protected override void OnItemAdded(SolutionConfiguration conf)
 {
     if (parentSolution != null)
     {
         conf.ParentSolution = parentSolution;
         parentSolution.NotifyConfigurationsChanged();
     }
     base.OnItemAdded(conf);
 }
 protected override void OnItemsAdded(IEnumerable <SolutionConfiguration> confs)
 {
     if (parentSolution != null)
     {
         foreach (var conf in confs)
         {
             conf.ParentSolution = parentSolution;
         }
         parentSolution.NotifyConfigurationsChanged();
     }
     base.OnItemsAdded(confs);
 }