There is a token error when logging in to the flutter app - flutter

Question

I have a problem when I want to login in my flutter application. when you have entered your email and password then click the login button, it only processes loading but cannot go to the home page. and in android studio an error appears like the image I sent.
this is a picture of the running error
api_service.dart
import 'package:http/http.dart' as http;
import 'dart:convert';
import '../model/login_model.dart';
class APIService {
Future<LoginResponseModel> login(LoginRequestModel requestModel) async {
String url = "http://192.168.100.211:8080/login";
final response = await http.post(url, body: requestModel.toJson());
if (response.statusCode == 200 || response.statusCode == 400) {
return LoginResponseModel.fromJson(
json.decode(response.body),
);
} else {
throw Exception('Failed to load data!');
}
}
}
login_model.dart
class LoginResponseModel {
final String token;
final String error;
LoginResponseModel({this.token, this.error});
factory LoginResponseModel.fromJson(Map<String, dynamic> json) {
return LoginResponseModel(
token: json["token"] != null ? json["token"] : "",
error: json["error"] != null ? json["error"] : "",
);
}
}
class LoginRequestModel {
String email;
String password;
LoginRequestModel({
this.email,
this.password,
});
Map<String, dynamic> toJson() {
Map<String, dynamic> map = {
'email': email.trim(),
'password': password.trim(),
};
return map;
}
}
login_page.dart
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter_crud_api_sample_app/beranda/beranda_view.dart';
import '/api/api_service.dart';
import '/model/login_model.dart';
import '../ProgressHUD.dart';
class LoginPage extends StatefulWidget {
#override
_LoginPageState createState() => _LoginPageState();
}
class _LoginPageState extends State<LoginPage> {
bool hidePassword = true;
bool isApiCallProcess = false;
GlobalKey<FormState> globalFormKey = GlobalKey<FormState>();
LoginRequestModel loginRequestModel;
final scaffoldKey = GlobalKey<ScaffoldState>();
#override
void initState() {
super.initState();
loginRequestModel = new LoginRequestModel();
}
#override
Widget build(BuildContext context) {
return ProgressHUD(
child: _uiSetup(context),
inAsyncCall: isApiCallProcess,
opacity: 0.3,
);
}
Widget _uiSetup(BuildContext context) {
return Scaffold(
key: scaffoldKey,
backgroundColor: Theme.of(context).accentColor,
body: SingleChildScrollView(
child: Column(
children: <Widget>[
Stack(
children: <Widget>[
Container(
width: double.infinity,
padding: EdgeInsets.symmetric(vertical: 30, horizontal: 20),
margin: EdgeInsets.symmetric(vertical: 85, horizontal: 20),
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(20),
color: Theme.of(context).primaryColor,
boxShadow: [
BoxShadow(
color: Theme.of(context).hintColor.withOpacity(0.2),
offset: Offset(0, 10),
blurRadius: 20)
],
),
child: Form(
key: globalFormKey,
child: Column(
children: <Widget>[
SizedBox(height: 25),
Text(
"Login",
style: Theme.of(context).textTheme.headline2,
),
SizedBox(height: 20),
new TextFormField(
keyboardType: TextInputType.emailAddress,
onSaved: (input) => loginRequestModel.email = input,
validator: (input) => !input.contains('#')
? "Email Id should be valid"
: null,
decoration: new InputDecoration(
hintText: "Email Address",
enabledBorder: UnderlineInputBorder(
borderSide: BorderSide(
color: Theme.of(context)
.accentColor
.withOpacity(0.2))),
focusedBorder: UnderlineInputBorder(
borderSide: BorderSide(
color: Theme.of(context).accentColor)),
prefixIcon: Icon(
Icons.email,
color: Theme.of(context).accentColor,
),
),
),
SizedBox(height: 20),
new TextFormField(
style:
TextStyle(color: Theme.of(context).accentColor),
keyboardType: TextInputType.text,
onSaved: (input) =>
loginRequestModel.password = input,
validator: (input) => input.length < 3
? "Password should be more than 3 characters"
: null,
obscureText: hidePassword,
decoration: new InputDecoration(
hintText: "Password",
enabledBorder: UnderlineInputBorder(
borderSide: BorderSide(
color: Theme.of(context)
.accentColor
.withOpacity(0.2))),
focusedBorder: UnderlineInputBorder(
borderSide: BorderSide(
color: Theme.of(context).accentColor)),
prefixIcon: Icon(
Icons.lock,
color: Theme.of(context).accentColor,
),
suffixIcon: IconButton(
onPressed: () {
setState(() {
hidePassword = !hidePassword;
});
},
color: Theme.of(context)
.accentColor
.withOpacity(0.4),
icon: Icon(hidePassword
? Icons.visibility_off
: Icons.visibility),
),
),
),
SizedBox(height: 30),
FlatButton(
padding: EdgeInsets.symmetric(
vertical: 12, horizontal: 80),
onPressed: () {
if (validateAndSave()) {
print(loginRequestModel.toJson());
setState(() {
isApiCallProcess = true;
});
APIService apiService = new APIService();
apiService.login(loginRequestModel).then((value) {
if (value != null) {
setState(() {
isApiCallProcess = false;
});
if (value.token.isNotEmpty) {
final snackBar = SnackBar(
content: Text("Login Successful"));
scaffoldKey.currentState
.showSnackBar(snackBar);
} else {
final snackBar =
SnackBar(content: Text(value.error));
scaffoldKey.currentState
.showSnackBar(snackBar);
}
}
});
}
},
child: Text(
"Login",
style: TextStyle(color: Colors.white),
),
color: Theme.of(context).accentColor,
shape: StadiumBorder(),
),
SizedBox(height: 15),
],
),
),
),
],
),
],
),
),
);
}
bool validateAndSave() {
final form = globalFormKey.currentState;
if (form.validate()) {
form.save();
return true;
}
return false;
}
}
can friends help me to overcome these obstacles?

Answer 1

I suggest you to use print and see your data result from api-call..
import 'package:http/http.dart' as http;
import 'dart:convert';
import '../model/login_model.dart';
class APIService {
Future<LoginResponseModel> login(LoginRequestModel requestModel) async {
String url = "http://192.168.100.211:8080/login";
final response = await http.post(url, body: requestModel.toJson());
print (response)
if (response.statusCode == 200 || response.statusCode == 400) {
return LoginResponseModel.fromJson(
json.decode(response.body),
);
} else {
throw Exception('Failed to load data!');
}
}
}