blob: 2a87a83cdce56574e027b1d4ba2bd78c7a5bfaa3 [file] [log] [blame]
// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// ignore_for_file: use_late_for_private_fields_and_variables
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';
import 'shared/data.dart';
void main() => runApp(App());
/// The main app.
class App extends StatelessWidget {
/// Creates a [App].
App({Key? key}) : super(key: key);
/// The title of the app.
static const String title = 'GoRouter Example: Async Data';
/// Repository to query data from.
static final Repository repo = Repository();
@override
Widget build(BuildContext context) => MaterialApp.router(
routeInformationParser: _router.routeInformationParser,
routerDelegate: _router.routerDelegate,
title: title,
);
late final GoRouter _router = GoRouter(
routes: <GoRoute>[
GoRoute(
path: '/',
builder: (BuildContext context, GoRouterState state) =>
const HomeScreen(),
routes: <GoRoute>[
GoRoute(
path: 'family/:fid',
builder: (BuildContext context, GoRouterState state) =>
FamilyScreen(
fid: state.params['fid']!,
),
routes: <GoRoute>[
GoRoute(
path: 'person/:pid',
builder: (BuildContext context, GoRouterState state) =>
PersonScreen(
fid: state.params['fid']!,
pid: state.params['pid']!,
),
),
],
),
],
),
],
);
}
/// The home screen.
class HomeScreen extends StatefulWidget {
/// Creates a [HomeScreen].
const HomeScreen({Key? key}) : super(key: key);
@override
State<HomeScreen> createState() => _HomeScreenState();
}
class _HomeScreenState extends State<HomeScreen> {
Future<List<Family>>? _future;
@override
void initState() {
super.initState();
_fetch();
}
@override
void didUpdateWidget(covariant HomeScreen oldWidget) {
super.didUpdateWidget(oldWidget);
// refresh cached data
_fetch();
}
void _fetch() => _future = App.repo.getFamilies();
@override
Widget build(BuildContext context) => FutureBuilder<List<Family>>(
future: _future,
builder: (BuildContext context, AsyncSnapshot<List<Family>> snapshot) {
if (snapshot.connectionState == ConnectionState.waiting) {
return Scaffold(
appBar: AppBar(title: const Text('${App.title}: Loading...')),
body: const Center(child: CircularProgressIndicator()),
);
}
if (snapshot.hasError) {
return Scaffold(
appBar: AppBar(title: const Text('${App.title}: Error')),
body: SnapshotError(snapshot.error!),
);
}
assert(snapshot.hasData);
final List<Family> families = snapshot.data!;
return Scaffold(
appBar: AppBar(
title: Text('${App.title}: ${families.length} families'),
),
body: ListView(
children: <Widget>[
for (final Family f in families)
ListTile(
title: Text(f.name),
onTap: () => context.go('/family/${f.id}'),
)
],
),
);
},
);
}
/// The family screen.
class FamilyScreen extends StatefulWidget {
/// Creates a [FamilyScreen].
const FamilyScreen({required this.fid, Key? key}) : super(key: key);
/// The id of the family.
final String fid;
@override
State<FamilyScreen> createState() => _FamilyScreenState();
}
class _FamilyScreenState extends State<FamilyScreen> {
Future<Family>? _future;
@override
void initState() {
super.initState();
_fetch();
}
@override
void didUpdateWidget(covariant FamilyScreen oldWidget) {
super.didUpdateWidget(oldWidget);
// refresh cached data
if (oldWidget.fid != widget.fid) {
_fetch();
}
}
void _fetch() => _future = App.repo.getFamily(widget.fid);
@override
Widget build(BuildContext context) => FutureBuilder<Family>(
future: _future,
builder: (BuildContext context, AsyncSnapshot<Family> snapshot) {
if (snapshot.connectionState == ConnectionState.waiting) {
return Scaffold(
appBar: AppBar(title: const Text('Loading...')),
body: const Center(child: CircularProgressIndicator()),
);
}
if (snapshot.hasError) {
return Scaffold(
appBar: AppBar(title: const Text('Error')),
body: SnapshotError(snapshot.error!),
);
}
assert(snapshot.hasData);
final Family family = snapshot.data!;
return Scaffold(
appBar: AppBar(title: Text(family.name)),
body: ListView(
children: <Widget>[
for (final Person p in family.people)
ListTile(
title: Text(p.name),
onTap: () => context.go(
'/family/${family.id}/person/${p.id}',
),
),
],
),
);
},
);
}
/// The person screen.
class PersonScreen extends StatefulWidget {
/// Creates a [PersonScreen].
const PersonScreen({required this.fid, required this.pid, Key? key})
: super(key: key);
/// The id of family the person is in.
final String fid;
/// The id of the person.
final String pid;
@override
State<PersonScreen> createState() => _PersonScreenState();
}
class _PersonScreenState extends State<PersonScreen> {
Future<FamilyPerson>? _future;
@override
void initState() {
super.initState();
_fetch();
}
@override
void didUpdateWidget(covariant PersonScreen oldWidget) {
super.didUpdateWidget(oldWidget);
// refresh cached data
if (oldWidget.fid != widget.fid || oldWidget.pid != widget.pid) {
_fetch();
}
}
void _fetch() => _future = App.repo.getPerson(widget.fid, widget.pid);
@override
Widget build(BuildContext context) => FutureBuilder<FamilyPerson>(
future: _future,
builder: (BuildContext context, AsyncSnapshot<FamilyPerson> snapshot) {
if (snapshot.connectionState == ConnectionState.waiting) {
return Scaffold(
appBar: AppBar(title: const Text('Loading...')),
body: const Center(child: CircularProgressIndicator()),
);
}
if (snapshot.hasError) {
return Scaffold(
appBar: AppBar(title: const Text('Error')),
body: SnapshotError(snapshot.error!),
);
}
assert(snapshot.hasData);
final FamilyPerson famper = snapshot.data!;
return Scaffold(
appBar: AppBar(title: Text(famper.person.name)),
body: Text(
'${famper.person.name} ${famper.family.name} is '
'${famper.person.age} years old',
),
);
},
);
}
/// The Error page.
class SnapshotError extends StatelessWidget {
/// Creates an error page.
SnapshotError(Object error, {Key? key})
: error = error is Exception ? error : Exception(error),
super(key: key);
/// The error.
final Exception error;
@override
Widget build(BuildContext context) => Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
SelectableText(error.toString()),
TextButton(
onPressed: () => context.go('/'),
child: const Text('Home'),
),
],
),
);
}