List view radio buton not selecting when selected - flutter

Question

When i run the program on a device when i tick 2nd or 3rd term it does not take effect.
I am developing an Electronic student attendance tracking system so i decided to use a radio to track the term and also use check box to track the attendance that is checked if the student is present and unchecked if the student is not present but when i check the term radio it gives the correct output on the console but does not take effect on the physical screen.
import 'package:flutter/material.dart';
import 'package:atttendance_register/dataFiles/pupils.dart';
import 'package:atttendance_register/dataFiles/attendance.dart';
import 'package:intl/intl.dart';
class attendance extends StatefulWidget {
static Future<void> show(BuildContext context) async {
await Navigator.of(context).push(
MaterialPageRoute(builder: (context)=>attendance(),fullscreenDialog: true),
);
}
#override
_attendanceState createState() => _attendanceState();
}
class _attendanceState extends State<attendance> {
// final List<Pupils> pupils =[
// Pupils('John', ' Doe', 'Brad', 'Male', '001', DateTime.now(), '21'),
// Pupils('Jane', ' Doe', 'Mary', 'Female', '002', DateTime.now(), '21'),
// Pupils('Mohamed', ' James', '', 'Male', '003', DateTime.now(), '33'),
// Pupils('Titus', ' Nabieu', 'Jusu', 'Male', '004', DateTime.now(), '21'),
// Pupils('Steven', ' kai', 'Rogers', 'Male', '005', DateTime.now(), '21'),
// Pupils('Josephine', ' Bah', 'Neneh', 'Female', '006', DateTime.now(), '23')
//
// ];
final List<Attendance> attendance =[
Attendance(false,'John Doe Brad',DateTime.now(),0),
Attendance(true,'Jane Doe Mary',DateTime.now(),2),
Attendance(false,'Mohamed James',DateTime.now(),1),
Attendance(false,'Titus Nabieu Jusu',DateTime.now(),2),
Attendance(false,'Steven kai Rogers',DateTime.now(),2),
Attendance(false,'Josephine Bah Neneh',DateTime.now(),1)
];
bool selectedCheck = false;
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Enter Attendance'),
backgroundColor: Colors.blue[900],
),
backgroundColor: Colors.blue[100],
body:Container(
child: ListView.builder(
itemCount:attendance.length,
itemBuilder:(BuildContext context, int index){
int selectedRadio = attendance[index].Term;
bool selectedCheck = attendance[index].attendance;
return Container(
child: Card(
child: Column(
//final pupil =pupils[index];
children: <Widget>[
Text(attendance[index].pupilName),
Text('Select Term'),
Row(
children: <Widget>[
Radio(
value:0,
groupValue: selectedRadio,
activeColor: Colors.blue,
onChanged: (T){
print(T);
setState(() {selectedRadio = T;}
);},
),
new Text(
'1st Term'
),
new Radio(
value: 1,
groupValue: selectedRadio,
activeColor: Colors.blue,
onChanged: (T){
print(T);
setState(() {selectedRadio = T;}
);
},
),
new Text(
'2nd Term'
),
new Radio(
value: 2,
groupValue: selectedRadio,
activeColor: Colors.blue,
onChanged: (T){
print(T);
setState(() {selectedRadio = T;}
);
},
),
new Text(
'3rd Term',
),
],
),
Row(
children: <Widget>[
Checkbox(
value: selectedCheck,
activeColor: Colors.blue,
onChanged: (bool value){
print(value);
setState(() {selectedCheck = value;}
);},
),
new Text(
'Present'
),
],
),
],
),
),
);
} ,),
),
);
}
// Widget pupilsCard(BuildContext context, int index){
// final pupil =pupils[index];
// bool selectedRadio = false;
//
// return Container(
// child: Card(
// child: Column(
// children: <Widget>[
// Text(pupil.FirstName+' '+pupil.OtherName+' '+pupil.LastName),
// Text('Select Term'),
// Row(
// children: <Widget>[
//
//
// ],
// ),
// Checkbox(
// value: selectedRadio,
// activeColor: Colors.blue,
// onChanged: (bool value){
// print(value);
// setState(() {selectedRadio = value;}
// );},
// ),
// new Text(
// 'Present'
//
// ),
// ],
// ),
// ),
// );
// }
}

Answer 1

In the onChanged property of your Radio widgets and your Checkbox widget, you are assigning the user selected value to the variable selectedRadio / selectedCheck and here is the problem, because when the new State is created through setState, the ListView is rebuilding and you are reassigning selectedRadio / selectedCheck the old value of the objects in this lines:
int selectedRadio = attendance[index].Term;
bool selectedCheck = attendance[index].attendance;
So you were not changing the actual value of the objects in the List, but you have too:
onChanged: (T) {
print(T);
setState(() => attendance[index].Term = T);
},
and
onChanged: (value) {
print(value);
setState(() => attendance[index].attendance = value);
},