Workspace.OpenDocument does nothing

[codehunter13]

Version Used:
3.5.0.0

Steps to Reproduce:
_workspace is a visualstudio namespace. when calling following function, the newly added document is not opened.

 public void AddDocument(Project proj, string ns, string className, string txt, bool openFile)
        {
            var newDoc = proj.AddDocument(
                className + ".cs",
                txt,
                Code.GetFolders(proj.Name, ns)
                );
            if (!_workspace.TryApplyChanges(newDoc.Project.Solution))
                throw new Exception("Failed to apply changes to workspace");

            if (openFile && _workspace.CanOpenDocuments)
            {
                _workspace.OpenDocument(newDoc.Id, true);
            }
        }

Expected Behavior:
newly added document should be opened in visual studo

Actual Behavior:i
nothing happens, also no exception

[CyrusNajmabadi]

Can you debug through to see why it's not working?