Myujth

I´m create a simple login in flutter. This login connect to a API. For do this I retrieve inputs value and send to a method, but return

type '_InternalLinkedHashMap' is not a subtype of type 'Map'

This is my model

class Login 
 final String usuario, password;

 Login(this.usuario, this.password);

 factory Login.fromJson(Map<String, dynamic> json) 
 return Login(
 usuario: json['usuario'] as String,
 password: json['password'] as String,
 );
 

And this is my main class

import 'package:flutter/material.dart';
import 'package:igota/screens/home/home_page.dart';
import 'package:igota/model/login.dart';
import 'dart:async';
import 'dart:convert';
import 'package:http/http.dart' as http;

class LoginPage extends StatefulWidget 
 static String tag = 'login-page';
 @override
 _LoginPageState createState() => new _LoginPageState();


class _LoginPageState extends State<LoginPage> 
 final _formKey = GlobalKey<FormState>();
 final userValue = new TextEditingController();
 final passwordValue = new TextEditingController();

 @override
 Widget build(BuildContext context) 
 final logo = Hero(
 tag: 'hero',
 child: CircleAvatar(
 backgroundColor: Colors.transparent,
 radius: 48.0,
 child: Image.asset('assets/logo.png'),
 ),
 );

 final username = TextFormField(
 controller: userValue,
 validator: (value) 
 if (value.isEmpty) 
 return 'Introduce un nombre';
 
 ,
 keyboardType: TextInputType.emailAddress,
 autofocus: false,
 decoration: InputDecoration(
 hintText: 'Usuario',
 contentPadding: EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
 border: OutlineInputBorder(borderRadius: BorderRadius.circular(32.0)),
 ),
 );

 final password = TextFormField(
 controller: passwordValue,
 validator: (value) 
 if (value.isEmpty) 
 return 'Introduce una contraseña';
 
 ,
 autofocus: false,
 obscureText: true,
 decoration: InputDecoration(
 hintText: 'Contraseña',
 contentPadding: EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
 border: OutlineInputBorder(borderRadius: BorderRadius.circular(32.0)),
 ),
 );

 Widget _buildLoginButton(BuildContext context) 
 return Padding(
 padding: EdgeInsets.symmetric(vertical: 16.0),
 child: Material(
 borderRadius: BorderRadius.circular(30.0),
 child: MaterialButton(
 minWidth: 200.0,
 height: 42.0,
 onPressed: () 
 fetchPost(userValue, passwordValue);
 //final snackBar = SnackBar(
 // content: Text(
 // 'Usuario/Contraseña incorrecto',
 // textAlign: TextAlign.center,
 //));
 //Scaffold.of(context).showSnackBar(snackBar);
 if (_formKey.currentState.validate()) 
 Navigator.of(context).pushNamed(HomePage.tag);
 
 ,
 color: Colors.blue[300],
 child: Text('Entrar', style: TextStyle(color: Colors.white)),
 ),
 ),
 );
 

 final forgotLabel = FlatButton(
 child: Text(
 '¿Contraseña olvidada?',
 style: TextStyle(color: Colors.black54),
 ),
 onPressed: () ,
 );

 return Scaffold(
 backgroundColor: Colors.white,
 body: Builder(
 builder: (context) => Center(
 child: Form(
 key: _formKey,
 child: ListView(
 shrinkWrap: true,
 padding: EdgeInsets.only(left: 24.0, right: 24.0),
 children: <Widget>[
 logo,
 SizedBox(height: 48.0),
 username,
 SizedBox(height: 8.0),
 password,
 SizedBox(height: 24.0),
 _buildLoginButton(context),
 forgotLabel
 ],
 ),
 )),
 ),
 );
 


//Test
Future<Login> fetchPost(user, pass) async 
 Map headers = 
 'Content-type': 'application/json',
 'Accept': 'application/json',
 ;
 final response = await http.post(
 'URL',
 body: "usuario": user.text, "password": pass.text,
 headers: headers);
 final responseJson = json.decode(response.body);
 return Login.fromJson(responseJson);

So i need to return response and check if correct or incorrect to show snackbar. I don't know exactly what i'm doing right or wrong :$

You need to define the type of headers like this:

Map<String, String> headers = 
 'Content-type': 'application/json',
 'Accept': 'application/json',
;

EDIT: You need to use json.encode on the body of a request with 'Content-type': 'application/json' as well.

EDIT2:

Future<Login> fetchPost(user, pass) async 
 Map<String, String> headers = 
 'Content-type': 'application/json',
 'Accept': 'application/json',
 ;
 final response = await http.post(
 'URL',
 body: json.encode("usuario": user.text, "password": pass.text),
 headers: headers);
 final responseJson = json.decode(response.body);
 return Login.fromJson(responseJson);