summary method Null safety

SummaryStatics summary()

Implementation

SummaryStatics summary() {
  final s = _getCardsSchedule()!;
  final summary = SummaryStatics(
      later: s.later!.length,
      due: s.due!.length,
      overdue: s.overdue!.length,
      learning: s.learning!.length);

  return summary;
}