public static MyServiceClass GetMyServiceClassInstance()
 {
     if (serviceInstance == null) {
         serviceInstance = new MyServiceClass();
     }
     return serviceInstance;
 }
 public MainWindow()
 {
     InitializeComponent();
     service = MyServiceClass.GetMyServiceClassInstance();
     UpdateQuestionnairsDataGrids();
     string[] regionsStrings = new[] {"Hovedstaden", "Sjælland", "Syddanmark", "Midtjylland", "Nordjylland"};
     RegionComboBox.ItemsSource = regionsStrings;
     UpdateUserSelectionDataGrid("", "", "");
     PercentageComplete.Content = service.GetPercentageComplete();
 }