private void OnProblemOverviewOpened(OpenOverviewMessage obj)
 {
     // temporary .. use this code for ProblemOverviewViewModel and DeviceOverviewViewModel instead
     if (CurrentEmployee.AccountTypeOfCurrentEmployee() == "IT-manager")
     {
         ShowAddButton  = false;
         ShowEditButton = false;
     }
     else
     {
         ShowAddButton  = true;
         ShowEditButton = true;
     }
 }
 private void OnDeviceTypeOverviewOpened(OpenOverviewMessage obj)
 {
     ShowAddButton  = true;
     ShowEditButton = true;
 }