public MainWindow()
        {
            InitializeComponent();
            OtpremnicaClient service = new OtpremnicaClient();
            var poc = new PocetnaOtpremnicaViewModel(service);

            this.DataContext = poc;
        }
        public EditOtpremnice(PocetnaOtpremnicaViewModel GridSelectedItem, ObservableCollection <PocetnaOtpremnicaViewModel> AllZaglavlja, ObservableCollection <double> GetSumVerdnostiDokumenata)
        {
            InitializeComponent();

            var dodavanje = new EditujOtpremnicuViewModel(GridSelectedItem, AllZaglavlja, GetSumVerdnostiDokumenata);

            this.DataContext = dodavanje; // ovde se daje DataContext

            if (dodavanje.CloseAction == null)
            {
                dodavanje.CloseAction = new Action(() => this.Close());
            }
        }