dateDecrease method
Implementation
void dateDecrease({int day = 1}) {
var firstDate = (DateTime.now().subtract(Duration(days: durationDays)));
var decreased = (inputDate ?? DateTime.now()).subtract(Duration(days: day));
if (decreased.isAfter(firstDate)) {
_disablePrevious.value = false;
onChanged?.call(decreased);
} else {
_disablePrevious.value = true;
onChanged?.call(firstDate);
}
}