How to group list of Radio buttons from string array. Radio Button when clicked is pointed in all items. Radio list tile is selected in all items

Question

I am using flutter-SQLite-Dart to develop a mobile application. with radio list tile I have assigned a radio button and passed a value of index. When executing the application I am able to click all the radio buttons. I need to make the list of radio buttons to be clickable only once, when I have selected one radio button the others should not be selected. This is the requirement.

return InkWell(
            onTap: press,
            child: Container(
              child: Row(
                children: <Widget>[
                  Expanded(
                    child: Container(
                        height: 60.0,
                        child: Theme(
                          data: Theme.of(context).copyWith(
                              unselectedWidgetColor: Colors.grey,
                              disabledColor: Colors.blue),
                          child: Column(children: [
                        
                            RadioListTile(
                              title: Text("${sample[index]}",
                                  style:
                                  TextStyle(color: Colors.black)),
                              groupValue: id,
                              value: index,
                              activeColor: Colors.green,
                              onChanged: (val) {
                                setState(() {
                                  id = val;
                                  debugPrint('val answer$val');
                                });
                              },
                              toggleable: true,
                            ),
                          ]),
                        )),
                  ),
                  ],
              ),
            ),
          );

The output of the application

Answer 1

Hi Please check my answer below. I have used statefull widget.

import 'package:flutter/material.dart';

class RadioList extends StatefulWidget {
  final List<String> list;
  final ValueChanged<int>? selectedIndex;

  RadioList(this.list, this.selectedIndex);

  @override
  _RadioListState createState() => _RadioListState();
}

class _RadioListState extends State<RadioList> {

  int currentIndex = -1;

  @override
  Widget build(BuildContext context) {
    return ListView.separated(
      itemCount: widget.list.length,
      itemBuilder: (_, index) {
        String value = widget.list[index];
        return Row(
          mainAxisSize: MainAxisSize.min,
          children: [

            Radio(value: index, groupValue: currentIndex, onChanged: (flag) {
              setState(() {
                currentIndex = index;
              });
            }),
            Text(value)
          ],
        );
      }, separatorBuilder: (_, index) {
      return SizedBox(height: 10,);
    },);
  }
}

Answer 2

Try below code, you will declare a String with groupValue.

String _groupValue;

return InkWell(
            onTap: press,
            child: Container(
              child: Row(
                children: <Widget>[
                  Expanded(
                    child: Container(
                        height: 60.0,
                        child: Theme(
                          data: Theme.of(context).copyWith(
                              unselectedWidgetColor: Colors.grey,
                              disabledColor: Colors.blue),
                          child: Column(children: [
                        
                            RadioListTile(
                              title: Text("${sample[index]}",
                                  style:
                                  TextStyle(color: Colors.black)),
                              groupValue: _groupValue,
                              value: index,
                              activeColor: Colors.green,
                              onChanged: (val) {
                                setState(() {
                                   _groupValue = val;
                                  debugPrint('val answer$val');
                                });
                              },
                          
                            ),
                          ]),
                        )),
                  ),
                  ],
              ),
            ),
          );