT = new ListView()
+			{
+				ItemContainerStyle = BasicContainerStyle,
+				Header = new StackPanel
+				{
+					Background = new SolidColorBrush(Colors.Red),
+					Children = {
+						header,
+						header2,
+					}
+				}
+			};
+
+			header.SetBinding(TextBlock.TextProperty, new Binding { Path = new PropertyPath("MyText") });
+			header2.SetBinding(TextBlock.TextProperty, new Binding { Path = new PropertyPath(".") });
+
+			WindowHelper.WindowContent = SUT;
+			await WindowHelper.WaitForIdle();
+
+			var source = new[] {
+				new ListViewItem(){ Content = "item 1" },
+			};
+
+			SUT.ItemsSource = source;
+			await WindowHelper.WaitForIdle();
+
+			Assert.IsNull(header.DataContext);
+
+			SUT.DataContext = new When_Header_DataContext_Model("test value");
+			await WindowHelper.WaitForIdle();
+
+			Assert.AreEqual(SUT.DataContext, header.DataContext);
+			Assert.AreEqual("test value", header.Text);
+			Assert.AreEqual(SUT.DataContext, header2.DataContext);
+			Assert.AreEqual(header2.DataContext.ToString(), header2.Text);
+		}
+
+		[RunsOnUIThread]
+		[TestMethod]
+		public async Task When_Footer_DataContext()
+		{
+			TextBlock header = new TextBlock { Text = "empty" };
+			TextBlock header2 = new TextBlock { Text = "empty" };
+
+			var SUT = new ListView()
+			{
+				ItemContainerStyle = BasicContainerStyle,
+				Footer = new StackPanel
+				{
+					Background = new SolidColorBrush(Colors.Red),
+					Children = {
+						header,
+						header2,
+					}
+				}
+			};
+
+			header.SetBinding(TextBlock.TextProperty, new Binding { Path = new PropertyPath("MyText") });
+			header2.SetBinding(TextBlock.TextProperty, new Binding { Path = new PropertyPath(".") });
+
+			WindowHelper.WindowContent = SUT;
+			await WindowHelper.WaitForIdle();
+
+			var source = new[] {
+				new ListViewItem(){ Content = "item 1" },
+			};
+
+			SUT.ItemsSource = source;
+			await WindowHelper.WaitForIdle();
+
+			Assert.IsNull(header.DataContext);
+
+			SUT.DataContext = new When_Header_DataContext_Model("test value");
+			await WindowHelper.WaitForIdle();
+
+			Assert.AreEqual(SUT.DataContext, header.DataContext);
+			Assert.AreEqual("test value", header.Text);
+			Assert.AreEqual(SUT.DataContext, header2.DataContext);
+			Assert.AreEqual(header2.DataContext.ToString(), header2.Text);
+		}
+
 		private async Task When_Items_Are_Equal_But_Different_References_Common(Selector sut)
 		{
 			var obj1 = new AlwaysEqualClass();
diff --git a/src/Uno.UI/UI/Xaml/Controls/ListViewBase/NativeListViewBaseAdapter.Android.cs b/src/Uno.UI/UI/Xaml/Controls/ListViewBase/NativeListViewBaseAdapter.Android.cs
index 213a76c063f3..bd60f69c857b 100644
--- a/src/Uno.UI/UI/Xaml/Controls/ListViewBase/NativeListViewBaseAdapter.Android.cs
+++ b/src/Uno.UI/UI/Xaml/Controls/ListViewBase/NativeListViewBaseAdapter.Android.cs
@@ -75,7 +75,9 @@ public override void OnBindViewHolder(RecyclerView.ViewHolder holder, int positi
 			}
 
 			var isGroupHeader = parent.GetIsGroupHeader(position);
-			if (isGroupHeader || parent.GetIsHeader(position) || parent.GetIsFooter(position))
+			var isHeader = parent.GetIsHeader(position);
+			var isFooter = parent.GetIsFooter(position);
+			if (isGroupHeader || isHeader || isFooter)
 			{
 				var item = parent.GetElementFromDisplayPosition(position);
 
@@ -90,11 +92,23 @@ public override void OnBindViewHolder(RecyclerView.ViewHolder holder, int positi
 
 				var dataTemplate = GetDataTemplateFromItem(parent, item, viewType, isGroupHeader);
 
-				container.DataContext = item;
-				container.ContentTemplate = dataTemplate;
-				if (container.GetBindingExpression(ContentControl.ContentProperty) == null)
+
+				if (!isHeader && !isFooter)
+				{
+					container.DataContext = item;
+					container.ContentTemplate = dataTemplate;
+					if (container.GetBindingExpression(ContentControl.ContentProperty) == null)
+					{
+						container.SetBinding(ContentControl.ContentProperty, new Binding());
+					}
+				}
+				else
 				{
-					container.SetBinding(ContentControl.ContentProperty, new Binding());
+					// When showing the header/footer, the datacontext must be the listview's 
+					// datacontext. We only need to se the content of the container, not its
+					// datacontext.
+
+					container.Content = item;
 				}
 			}
 			else if (viewType == IsOwnContainerType)