pickBirthDate method
Implementation
Future<void> pickBirthDate(BuildContext context) async {
final now = DateTime.now();
final initialDate = selectedDob.value ?? DateTime(now.year - 18, now.month, now.day);
final picked = await showDatePicker(
context: context,
initialDate: initialDate,
firstDate: DateTime(1900),
lastDate: now,
);
if (picked == null) return;
selectedDob.value = picked;
final dd = picked.day.toString().padLeft(2, '0');
final mm = picked.month.toString().padLeft(2, '0');
dobController.text = '$dd/$mm/${picked.year}';
}