idSource = SMESH::SObjectToInterface<SMESH::SMESH_IDSource>( sobj );
if ( !idSource->_is_nil() ) {
SMESH::array_of_ElementType_var types = idSource->GetTypes();
idSource = SMESH::SObjectToInterface<SMESH::SMESH_IDSource>( sobj );
if ( !idSource->_is_nil() ) {
SMESH::array_of_ElementType_var types = idSource->GetTypes();