From d26d9842566601065ae6c75d982a4ecafb76494a Mon Sep 17 00:00:00 2001
From: Andrey Kunchev <donandren@gmail.com>
Date: Tue, 20 Nov 2018 00:58:23 +0200
Subject: [PATCH] focus dropdown item in more safe manner

---
 src/Avalonia.Controls/DropDown.cs | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/src/Avalonia.Controls/DropDown.cs b/src/Avalonia.Controls/DropDown.cs
index 847db8a089..4ac2b6f822 100644
--- a/src/Avalonia.Controls/DropDown.cs
+++ b/src/Avalonia.Controls/DropDown.cs
@@ -170,6 +170,7 @@ namespace Avalonia.Controls
                     e.Handled = true;
                 }
             }
+
             base.OnPointerPressed(e);
         }
 
@@ -199,18 +200,26 @@ namespace Avalonia.Controls
 
         private void PopupOpened(object sender, EventArgs e)
         {
-            var selectedIndex = SelectedIndex;
-
-            if (selectedIndex != -1)
-            {
-                var container = ItemContainerGenerator.ContainerFromIndex(selectedIndex);
-                container?.Focus();
-            }
+            TryFocusSelectedItem();
         }
 
         private void SelectedItemChanged(AvaloniaPropertyChangedEventArgs e)
         {
             UpdateSelectionBoxItem(e.NewValue);
+            TryFocusSelectedItem();
+        }
+
+        private void TryFocusSelectedItem()
+        {
+            var selectedIndex = SelectedIndex;
+            if (IsDropDownOpen && selectedIndex != -1)
+            {
+                var container = ItemContainerGenerator.ContainerFromIndex(selectedIndex);
+                if (container != null && container.Focusable)
+                {
+                    container.Focus();
+                }
+            }
         }
 
         private void UpdateSelectionBoxItem(object item)