private void Add_Button_Click(object sender, RoutedEventArgs e)
        {
            //MessageBox.Show("Добавление новой записи");
            var DataContextdf = new ViewModel.MainViewModel();

            DataContextdf.Add_new_human(NewName.Text.ToString(), NewPatr.Text.ToString(), NewLastName.Text.ToString(), NewEmailAdress.Text.ToString(), humans);
        }
        private void Load_Button_Click(object sender, RoutedEventArgs e)
        {
            //MessageBox.Show("Загрузка данных из xml");
            var DataContextdf = new ViewModel.MainViewModel();

            humans.Clear();
            humans = DataContextdf.Load_xml();

            humansGrid.DataContext = humans;
        }
        private void Save_Button_Click(object sender, RoutedEventArgs e)
        {
            var DataContextdf = new ViewModel.MainViewModel();

            DataContextdf.Save_xml(humans);
        }