DragAndDrop core

Lattice.Themes.Core/WindowTracker.cs

@@ -0,0 +1,18 @@
+using Microsoft.UI.Xaml;
+
+namespace Lattice.Themes;
+
+public static class WindowTracker
+{
+    private static readonly List<Window> _windows = new();
+
+    public static IReadOnlyList<Window> Windows => _windows;
+
+    public static void Register(Window window)
+    {
+        if (!_windows.Contains(window))
+            _windows.Add(window);
+
+        window.Closed += (_, _) => _windows.Remove(window);
+    }
+}