I am trying to use CheckBox in flutter, but I am facing a problem using setState inside of it. This the code of the checkbox.
Checkbox(
value: check1,
checkColor: Colors.white,
activeColor: Colors.green,
onChanged: (bool? value1) {
State.setState(() {
check1 = value1;
});
},
),
And this is the whole code
// ignore_for_file: sized_box_for_whitespace, duplicate_ignore, avoid_unnecessary_containers, avoid_print
// ignore: unnecessary_import
import 'dart:ui';
import 'package:flutter/material.dart';
// ignore: must_be_immutable
class Register extends StatelessWidget {
var emailController = TextEditingController();
var passwordController = TextEditingController();
var firstNameController = TextEditingController();
var lastNameController = TextEditingController();
var userNameController = TextEditingController();
var confirmPasswordController = TextEditingController();
bool? check1 = false;
Register({super.key});
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
leading: const Icon(
Icons.menu,
),
actions: const [
IconButton(onPressed: sSearch, icon: Icon(Icons.search)),
IconButton(
onPressed: noNotification,
icon: Icon(Icons.notification_important_rounded),
)
],
centerTitle: true,
backgroundColor: const Color.fromARGB(255, 80, 146, 4),
elevation: 15,
),
body: Padding(
padding: const EdgeInsets.all(20.0),
child: Center(
child: SingleChildScrollView(
child:
Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
Container(
alignment: AlignmentDirectional.center,
child: const Text(
'Register',
style: TextStyle(fontSize: 40, fontWeight: FontWeight.bold),
),
),
const SizedBox(
height: 40,
),
Row(
children: [
Expanded(
child: TextFormField(
controller: firstNameController,
keyboardType: TextInputType.text,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.person),
labelText: 'First Name',
border: OutlineInputBorder()),
),
),
Expanded(
child: TextFormField(
controller: lastNameController,
keyboardType: TextInputType.text,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.person),
labelText: 'Last Name',
border: OutlineInputBorder()),
),
),
],
),
const SizedBox(
height: 10,
),
TextFormField(
controller: userNameController,
keyboardType: TextInputType.text,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.supervised_user_circle),
labelText: 'UserName',
border: OutlineInputBorder()),
),
const SizedBox(
height: 10,
),
TextFormField(
controller: emailController,
keyboardType: TextInputType.emailAddress,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.email),
labelText: 'Email Address',
border: OutlineInputBorder()),
),
const SizedBox(
height: 10,
),
TextFormField(
controller: passwordController,
keyboardType: TextInputType.visiblePassword,
obscureText: true,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.lock),
suffixIcon: Icon(Icons.remove_red_eye),
labelText: 'Password',
border: OutlineInputBorder()),
),
const SizedBox(
height: 10,
),
TextFormField(
controller: confirmPasswordController,
keyboardType: TextInputType.visiblePassword,
obscureText: true,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.lock),
suffixIcon: Icon(Icons.remove_red_eye),
labelText: 'Confirm Password',
border: OutlineInputBorder()),
),
const SizedBox(
height: 20,
),
Container(
width: double.infinity,
color: Colors.green,
child: MaterialButton(
onPressed: () {
print(emailController.text);
print(passwordController.text);
},
child: const Text(
'LOGIN',
style: TextStyle(
fontSize: 20,
fontWeight: FontWeight.bold,
color: Colors.white),
),
),
),
const SizedBox(
height: 10,
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Checkbox(
value: check1,
checkColor: Colors.white,
activeColor: Colors.green,
onChanged: (bool? value1) {
State.setState(() {
check1 = value1;
});
},
),
],
)
]),
),
),
),
);
}
}
void noNotification() {
// ignore: avoid_print
print('Notification Clicked');
}
void sSearch() {
// ignore: avoid_print
print('Search Clicked');
}
I didn't understand what was the problem, I would be appreciated if someone could explain it to me.
for using setstate your widget should be stateful widget check the code below
// ignore_for_file: sized_box_for_whitespace, duplicate_ignore, avoid_unnecessary_containers, avoid_print
import 'package:flutter/material.dart';
class Register extends StatefulWidget {
const Register({super.key});
@override
State<Register> createState() => _RegisterState();
}
class _RegisterState extends State<Register> {
var emailController = TextEditingController();
var passwordController = TextEditingController();
var firstNameController = TextEditingController();
var lastNameController = TextEditingController();
var userNameController = TextEditingController();
var confirmPasswordController = TextEditingController();
bool? check1 = false;
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
leading: const Icon(
Icons.menu,
),
actions: const [
IconButton(onPressed: sSearch, icon: Icon(Icons.search)),
IconButton(
onPressed: noNotification,
icon: Icon(Icons.notification_important_rounded),
)
],
centerTitle: true,
backgroundColor: const Color.fromARGB(255, 80, 146, 4),
elevation: 15,
),
body: Padding(
padding: const EdgeInsets.all(20.0),
child: Center(
child: SingleChildScrollView(
child:
Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
Container(
alignment: AlignmentDirectional.center,
child: const Text(
'Register',
style: TextStyle(fontSize: 40, fontWeight: FontWeight.bold),
),
),
const SizedBox(
height: 40,
),
Row(
children: [
Expanded(
child: TextFormField(
controller: firstNameController,
keyboardType: TextInputType.text,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.person),
labelText: 'First Name',
border: OutlineInputBorder()),
),
),
Expanded(
child: TextFormField(
controller: lastNameController,
keyboardType: TextInputType.text,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.person),
labelText: 'Last Name',
border: OutlineInputBorder()),
),
),
],
),
const SizedBox(
height: 10,
),
TextFormField(
controller: userNameController,
keyboardType: TextInputType.text,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.supervised_user_circle),
labelText: 'UserName',
border: OutlineInputBorder()),
),
const SizedBox(
height: 10,
),
TextFormField(
controller: emailController,
keyboardType: TextInputType.emailAddress,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.email),
labelText: 'Email Address',
border: OutlineInputBorder()),
),
const SizedBox(
height: 10,
),
TextFormField(
controller: passwordController,
keyboardType: TextInputType.visiblePassword,
obscureText: true,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.lock),
suffixIcon: Icon(Icons.remove_red_eye),
labelText: 'Password',
border: OutlineInputBorder()),
),
const SizedBox(
height: 10,
),
TextFormField(
controller: confirmPasswordController,
keyboardType: TextInputType.visiblePassword,
obscureText: true,
onFieldSubmitted: (String value) {
print(value);
},
onChanged: (String value) {
print(value);
},
decoration: const InputDecoration(
prefixIcon: Icon(Icons.lock),
suffixIcon: Icon(Icons.remove_red_eye),
labelText: 'Confirm Password',
border: OutlineInputBorder()),
),
const SizedBox(
height: 20,
),
Container(
width: double.infinity,
color: Colors.green,
child: MaterialButton(
onPressed: () {
print(emailController.text);
print(passwordController.text);
},
child: const Text(
'LOGIN',
style: TextStyle(
fontSize: 20,
fontWeight: FontWeight.bold,
color: Colors.white),
),
),
),
const SizedBox(
height: 10,
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Checkbox(
value: check1,
checkColor: Colors.white,
activeColor: Colors.green,
onChanged: (bool? value1) {
setState(() {
check1 = value1;
});
},
),
],
)
]),
),
),
),
);
}
}
void noNotification() {
// ignore: avoid_print
print('Notification Clicked');
}
void sSearch() {
// ignore: avoid_print
print('Search Clicked');
}