Flutter Multi Select throws setState() called after dispose(): - flutter

Question

I have following 2 drop down in my code
one is drodown and other one is multi select drop down
dropdownButtonFormField(
value: dropdownValueLvl,
decoration: InputDecoration(
prefixIcon: Icon(Icons.leaderboard_outlined),
),
isExpanded: true,
hint: Text('Location'),
onChanged: (String value) {
// This is called when the user selects an item.
// dropdownValueLvl = value;
if (mounted) {
setState(() {
dropdownValueLvl = value;
_selectedRoles;
});
}
},
validator: (String value) {
if (value?.isEmpty ?? true) {
return 'Please select Location ';
}
return null;
},
items: _locddl.map((item) {
return DropdownMenuItem<String>(
value: item.id,
child: Text(item.locationyName),
);
}).toList(),
),
FutureBuilder(
future:
Provider.of<Salesmans>(context, listen: false)
.getUser(),
builder: (BuildContext context,
AsyncSnapshot<Salesman> snapshot) {
if (snapshot.connectionState ==
ConnectionState.done) {
return MultiSelectField<DdlValues>(
//key: _multiSelectKey,
// initialValue: _listRoles
// .where((element) => _editeSalesman.ddlRoles
// .contains((element).id))
// .toList(),
initialValue: _selectedRoles,
buttonText: 'Select Roles',
title: 'Select Roles',
stream: _listRoles,
onConfirm: (values) {
_selectedRoles = values;
});
} else {
return CircularProgressIndicator();
}
}),
All crud operation are performed properly but If I validate form and select Normal drop down and then select value from multi select drop down, It throws setState() called after dispose():
MultiSelectField.dart as follow
class MultiSelectField<V extends DdlValues> extends StatefulWidget {
final List<V> stream;
final List<V> initialValue;
final FormFieldSetter<List<V>> onConfirm;
final String buttonText;
final String title;
const MultiSelectField({
Key key,
#required this.stream,
#required this.initialValue,
#required this.onConfirm,
#required this.buttonText,
#required this.title,
}) : super(key: key);
#override
_MultiSelectFieldState createState() => _MultiSelectFieldState<V>();
}
class _MultiSelectFieldState<V extends DdlValues>
extends State<MultiSelectField<V>> {
#override
Widget build(BuildContext context) {
// return StreamBuilder(
// stream: widget.stream,
// builder: (BuildContext context, AsyncSnapshot<List<V>> snapshot) {
print(widget.initialValue);
print("Mainwid Key" + widget.key.toString());
//MultiSelectDialogField
return MultiSelectDialogField(
// key: widget.key,
buttonText: Text(widget.buttonText),
title: Text(widget.title),
items: widget.stream
.map((item) => MultiSelectItem(item, item.name))
.toList(),
initialValue: widget.initialValue,
onConfirm: widget.onConfirm,
listType: MultiSelectListType.LIST,
validator: (List value) {
if (value?.isEmpty ?? true) {
return 'Please select Roles ';
}
return null;
},
);
// });
}
}

Answer 1

Earlier in My code, If I validate then following save was called
Future<void> _saveForm() async {
final isValid = _form.currentState.validate();
FocusScope.of(context).unfocus(); // This line was causing issue
bool isSuccess = true;
if (!isValid) {
return;
}
// save code
}
If Validate form and select Dropdown value and then Multi select value was throwing setState() called after dispose():
I changed code as below and now its working
Future<void> _saveForm() async {
final isValid = _form.currentState.validate();
bool isSuccess = true;
if (!isValid) {
return;
}
FocusScope.of(context).unfocus(); // move this line to after if condition
// save code
}