FluentTest.TestWindow.OnBlackClick C# (CSharp) Method

        private void OnBlackClick(object sender, RoutedEventArgs e)
        {
            Dispatcher.BeginInvoke(DispatcherPriority.ApplicationIdle, (ThreadStart)(() =>
            {
                Application.Current.Resources.BeginInit();
                Application.Current.Resources.MergedDictionaries.RemoveAt(1);
                Application.Current.Resources.MergedDictionaries.Add(new ResourceDictionary { Source = new Uri("pack://application:,,,/Fluent;component/Themes/Office2010/Black.xaml") });                
                Application.Current.Resources.EndInit();
            }));
        }