Removed the INC registrations for list view items.

Wino.Mail.ViewModels/Data/MailItemViewModel.cs

@@ -42,6 +42,15 @@ public partial class MailItemViewModel(MailCopy mailCopy) : ObservableRecipient,
     [NotifyPropertyChangedRecipients]
     public partial bool IsSelected { get; set; }
 
+    /// <summary>
+    /// Direct callback invoked when <see cref="IsSelected"/> changes.
+    /// Used by the ListViewItem container to update its IsCustomSelected DP
+    /// without subscribing to INotifyPropertyChanged (faster, AOT-safe).
+    /// </summary>
+    public Action<bool> OnSelectionChanged { get; set; }
+
+    partial void OnIsSelectedChanged(bool value) => OnSelectionChanged?.Invoke(value);
+
     /// <summary>
     /// Indicates if this mail item is currently being processed by a network operation.
     /// Used to show loading state in the UI.

Wino.Mail.ViewModels/Data/ThreadMailItemViewModel.cs

@@ -14,6 +14,8 @@ namespace Wino.Mail.ViewModels.Data;
 public partial class ThreadMailItemViewModel : ObservableRecipient, IMailListItem
 {
     private readonly string _threadId;
+    private readonly HashSet<Guid> _uniqueIdSet = [];
+    private MailItemViewModel _cachedLatestMailViewModel;
 
     [ObservableProperty]
     [NotifyPropertyChangedRecipients]
@@ -25,6 +27,15 @@ public partial class ThreadMailItemViewModel : ObservableRecipient, IMailListIte
     [NotifyPropertyChangedFor(nameof(IsSelectedOrExpanded))]
     public partial bool IsSelected { get; set; }
 
+    /// <summary>
+    /// Direct callback invoked when <see cref="IsSelected"/> changes.
+    /// Used by the ListViewItem container to update its IsCustomSelected DP
+    /// without subscribing to INotifyPropertyChanged (faster, AOT-safe).
+    /// </summary>
+    public Action<bool> OnSelectionChanged { get; set; }
+
+    partial void OnIsSelectedChanged(bool value) => OnSelectionChanged?.Invoke(value);
+
     [ObservableProperty]
     public partial bool IsBusy { get; set; }
 
@@ -168,7 +179,7 @@ public partial class ThreadMailItemViewModel : ObservableRecipient, IMailListIte
     [NotifyPropertyChangedFor(nameof(Base64ContactPicture))]
     public partial ObservableCollection<MailItemViewModel> ThreadEmails { get; set; } = [];
 
-    private MailItemViewModel latestMailViewModel => ThreadEmails.OrderByDescending(e => e.MailCopy?.CreationDate).FirstOrDefault()!;
+    private MailItemViewModel latestMailViewModel => _cachedLatestMailViewModel;
 
     public DateTime SortingDate => CreationDate;
 
@@ -200,6 +211,8 @@ public partial class ThreadMailItemViewModel : ObservableRecipient, IMailListIte
         }
 
         ThreadEmails.Insert(insertIndex, email);
+        _uniqueIdSet.Add(email.MailCopy.UniqueId);
+        _cachedLatestMailViewModel = ThreadEmails[0];
         // Reassign to trigger property change notifications
         ThreadEmails = ThreadEmails;
     }
@@ -211,6 +224,8 @@ public partial class ThreadMailItemViewModel : ObservableRecipient, IMailListIte
     {
         if (ThreadEmails.Remove(email))
         {
+            _uniqueIdSet.Remove(email.MailCopy.UniqueId);
+            _cachedLatestMailViewModel = ThreadEmails.Count > 0 ? ThreadEmails[0] : null;
             // Reassign to trigger property change notifications
             ThreadEmails = ThreadEmails;
         }
@@ -253,7 +268,7 @@ public partial class ThreadMailItemViewModel : ObservableRecipient, IMailListIte
     /// <summary>
     /// Checks if this thread contains an email with the specified unique ID
     /// </summary>
-    public bool HasUniqueId(Guid uniqueId) => ThreadEmails.Any(email => email.MailCopy.UniqueId == uniqueId);
+    public bool HasUniqueId(Guid uniqueId) => _uniqueIdSet.Contains(uniqueId);
 
     public IEnumerable<Guid> GetContainingIds() => ThreadEmails.Select(a => a.MailCopy.UniqueId);
 

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

@@ -69,14 +69,12 @@ public partial class WinoListView : Microsoft.UI.Xaml.Controls.ListView
             && container.Item != mailItemViewModel)
         {
             container.Item = mailItemViewModel;
-            container.IsCustomSelected = mailItemViewModel.IsSelected;
         }
         else if (item is ThreadMailItemViewModel threadMailItemViewModel
             && element is WinoThreadMailItemViewModelListViewItem threadContainer
             && threadContainer.Item != threadMailItemViewModel)
         {
             threadContainer.Item = threadMailItemViewModel;
-            threadContainer.IsSelected = threadMailItemViewModel.IsSelected;
             threadContainer.IsThreadExpanded = threadMailItemViewModel.IsThreadExpanded;
         }
     }
@@ -88,12 +86,10 @@ public partial class WinoListView : Microsoft.UI.Xaml.Controls.ListView
         if (item is MailItemViewModel mailItemViewModel && element is WinoMailItemViewModelListViewItem container)
         {
             container.Item = null;
-            container.IsCustomSelected = false;
         }
         else if (item is ThreadMailItemViewModel threadMailItemViewModel && element is WinoThreadMailItemViewModelListViewItem threadContainer)
         {
             threadContainer.Item = null;
-            threadContainer.IsSelected = false;
             threadContainer.IsThreadExpanded = false;
         }
     }

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

@@ -1,4 +1,3 @@
-using System.ComponentModel;
 using CommunityToolkit.WinUI;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
@@ -23,26 +22,17 @@ public partial class WinoMailItemViewModelListViewItem : ListViewItem
 
     partial void OnItemPropertyChanged(DependencyPropertyChangedEventArgs e)
     {
-        // TODO: This slows down. Optimize later.
+        if (e.OldValue is MailItemViewModel oldItem)
-        if (e.OldValue is MailItemViewModel oldMailItemViewModel) UnregisterPropertyChanged(oldMailItemViewModel);
+            oldItem.OnSelectionChanged = null;
-        if (e.NewValue is MailItemViewModel newMailItemViewModel) RegisterPropertyChanged(newMailItemViewModel);
 
-        if (e.NewValue is MailItemViewModel mailItemViewModel)
+        if (e.NewValue is MailItemViewModel newItem)
-            IsCustomSelected = mailItemViewModel.IsSelected;
-        else
-            IsCustomSelected = false;
-    }
-
-    private void RegisterPropertyChanged(MailItemViewModel model) => model.PropertyChanged += ModelPropertyChanged;
-    private void UnregisterPropertyChanged(MailItemViewModel model) => model.PropertyChanged -= ModelPropertyChanged;
-
-    private void ModelPropertyChanged(object? sender, PropertyChangedEventArgs e)
-    {
-        if (sender is not MailItemViewModel mailItemViewModel) return;
-
-        if (e.PropertyName == nameof(MailItemViewModel.IsSelected))
         {
-            IsCustomSelected = mailItemViewModel.IsSelected;
+            newItem.OnSelectionChanged = (selected) => IsCustomSelected = selected;
+            IsCustomSelected = newItem.IsSelected;
+        }
+        else
+        {
+            IsCustomSelected = false;
         }
     }
 }

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

@@ -1,4 +1,3 @@
-using System.ComponentModel;
 using System.Linq;
 using CommunityToolkit.WinUI;
 using Microsoft.UI.Xaml;
@@ -40,20 +39,17 @@ public partial class WinoThreadMailItemViewModelListViewItem : ListViewItem
 
     partial void OnItemPropertyChanged(DependencyPropertyChangedEventArgs e)
     {
-        if (e.OldValue is ThreadMailItemViewModel oldMailItemViewModel) UnregisterPropertyChanged(oldMailItemViewModel);
+        if (e.OldValue is ThreadMailItemViewModel oldItem)
-        if (e.NewValue is ThreadMailItemViewModel newMailItemViewModel) RegisterPropertyChanged(newMailItemViewModel);
+            oldItem.OnSelectionChanged = null;
-    }
 
-    private void RegisterPropertyChanged(ThreadMailItemViewModel model) => model.PropertyChanged += ModelPropertyChanged;
+        if (e.NewValue is ThreadMailItemViewModel newItem)
-    private void UnregisterPropertyChanged(ThreadMailItemViewModel model) => model.PropertyChanged -= ModelPropertyChanged;
-
-    private void ModelPropertyChanged(object? sender, PropertyChangedEventArgs e)
-    {
-        if (sender is not ThreadMailItemViewModel mailItemViewModel) return;
-
-        if (e.PropertyName == nameof(ThreadMailItemViewModel.IsSelected))
         {
-            IsCustomSelected = mailItemViewModel.IsSelected;
+            newItem.OnSelectionChanged = (selected) => IsCustomSelected = selected;
+            IsCustomSelected = newItem.IsSelected;
+        }
+        else
+        {
+            IsCustomSelected = false;
         }
     }
 }