Merge pull request AvaloniaUI#9699 from AvaloniaUI/fixes/7974-selecti…

…onmodel-eventargs-indexer Fix SelectionModelSelectionChangedEventArgs.SelectedItems indexer.
donandren · Feb 16, 2023 · 730e08d · 730e08d
1 parent f3acb6e
commit 730e08d
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Showing 2 changed files with 21 additions and 2 deletions.
diff --git a/src/Avalonia.Controls/Selection/SelectedItems.cs b/src/Avalonia.Controls/Selection/SelectedItems.cs
@@ -37,9 +37,9 @@ public SelectedItems(IReadOnlyList<IndexRange> ranges, ItemsSourceView<T>? items
                 {
                     return _owner.SelectedItem;
                 }
-                else if (Items is object)
+                else if (Items is not null && Ranges is not null)
                 {
-                    return Items[index];
+                    return Items[IndexRange.GetAt(Ranges, index)];
                 }
                 else
                 {

diff --git a/tests/Avalonia.Controls.UnitTests/Selection/SelectionModelTests_Single.cs b/tests/Avalonia.Controls.UnitTests/Selection/SelectionModelTests_Single.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Specialized;
+using System.Linq;
 using Avalonia.Collections;
 using Avalonia.Controls.Selection;
 using Avalonia.Controls.Utils;
@@ -1144,6 +1145,24 @@ public void Handles_Selection_Made_In_CollectionChanged()
                 Assert.Equal(new[] { "foo" }, target.SelectedItems);
                 Assert.Equal(0, target.AnchorIndex);
             }
+
+            [Fact]
+            public void SelectedItems_Indexer_Is_Correct()
+            {
+                // Issue #7974
+                var target = CreateTarget();
+                var raised = 0;
+
+                target.SelectionChanged += (s, e) =>
+                {
+                    Assert.Equal("bar", e.SelectedItems.First());
+                    Assert.Equal("bar", e.SelectedItems[0]);
+                    ++raised;
+                };
+
+                target.Select(1);
+                Assert.Equal(1, raised);
+            }
         }
 
         public class BatchUpdate