private void setVendorsToSelected(string itemName)
        {
            //Adds selected Vendors to the selected Item
            foreach (String vendor in lstItemVendors.ItemsSource)
            {
                try
                {
                    _inventoryManager.AddVendorItem(itemName, vendor);
                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.Message + "\n\n" + ex.InnerException.Message,
                                    "Vendor " + vendor + " for Item, Could Not Be Added", MessageBoxButton.OK, MessageBoxImage.Error);
                }
            }

            //No need to set preferred vendor if no preference
            if (!(cmbPreferredVendor.SelectedItem.ToString() == noPreferenceText))
            {
                try
                {
                    _vendorManager.SetPreferredVendor(itemName, cmbPreferredVendor.SelectedItem.ToString());
                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.Message + "\n\n" + ex.InnerException.Message,
                                    "Preferred Vendor Could Not Be Set", MessageBoxButton.OK, MessageBoxImage.Error);
                }
            }
        }