protected override void OnWindowLoaded(object sender, RoutedEventArgs e)
{
base.OnWindowLoaded(sender, e);
var cellInfo = new DataGridCellInfo(TableData.Items[0], TableData.Columns[0]);
TableData.SelectedCells.Clear();
TableData.SelectedCells.Add(cellInfo);
TableData.CurrentCell = cellInfo;
TableData.BeginEdit();
}