internal override object GetCreatorElement()
 {
     var mrb = new MappingResultBinding(null, null, _mappingResultBindings);
     return mrb;
 }
 protected override LabelEditResult OnCreatorNodeEditCommitted(int index, object value, int insertIndex)
 {
     var columnName = value as string;
     if (!string.IsNullOrEmpty(columnName))
     {
         var mrb = new MappingResultBinding(null, null, _mappingResultBindings);
         if (mrb.CreateModelItem(null, _mappingResultBindings.Context, columnName))
         {
             DoBranchModification(BranchModificationEventArgs.InsertItems(this, insertIndex, 1));
             return LabelEditResult.AcceptEdit;
         }
         else
         {
             // attempt to create model item failed (no properties to map to)
             return LabelEditResult.CancelEdit;
         }
     }
     else
     {
         return LabelEditResult.CancelEdit;
     }
 }