From 0f5285834dcdf97c8f5913f6044d3d6bc13e7c0f Mon Sep 17 00:00:00 2001
From: Damian Suess <djsuess@gmail.com>
Date: Wed, 31 May 2023 15:37:28 -0400
Subject: [PATCH] Converted ItemsControlRegionAdapter to use ItemsSource. As of
 Avalonia PR #10827, `ItemsControl.Items` is readonly and should use
 `ItemsControls.ItemsSource` (PR #10590)

---
 samples/SampleMvvmApp/Views/DashboardView.axaml            | 4 ++--
 src/Prism.Avalonia/Regions/ItemsControlRegionAdapter.cs    | 7 ++-----
 src/Prism.Avalonia/Regions/Region.cs                       | 1 +
 .../Mocks/Views/MockBindingsView.axaml                     | 2 +-
 4 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/samples/SampleMvvmApp/Views/DashboardView.axaml b/samples/SampleMvvmApp/Views/DashboardView.axaml
index 6abda6b..8bba943 100644
--- a/samples/SampleMvvmApp/Views/DashboardView.axaml
+++ b/samples/SampleMvvmApp/Views/DashboardView.axaml
@@ -30,7 +30,7 @@
 
       <ComboBox VerticalAlignment="Center"
                 HorizontalAlignment="Stretch"
-                Items="{Binding ThemeStyles}"
+                ItemsSource="{Binding ThemeStyles}"
                 SelectedItem="{Binding ThemeSelected}">
         <!--SelectedIndex="{Binding ThemeSelectedIndex}" >-->
         <ComboBox.ItemTemplate>
@@ -51,7 +51,7 @@
 
     <ListBox Grid.Row="3"
              Margin="2"
-             Items="{Binding ListItems}"
+             ItemsSource="{Binding ListItems}"
              ScrollViewer.HorizontalScrollBarVisibility="Visible"
              ScrollViewer.VerticalScrollBarVisibility="Visible"
              SelectedIndex="{Binding ListItemSelected}"
diff --git a/src/Prism.Avalonia/Regions/ItemsControlRegionAdapter.cs b/src/Prism.Avalonia/Regions/ItemsControlRegionAdapter.cs
index 34c59bb..b049cca 100644
--- a/src/Prism.Avalonia/Regions/ItemsControlRegionAdapter.cs
+++ b/src/Prism.Avalonia/Regions/ItemsControlRegionAdapter.cs
@@ -50,12 +50,9 @@ protected override void Adapt(IRegion region, ItemsControl regionTarget)
             }
 
             // Avalonia v11-Preview5 needs IRegion implement IList. Enforcing it to return AvaloniaList<object> fixes this.
-            // Avalonia v11-Preview8 ItemsControl.Items is readonly.
+            // Avalonia v11-Preview8 ItemsControl.Items is readonly (#10827).
             ////regionTarget.Items = region.Views as Avalonia.Collections.AvaloniaList<object>;
-            foreach (var item in region.Views as Avalonia.Collections.AvaloniaList<object>)
-            {
-                regionTarget.Items.Add(item);
-            }
+            regionTarget.ItemsSource = region.Views as Avalonia.Collections.AvaloniaList<object>;
         }
 
         /// <summary>
diff --git a/src/Prism.Avalonia/Regions/Region.cs b/src/Prism.Avalonia/Regions/Region.cs
index 2d1ebca..2fe7f7d 100644
--- a/src/Prism.Avalonia/Regions/Region.cs
+++ b/src/Prism.Avalonia/Regions/Region.cs
@@ -369,6 +369,7 @@ private void InnerAdd(object view, string viewName, IRegionManager scopedRegionM
                 {
                     throw new InvalidOperationException(String.Format(CultureInfo.InvariantCulture, Resources.RegionViewNameExistsException, viewName));
                 }
+
                 itemMetadata.Name = viewName;
             }
 
diff --git a/tests/Avalonia/Prism.Avalonia.Tests/Mocks/Views/MockBindingsView.axaml b/tests/Avalonia/Prism.Avalonia.Tests/Mocks/Views/MockBindingsView.axaml
index 9710317..e69769f 100644
--- a/tests/Avalonia/Prism.Avalonia.Tests/Mocks/Views/MockBindingsView.axaml
+++ b/tests/Avalonia/Prism.Avalonia.Tests/Mocks/Views/MockBindingsView.axaml
@@ -10,7 +10,7 @@
   <StackPanel>
     <ListBox Margin="2"
            VerticalAlignment="Bottom"
-           Items="{Binding ListItems}"
+           ItemsSource="{Binding ListItems}"
            ScrollViewer.HorizontalScrollBarVisibility="Visible"
            ScrollViewer.VerticalScrollBarVisibility="Visible"
            SelectedIndex="{Binding ListItemSelected}"