Example 1
import 'package:dart_printf/dart_printf.dart';
import 'package:flutter/material.dart';
class Book {
final String title;
final String author;
Book(this.title, this.author);
}
List<Book> books = [
Book('Stranger in a Strange Land', 'Robert A. Heinlein'),
Book('Foundation', 'Isaac Asimov'),
Book('Fahrenheit 451', 'Ray Bradbury'),
];
void main() => runApp(MyApp());
class MyApp extends StatefulWidget {
@override
State<StatefulWidget> createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
Book _selectedBook;
@override
Widget build(BuildContext context) {
return MaterialApp(
home: Navigator(
pages: [
MaterialPage(
child: BooksPage(books: books, onTapped: _handleBookTapped),
),
if (_selectedBook != null) BookDetailsPage(book: _selectedBook)
],
onPopPage: (route, result) {
printf("page result: %o", result);
if (!route.didPop(result)) {
return false;
}
// 通过将_selectedBook设置为null来更新页面列表
setState(() {
_selectedBook = null;
});
return true;
},
),
);
}
void _handleBookTapped(Book book) {
setState(() {
_selectedBook = book;
});
}
}
class BookDetailsPage extends Page {
final Book book;
BookDetailsPage({
this.book,
}) : super(key: ValueKey(book));
Route createRoute(BuildContext context) {
return MaterialPageRoute(
settings: this,
builder: (BuildContext context) {
return BookPage(book: book);
},
);
}
}
class BooksPage extends StatelessWidget {
final List<Book> books;
final ValueChanged<Book> onTapped;
BooksPage({
@required this.books,
@required this.onTapped,
});
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text('books')),
body: ListView(
children: [
for (var book in books)
ListTile(
title: Text(book.title),
subtitle: Text(book.author),
onTap: () => onTapped(book),
)
],
),
);
}
}
class BookPage extends StatelessWidget {
final Book book;
BookPage({@required this.book});
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text(book.title)),
body: Padding(
padding: const EdgeInsets.all(8.0),
child: Center(
child: Column(
children: [
Text(book.author),
RaisedButton(
onPressed: () => Navigator.of(context).pop(book.title),
child: Text('Pop'),
),
],
),
),
),
);
}
}
Example 2
import 'package:dart_printf/dart_printf.dart';
import 'package:flutter/material.dart';
class Book {
final String title;
final String author;
Book(this.title, this.author);
}
List<Book> books = [
Book('Stranger in a Strange Land', 'Robert A. Heinlein'),
Book('Foundation', 'Isaac Asimov'),
Book('Fahrenheit 451', 'Ray Bradbury'),
];
void main() => runApp(MyApp());
class MyApp extends StatefulWidget {
@override
State<StatefulWidget> createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
BookRouterDelegate _routerDelegate = BookRouterDelegate();
BookRouteInformationParser _routeInformationParser =
BookRouteInformationParser();
@override
Widget build(BuildContext context) {
return MaterialApp.router(
routerDelegate: _routerDelegate,
routeInformationParser: _routeInformationParser,
);
}
}
class BookRouteInformationParser extends RouteInformationParser<BookRoutePath> {
/// 通常在web程序中手动更改url是会收到通知
@override
Future<BookRoutePath> parseRouteInformation(RouteInformation routeInformation) async {
printf('localtion: %s', routeInformation.location);
final uri = Uri.parse(routeInformation.location);
// Handle '/'
if (uri.pathSegments.length == 0) {
return BookRoutePath.home();
}
// Handle '/book/:id'
if (uri.pathSegments.length == 2) {
if (uri.pathSegments[0] != 'book') return BookRoutePath.unknown();
var remaining = uri.pathSegments[1];
var id = int.tryParse(remaining);
if (id == null) return BookRoutePath.unknown();
return BookRoutePath.details(id);
}
// Handle unknown routes
return BookRoutePath.unknown();
}
@override
RouteInformation restoreRouteInformation(BookRoutePath path) {
if (path.isUnknown) {
return RouteInformation(location: '/404');
}
if (path.isHomePage) {
return RouteInformation(location: '/');
}
if (path.isDetailsPage) {
return RouteInformation(location: '/book/${path.id}');
}
return null;
}
}
class BookRouterDelegate extends RouterDelegate<BookRoutePath>
with ChangeNotifier, PopNavigatorRouterDelegateMixin<BookRoutePath> {
final GlobalKey<NavigatorState> navigatorKey;
Book _selectedBook;
bool show404 = false;
BookRouterDelegate() : navigatorKey = GlobalKey<NavigatorState>();
BookRoutePath get currentConfiguration {
if (show404) {
return BookRoutePath.unknown();
}
return _selectedBook == null
? BookRoutePath.home()
: BookRoutePath.details(books.indexOf(_selectedBook));
}
@override
Widget build(BuildContext context) {
return Navigator(
key: navigatorKey,
pages: [
MaterialPage(
key: ValueKey('BooksListPage'),
child: BooksPage(books: books, onTapped: _handleBookTapped),
),
if (show404)
MaterialPage(key: ValueKey('UnknownPage'), child: UnknownScreen())
else if (_selectedBook != null)
BookDetailsPage(book: _selectedBook)
],
onPopPage: (route, result) {
printf("[page result] %o", result);
if (!route.didPop(result)) {
return false;
}
// 通过将_selectedBook设置为null来更新页面列表
_selectedBook = null;
show404 = false;
notifyListeners();
return true;
},
);
}
@override
Future<void> setNewRoutePath(BookRoutePath path) async {
printf('path id: %o', path.id);
if (path.isUnknown) {
_selectedBook = null;
show404 = true;
return;
}
if (path.isDetailsPage) {
if (path.id < 0 || path.id > books.length - 1) {
show404 = true;
return;
}
_selectedBook = books[path.id];
} else {
_selectedBook = null;
}
show404 = false;
}
void _handleBookTapped(Book book) {
_selectedBook = book;
notifyListeners();
}
}
class BookDetailsPage extends Page {
final Book book;
BookDetailsPage({
this.book,
}) : super(key: ValueKey(book));
Route createRoute(BuildContext context) {
return MaterialPageRoute(
settings: this,
builder: (BuildContext context) {
return BookPage(book: book);
},
);
}
}
class BookRoutePath {
final int id;
final bool isUnknown;
BookRoutePath.home()
: id = null,
isUnknown = false;
BookRoutePath.details(this.id) : isUnknown = false;
BookRoutePath.unknown()
: id = null,
isUnknown = true;
bool get isHomePage => id == null;
bool get isDetailsPage => id != null;
}
class BooksPage extends StatelessWidget {
final List<Book> books;
final ValueChanged<Book> onTapped;
BooksPage({
@required this.books,
@required this.onTapped,
});
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text('books')),
body: ListView(
children: [
for (var book in books)
ListTile(
title: Text(book.title),
subtitle: Text(book.author),
onTap: () => onTapped(book),
)
],
),
);
}
}
class BookPage extends StatelessWidget {
final Book book;
BookPage({@required this.book});
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text(book.title)),
body: Padding(
padding: const EdgeInsets.all(8.0),
child: Center(
child: Column(
children: [
Text(book.author),
RaisedButton(
onPressed: () => Navigator.of(context).pop(book.title),
child: Text('Pop'),
),
],
),
),
),
);
}
}
class UnknownScreen extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text('404')),
body: Center(
child: Text('404!'),
),
);
}
}
See also: