App crashing and not fetching data Flutter - flutter

Question

import 'dart:convert';
import 'dart:io';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'dart:developer' as devtools;
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: BlocProvider(
create: (context) => PersonsBloc(),
child: const MyHomePage(),
),
);
}
}
#immutable
abstract class LoadAction {
const LoadAction();
}
#immutable
class LoadPersonsAction implements LoadAction {
final PersonsUrl url;
const LoadPersonsAction({required this.url}) : super();
}
enum PersonsUrl {
persons1,
persons2,
}
extension Subscript<T> on Iterable<T> {
T? operator [](int index) => length > index ? elementAt(index) : null;
}
extension UrlString on PersonsUrl {
String get getUrl {
switch (this) {
case PersonsUrl.persons1:
devtools.log("Getting person1 url");
return "http://127.0.0.1:5500/app_2/api/persons1.json";
case PersonsUrl.persons2:
devtools.log("Getting person2 url");
return "http://127.0.0.1:5500/app_2/api/persons2.json";
}
}
}
#immutable
class Person {
final String name;
final int age;
const Person({required this.name, required this.age});
Person.fromJson(Map<String, dynamic> json)
: name = json['name'] as String,
age = json['age'] as int;
}
Future<Iterable<Person>> getPersons(String url) => HttpClient()
.getUrl(Uri.parse(url))
.then((req) => req.close())
.then((resp) => resp.transform(utf8.decoder).join())
.then((str) => json.decode(str) as List<dynamic>)
.then((value) => value.map((e) => Person.fromJson(e)));
#immutable
class FetchResult {
final Iterable<Person> persons;
final bool isRetrievedFromCache;
const FetchResult(
{required this.persons, required this.isRetrievedFromCache});
#override
String toString() =>
'FetchResult (isRetrievedFromCache = $isRetrievedFromCache, persons = $persons';
}
class PersonsBloc extends Bloc<LoadAction, FetchResult?> {
final Map<PersonsUrl, Iterable<Person>> _cache = {};
PersonsBloc() : super(null) {
on<LoadPersonsAction>((event, emit) async {
final url = event.url;
devtools.log("In bloc :$url");
if (_cache.containsKey(url)) {
devtools.log("Present in cache");
final cachedPersons = _cache[url]!;
final result = FetchResult(
persons: cachedPersons,
isRetrievedFromCache: true,
);
emit(result);
} else {
devtools.log("Not present in cache");
final persons = await getPersons(url.getUrl);
if (persons.isNotEmpty) {
print("Persons is there");
} else {
print("Persons is not there");
}
_cache[url] = persons;
final result =
FetchResult(persons: persons, isRetrievedFromCache: false);
emit(result);
}
});
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({
Key? key,
}) : super(key: key);
#override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('BLoC App 2'),
),
body: Column(
children: [
Row(
children: [
TextButton(
onPressed: () {
devtools.log("Clicked to get person1");
context.read<PersonsBloc>().add(
const LoadPersonsAction(url: PersonsUrl.persons1));
},
child: const Text('Load Json #1')),
TextButton(
onPressed: () {
devtools.log("Clicked to get person2");
context.read<PersonsBloc>().add(
const LoadPersonsAction(url: PersonsUrl.persons2));
},
child: const Text('Load Json #2')),
],
),
BlocBuilder<PersonsBloc, FetchResult?>(
buildWhen: ((previous, current) {
return previous?.persons != current?.persons;
}),
builder: ((context, state) {
final persons = state?.persons;
if (persons == null) {
return const SizedBox();
}
return ListView.builder(
itemCount: persons.length,
itemBuilder: ((context, index) {
devtools.log('rendering list tiles');
final person = persons[index]!;
return ListTile(
leading: Text(person.age.toString()),
title: Text(person.name),
);
}));
}),
)
],
));
}
}
I am learning BLoC State Management from Vandad Nahavandipoor's State Management Playlist, when I click on the Load Json #1 button, it goes until the getPersons() function is called, but then doesn't fetch any data to return. Instead, it shows me some errors with no description whatsoever.
ERROR:
enter image description here
Here is the error I get after I Hot Restart:
E/flutter ( 2894): [ERROR:flutter/lib/ui/ui_dart_state.cc(198)] Unhandled Exception: SocketException: Connection timed out (OS Error:
Connection timed out, errno = 110), address = 192.168.0.1, port =
51180