Change checkbox state when clicking on another widget - flutter

Question

I have a goal to change the state of the checkbox when clicking on the adjacent widget. I tried to create a stateful function but unfortunately my code doesn't work.
Here is the function -
void _changeFlagCheckBox(bool? value){
setState(() {
MyCheckBoxCountry.isChecked = value!;
});
}
Inkwell - when you click on it, it should change the state of myCheckBoxCountry.
child: ListView.builder(
itemCount: city.length,
shrinkWrap: true
itemBuilder: (BuildContext context, int index) {
return InkWell(
onTap: () {
print(city[index]);
_changeFlagCheckBox;
},
child: Container(
margin: const EdgeInsets.only(top: 15),
child:Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children:[
Row(
children:[
SizeBox(width: 10,),
Text(city[index], style: TextStyle(color: ConfigColor.white, fontWeight: FontWeight.w500, fontSize: 15),)
],
),
MyCheckBoxCountry()
],
)
),
);
},
),
myCheckBoxCountry -
class MyCheckBoxCountry extends StatefulWidget {
static bool isChecked = false;
#override
_MyCheckBoxState createState() => _MyCheckBoxState();
}
class _MyCheckBoxState extends State<MyCheckBoxCountry> {
#override
Widget build(BuildContext context) {
return Theme(
data: Theme.of(context).copyWith(
unselectedWidgetColor: ConfigColor.grey,
),
child: Checkbox(
activeColor: ConfigColor.green,
checkColor: ConfigColor.background,
value: MyCheckBoxCountry.isChecked,
shape: CircleBorder(),
onChanged: (bool? value) {
setState(() {
MyCheckBoxCountry.isChecked = value!;
});
},
),
);
}
}

Answer 1

First of all you're not sending any value in your _changeFlagCheckBox function in your Inkwell so how is it supposed to change :
InkWell(
onTap: () {
print(city[index]);
_changeFlagCheckBox; //should be _changeFlagCheckBox(!MyCheckBoxCountry.isChecked)
},
but to understand why didn't you get an error like that, well that's because you made the bool value nullable in your _changeFlagCheckBox function:
void _changeFlagCheckBox(bool? value){ //should be (bool value)
setState(() {
MyCheckBoxCountry.isChecked = value!;
});
}
Though even then you are not using your isChecked value in your MyCheckBoxCountry class anywhere :
Checkbox(
activeColor: ConfigColor.green,
checkColor: ConfigColor.background,
value: MyCheckBoxCountry.isChecked,
shape: CircleBorder(),
onChanged: (bool? value) {
setState(() {
MyCheckBoxCountry.isChecked = value!; //should be the other way around
});
},
),
Should have been :
setState(() {
value = MyCheckBoxCountry.isChecked;
});

Answer 2

I guess since it is an another stateful widget class, It does not recognize the setState. Calling child widget from parent widget would solve the problem.