public void DeleteTransactionType(TransactionType transactionType)
 {
     throw new NotImplementedException();
 }
 private void DeleteTransactionType(TransactionType obj)
 {
     if(MessageBox.Show("Are you sure you want to delete this expence type?", string.Empty, MessageBoxButton.OKCancel)==MessageBoxResult.Cancel)
         return;
     _dataSource.Transactions.Where(x=> x.TransactionType != null && x.TransactionType.Id == obj.Id).ToList().ForEach(x=>x.TransactionType = null);
     _dataSource.DeleteTransactionType(obj);
     RaisePropertyChanged(() => TransactionTypes);
 }
 public void DeleteTransactionType(TransactionType transactionType)
 {
     transactionType.IsDeleted = true;
     SubmitChanges();
 }