private void ImportThread() { _timetable = _importer.ImportTimetable(); Invoke(new MethodInvoker(delegate { if (_timetable != null) { // build relational data _timetable.BuildEquivalency(); _timetable.BuildCompatibility(); Next(); } else { MessageBox.Show("Failed to import timetable data.", "Import", MessageBoxButtons.OK, MessageBoxIcon.Exclamation); Close(); } })); }