/// Find a root index which contains objects of the given document
/// \param theDoc the document object
//QModelIndex findDocumentRootIndex(const ModelAPI_Document* theDoc, int aColumn = 1) const;
/// Find a root index which contains objects of the given document
/// \param theDoc the document object
//QModelIndex findDocumentRootIndex(const ModelAPI_Document* theDoc, int aColumn = 1) const;