Flutter get all variable null using selector provider - flutter

Question

I have this provider class:
import 'package:flutter/material.dart';
class DateProvider with ChangeNotifier {
DateTime? _date1 = null;
DateTime? _date2 = null;
DateTime? get date1 => _date1;
DateTime? get date2 => _date2;
void changeDate1(DateTime? date1) {
_date1 = date1;
notifyListeners();
}
void changeDate2(DateTime? date2) {
_date2 = date2;
notifyListeners();
}
}
I have two TextFormFields wrapped with Selector when I press on the first one to pick date
class _TestState extends State<Test> {
var _formKey = GlobalKey<FormState>();
var _date2Key = GlobalKey<FormState>();
TextEditingController _date1Controller = TextEditingController();
TextEditingController _date2Controller = TextEditingController();
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(),
body: Form(
key: _formKey,
child: Column(
children: [
Selector<DateProvider, DateTime?>(
selector: (_, provider) => provider.date1,
builder: (context, date1, child) {
return TextFormField(
controller: _date1Controller,
autovalidateMode: AutovalidateMode.onUserInteraction,
validator: (value) {
print("Validator $date1");
return;
},
readOnly: true,
onTap: () async {
DateTime? pickedDate = await showDatePicker(
context: context,
initialDate: date1 != null ? date1 : DateTime.now(),
firstDate: DateTime.now(),
lastDate: DateTime(2101),
);
if (pickedDate != null) {
Provider.of<DateProvider>(context, listen: false)
.changeDate1(pickedDate);
print("TextFormField1 date: $date1");
_date2Key.currentState!.validate();
_formKey.currentState!.validate();
}
},
);
}),
Selector<DateProvider, Tuple2<DateTime?, DateTime?>>(
selector: (_, provider) =>
Tuple2(provider.date1, provider.date2),
builder: (context, data, child) {
return Form(
key: _date2Key,
child: TextFormField(
controller: _date2Controller,
autovalidateMode: AutovalidateMode.onUserInteraction,
validator: (value) {
print("Validator2 date1 :${data.item1}");
print("Validator2 date2 :${data.item2}");
return;
},
readOnly:
true, //set it true, so that user will not able to edit text
onTap: () async {
DateTime? pickedDate = await showDatePicker(
context: context,
initialDate:
data.item2 != null ? data.item2! : DateTime.now(),
firstDate: DateTime.now(),
lastDate: DateTime(2101),
);
if (pickedDate != null) {
Provider.of<DateProvider>(context, listen: false)
.changeDate2(pickedDate);
}
},
),
);
}),
],
),
),
);
}
}
I want to change the date1 in provider class and validate that two textfromfield.
When I pickDate in the first one all the date printed is null knowing that I wrapped the two textformfield with selector
The console shows:
TextFormField1 date: null
Validator2 date1 :null
Validator2 date2 :null
Validator null
why are the values null