public MainWindow()
{
InitializeComponent();
bl = MyBL.Instance;
comboBoxDiscpline.DataContext = Enum.GetNames(typeof(Enums.Discipline)).ToList();
_SpecialityCollection = new ObservableCollection <Speciality>(bl.getSpecsList());
dgSpecialities.DataContext = _SpecialityCollection;
_WorkersCollection = new ObservableCollection <Worker>(bl.getWorkersList());
lbWorkers.DataContext = _WorkersCollection;
}