private void onKeyUp(object sender, KeyEventArgs e)
        {
            Console.WriteLine("Keyup");

            if (e.Key == Key.LeftAlt)
            {
                this.Hide();

                if (lbTodoList.SelectedItem != null)
                {
                    var proc = (lbTodoList.SelectedItem as DesktopWindow);
                    WinAPI.SetForegroundWindow(proc.ProcessId);

                    lbTodoList.ItemsSource = DesktopWindow.Promote(proc);
                    var view = CollectionViewSource.GetDefaultView(lbTodoList.ItemsSource);
                    view.Refresh();
                }
            }
        }