private void CancelButton_Click(object sender, RoutedEventArgs e)
 {
     OnCanceling();
     if (_dialogResult == true)
     {
         if (TLDataForm != null)
         {
             //RaiseCanExecuteChanged();
             //NavStateTrue();
             TLDataForm.CancelEdit();
             //  TLDataForm.TLDataForm.BeginEdit();
         }
     }
 }
 private void NextButton_Click(object sender, RoutedEventArgs e)
 {
     TLDataForm.MoveCurrentToNext();
 }
 private void PreviousButton_Click(object sender, RoutedEventArgs e)
 {
     TLDataForm.MoveCurrentToPrevious();
 }
 private void addButton_Click(object sender, RoutedEventArgs e)
 {
     //NavStateFalse();
     TLDataForm.AddNewItem();
 }