first commit

ClassicAssist.Updater/Misc/CloseBehaviour.cs

@@ -0,0 +1,33 @@
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Interactivity;
+
+namespace ClassicAssist.Updater
+{
+    public class CloseBehaviour : Behavior<Button>
+    {
+        protected override void OnAttached()
+        {
+            base.OnAttached();
+
+            AssociatedObject.Click += OnClick;
+        }
+
+        protected override void OnDetaching()
+        {
+            AssociatedObject.Click -= OnClick;
+        }
+
+        private void OnClick( object sender, RoutedEventArgs e )
+        {
+            if ( !( sender is Button button ) )
+            {
+                return;
+            }
+
+            Window window = Window.GetWindow( button );
+
+            window?.Close();
+        }
+    }
+}