Container cleanups.

Wino.Mail.WinUI/Controls/ListView/WinoListView.cs

@@ -1,4 +1,5 @@
-using Microsoft.UI.Xaml;
+using System.Diagnostics;
+using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
 using Wino.Mail.ViewModels.Data;
 
@@ -8,26 +9,6 @@ public partial class WinoListView : Microsoft.UI.Xaml.Controls.ListView
 {
     public bool IsAllSelected => Items.Count == SelectedItems.Count;
 
-    public WinoListView()
-    {
-        ChoosingItemContainer += WinoListView_ChoosingItemContainer;
-    }
-
-    private void WinoListView_ChoosingItemContainer(ListViewBase sender, ChoosingItemContainerEventArgs args)
-    {
-        if (args.Item is ThreadMailItemViewModel)
-        {
-            args.ItemContainer = new WinoThreadMailItemViewModelListViewItem();
-        }
-        else if (args.Item is MailItemViewModel)
-        {
-            args.ItemContainer = new WinoMailItemViewModelListViewItem();
-        }
-
-        // Handle the preparation in PrepareContainerForItemOverride
-        args.IsContainerPrepared = false;
-    }
-
     protected override void PrepareContainerForItemOverride(DependencyObject element, object item)
     {
         if (item is MailItemViewModel mailItemViewModel && element is WinoMailItemViewModelListViewItem container)
@@ -45,6 +26,19 @@ public partial class WinoListView : Microsoft.UI.Xaml.Controls.ListView
         base.PrepareContainerForItemOverride(element, item);
     }
 
+    protected override void ClearContainerForItemOverride(DependencyObject element, object item)
+    {
+        if (item is IMailListItem mailListItem)
+        {
+            if (element is WinoThreadMailItemViewModelListViewItem threadMailItemViewModelListViewItem) threadMailItemViewModelListViewItem.Cleanup();
+            if (element is WinoMailItemViewModelListViewItem winoMailItemViewModelListViewItem) winoMailItemViewModelListViewItem.Cleanup();
+        }
+
+        base.ClearContainerForItemOverride(element, item);
+
+        Debug.WriteLine($"Cleaned container");
+    }
+
     public bool SelectMailItemContainer(MailItemViewModel mailItemViewModel)
     {
         WinoMailItemViewModelListViewItem? itemContainer = null;

Wino.Mail.WinUI/Controls/ListView/WinoMailItemViewModelListViewItem.cs

@@ -8,11 +8,12 @@ namespace Wino.Mail.WinUI.Controls.ListView;
 
 public partial class WinoMailItemViewModelListViewItem : ListViewItem
 {
+    private readonly long _selectionChangeCallbackToken;
     public WinoMailItemViewModelListViewItem()
     {
         DefaultStyleKey = typeof(WinoMailItemViewModelListViewItem);
 
-        RegisterPropertyChangedCallback(IsSelectedProperty, OnIsSelectedChanged);
+        _selectionChangeCallbackToken = RegisterPropertyChangedCallback(IsSelectedProperty, OnIsSelectedChanged);
     }
 
     protected override void OnContentChanged(object oldContent, object newContent)
@@ -31,6 +32,16 @@ public partial class WinoMailItemViewModelListViewItem : ListViewItem
         }
     }
 
+    public void Cleanup()
+    {
+        if (Content is MailItemViewModel mailItem)
+        {
+            UnregisterSelectionCallback(mailItem);
+
+            UnregisterPropertyChangedCallback(IsSelectedProperty, _selectionChangeCallbackToken);
+        }
+    }
+
     private void UnregisterSelectionCallback(IMailListItem mailItem)
     {
         mailItem.PropertyChanged -= MailPropChanged;

Wino.Mail.WinUI/Controls/ListView/WinoThreadMailItemViewModelListViewItem.cs

@@ -18,9 +18,22 @@ public partial class WinoThreadMailItemViewModelListViewItem : ListViewItem
 
     public static readonly DependencyProperty IsThreadExpandedProperty = DependencyProperty.Register(nameof(IsThreadExpanded), typeof(bool), typeof(WinoThreadMailItemViewModelListViewItem), new PropertyMetadata(false, new PropertyChangedCallback(OnIsThreadExpandedChanged)));
 
+    private readonly long _selectionChangeCallbackToken;
     public WinoThreadMailItemViewModelListViewItem()
     {
-        RegisterPropertyChangedCallback(IsSelectedProperty, OnIsSelectedChanged);
+        DefaultStyleKey = typeof(WinoThreadMailItemViewModelListViewItem);
+
+        _selectionChangeCallbackToken = RegisterPropertyChangedCallback(IsSelectedProperty, OnIsSelectedChanged);
+    }
+
+    public void Cleanup()
+    {
+        if (Content is ThreadMailItemViewModel mailItem)
+        {
+            UnregisterSelectionCallback(mailItem);
+
+            UnregisterPropertyChangedCallback(IsSelectedProperty, _selectionChangeCallbackToken);
+        }
     }
 
     private static void OnIsThreadExpandedChanged(DependencyObject sender, DependencyPropertyChangedEventArgs dp)
@@ -70,7 +83,7 @@ public partial class WinoThreadMailItemViewModelListViewItem : ListViewItem
         IsThreadExpanded = IsSelected;
     }
 
-    private void UnregisterSelectionCallback(ThreadMailItemViewModel mailItem)
+    public void UnregisterSelectionCallback(ThreadMailItemViewModel mailItem)
     {
         mailItem.PropertyChanged -= MailPropChanged;
     }