private void bIzmeniUpl_Click(object sender, RoutedEventArgs e)
        {
            Uplata selectedUplata = dgUplate.SelectedItem as Uplata;

            UplateEditWindow uew = new UplateEditWindow(selectedUplata, MOD.IZMENA);

            uew.ShowDialog();
        }
        private void bDodajUpl_Click(object sender, RoutedEventArgs e)
        {
            Uplata uplata = new Uplata();

            UplateEditWindow uew = new UplateEditWindow(uplata);

            uew.ShowDialog();
        }