TextBoxLineCountBehavior: Fixed issue with UpdateAttachedProperties b…

…eing called after detached causing NullReferenceException (#3769)
MaterialDesignInXAML · Jan 13, 2025 · 0ff7d5d · 0ff7d5d
1 parent 32e2584
commit 0ff7d5d
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/src/MaterialDesignThemes.Wpf/Behaviors/TextBoxLineCountBehavior.cs b/src/MaterialDesignThemes.Wpf/Behaviors/TextBoxLineCountBehavior.cs
@@ -12,8 +12,11 @@ public class TextBoxLineCountBehavior : Behavior<TextBox>
 
     private void UpdateAttachedProperties()
     {
-        AssociatedObject.SetCurrentValue(TextFieldAssist.TextBoxLineCountProperty, AssociatedObject.LineCount);
-        AssociatedObject.SetCurrentValue(TextFieldAssist.TextBoxIsMultiLineProperty, AssociatedObject.LineCount > 1);
+        if (AssociatedObject != null)
+        {
+            AssociatedObject.SetCurrentValue(TextFieldAssist.TextBoxLineCountProperty, AssociatedObject.LineCount);
+            AssociatedObject.SetCurrentValue(TextFieldAssist.TextBoxIsMultiLineProperty, AssociatedObject.LineCount > 1);
+        }
     }
 
     protected override void OnAttached()