private void btnAdd_Click(object sender, RoutedEventArgs e)
        {
            AddTravelDialog dlg = new AddTravelDialog(this);

            if (dlg.ShowDialog() == true)
            {
                RefreshList();
                MessageBox.Show("Success!");
            }
        }
        private void lvTravel_MouseDoubleClick(object sender, MouseButtonEventArgs e)
        {
            Travel currPerson = lvTravel.SelectedItem as Travel;

            if (currPerson == null)
            {
                return;
            }

            AddTravelDialog dlg = new AddTravelDialog(this);

            if (dlg.ShowDialog() == true)
            {
                RefreshList();
                MessageBox.Show("Seccess!");
            }
        }