From 9cccb9f0c70bf539130f032240c6ebef9b2a3530 Mon Sep 17 00:00:00 2001
From: Steven Kirk <grokys@users.noreply.github.com>
Date: Fri, 29 Sep 2023 14:20:50 +0200
Subject: [PATCH] Unregister anchor candidates on unrealize.

Prevents the scroll jumping when a `TreeDataGrid` is removed and re-added to the visual tree.
---
 .../Primitives/TreeDataGridPresenterBase.cs                     | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Avalonia.Controls.TreeDataGrid/Primitives/TreeDataGridPresenterBase.cs b/src/Avalonia.Controls.TreeDataGrid/Primitives/TreeDataGridPresenterBase.cs
index 2ba5c22c..9e1f45dc 100644
--- a/src/Avalonia.Controls.TreeDataGrid/Primitives/TreeDataGridPresenterBase.cs
+++ b/src/Avalonia.Controls.TreeDataGrid/Primitives/TreeDataGridPresenterBase.cs
@@ -655,6 +655,7 @@ private void RecycleElement(Control element, int index)
                 UnrealizeElement(element);
                 element.IsVisible = false;
                 ElementFactory!.RecycleElement(element);
+                _scrollViewer?.UnregisterAnchorCandidate(element);
             }
         }
 
@@ -663,6 +664,7 @@ private void RecycleElementOnItemRemoved(Control element)
             UnrealizeElementOnItemRemoved(element);
             element.IsVisible = false;
             ElementFactory!.RecycleElement(element);
+            _scrollViewer?.UnregisterAnchorCandidate(element);
         }
 
         private void TrimUnrealizedChildren()