如何扩展CalendarView以允许选择多个日期？

public class CustomCalendarView extends CalendarView {
    private HashSet<Date> selectedDates;

    public CustomCalendarView(Context context) {
        super(context);
        selectedDates = new HashSet<>();
    }

    public CustomCalendarView(Context context, AttributeSet attrs) {
        super(context, attrs);
        selectedDates = new HashSet<>();
    }

    @Override
    public void setOnDateChangeListener(OnDateChangeListener listener) {
        super.setOnDateChangeListener((view, year, month, dayOfMonth) -> {
            Calendar selectedDate = Calendar.getInstance();
            selectedDate.set(year, month, dayOfMonth);
            Date date = selectedDate.getTime();

            if (selectedDates.contains(date)) {
                selectedDates.remove(date);
            } else {
                selectedDates.add(date);
            }

            // 可选：更新选中日期的视觉效果

            listener.onSelectedDayChange(view, year, month, dayOfMonth);
        });
    }

    public HashSet<Date> getSelectedDates() {
        return selectedDates;
    }

    public void clearSelectedDates() {
        selectedDates.clear();
    }
}