diff --git a/Controls/Avalonia/NavigationView/NavigationViewItem.cs b/Controls/Avalonia/NavigationView/NavigationViewItem.cs
index b70d865..357fabf 100644
--- a/Controls/Avalonia/NavigationView/NavigationViewItem.cs
+++ b/Controls/Avalonia/NavigationView/NavigationViewItem.cs
@@ -9,7 +9,7 @@ public class NavigationViewItem : FluentAvalonia.UI.Controls.NavigationViewItem,
 {
     private NavigationView? navigationView;
 
-    public event EventHandler<NavigationViewItemInvokedEventArgs> Invoked;
+    public event EventHandler<NavigationViewItemInvokedEventArgs>? Invoked;
 
     Type IStyleable.StyleKey => typeof(FluentAvalonia.UI.Controls.NavigationViewItem);
 
diff --git a/Controls/Avalonia/SettingsExpander/SettingsExpander.cs b/Controls/Avalonia/SettingsExpander/SettingsExpander.cs
new file mode 100644
index 0000000..6825d54
--- /dev/null
+++ b/Controls/Avalonia/SettingsExpander/SettingsExpander.cs
@@ -0,0 +1,8 @@
+using Avalonia.Styling;
+
+namespace Toolkit.Controls.Avalonia;
+
+public class SettingsExpander : FluentAvalonia.UI.Controls.SettingsExpander, IStyleable
+{
+    Type IStyleable.StyleKey => typeof(FluentAvalonia.UI.Controls.SettingsExpander);
+}
\ No newline at end of file