private void editContractorBtn_Click(object sender, RoutedEventArgs e)
 {
     ContractorInfo contractorToEdit = GetSelectedItem();
     if (contractorToEdit != null)
     {
         ECMS.AddContractor AddContractorObj = new ECMS.AddContractor(contractorToEdit);
         AddContractorObj.Show();
     }
 }
 private void addContractorBtn_Click(object sender, RoutedEventArgs e)
 {
     ECMS.AddContractor AddContractorObj = new ECMS.AddContractor(null);
     AddContractorObj.Show();
 }