Visual Studio Add-in development - Get directory path within a C++ project

i'm currently trying to build an add-in which is similar to VSNewFile. So it's just a simple extension which provides a faster way to create new files. The problem with VSNewFile is that it doesn't work for C++ projects and i need it for that.

Here is my problem:

I'm unable to retrieve the absolute path of a selected directory. All samples i've found were something like that:

(string)((ProjectItem)parent).Properties.Item("FullPath").Value;

While this is working in a C# project it isn't in a C++ project. In an C++ project selectedItem.Project and selectedItem.ProjectItem are both null when i select a directory.

Important: I'm not talking about filters! I mean real directories.

Any help is welcome. I've searched for hours now without success开发者_C百科.

Thanks

Maybe this will help anyone else who got the same problem:
http://social.msdn.microsoft.com/forums/en-US/vsx/thread/bd738463-ba24-4880-beea-f3ec110d981e

// Subscribe to the SVsShellMonitorSelection service somewhere:  
public void mySetupMethod()  
{  
     IVsMonitorSelection monitorSelection = 
     (IVsMonitorSelection)Package.GetGlobalService(
     typeof(SVsShellMonitorSelection));     
     monitorSelection.AdviseSelectionEvents(this, out cookie);    
}  

// This class (as used in AdviseSelection) must implement the IVsSelectionEvents interface  
// To get the folder path use the following  
public int OnSelectionChanged(IVsHierarchy pHierOld, uint itemidOld,   
  IVsMultiItemSelect pMISOld, ISelectionContainer pSCOld,   
  IVsHierarchy pHierNew, uint itemidNew, IVsMultiItemSelect pMISNew, ISelectionContainer pSCNew)  
{  
  string fullPath;  
  // Get the full path
  pHierNew.GetCanonicalName(itemidNew, out fullPath);  

  // Do something with the path...  
  return VSConstants.S_OK;  
}