我正在尝试使用以下方式在路线之间传递值Navigator.pushReplacementNamed()
,但我不明白。
我无法弄清楚数据退出的正确语法和逻辑是什么pushReplacementNamed
并得到routes
key.
你能帮助我吗?
输入以下代码以方便理解:
import 'package:flutter/material.dart';
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new MaterialApp(
theme: new ThemeData(
primarySwatch: Colors.blue,
),
home: new MyHomePage(),
routes: <String, WidgetBuilder> {
'/form': (BuildContext context) => new FormPage(email: ???, header: {'auth': ???}),
},
);
}
}
class MyHomePage extends StatefulWidget {
@override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
@override
Widget build(BuildContext context) {
return new Scaffold(
floatingActionButton: new FloatingActionButton(
onPressed: () {
Navigator.pushReplacementNamed(context, '/form', {email: '[email protected] /cdn-cgi/l/email-protection', header: {'auth': '1234'}});
},
child: new Icon(Icons.navigate_next),
),
);
}
}
class FormPage extends StatefulWidget {
FormPage({Key key, this.email, this.header}) : super(key: key);
String email;
Map header;
@override
FormPageState createState() => new FormPageState();
}
class FormPageState extends State<FormPage> {
@override
Widget build(BuildContext context) {
return new Container(
child: new Column(
children: <Widget>[
new Text(widget.email),
new Text(widget.header['auth'])
],
),
);
}
}
修正后:
尝试使用的目的pushReplacementNamed
目的是删除路线历史记录,因此,如果用户按设备的后退按钮返回到之前的路线,则该路线将不再存在。参考 https://stackoverflow.com/questions/44978216/flutter-remove-back-button-on-appbar
此实现的原因是要在登录页面上使用,如果用户已经通过了身份验证google sign
他被重定向到传递登录参数的下一页,并且无法通过设备的后退按钮返回到登录页面。
import 'package:flutter/material.dart';
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new MaterialApp(
theme: new ThemeData(
primarySwatch: Colors.blue,
),
home: new MyHomePage(),
routes: <String, WidgetBuilder> {
'/form': (BuildContext context) => new FormPage(), //new
},
);
}
}
class MyHomePage extends StatefulWidget {
@override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
@override
Widget build(BuildContext context) {
return new Scaffold(
floatingActionButton: new FloatingActionButton(
onPressed: () {
Navigator.of(context).pushReplacement( //new
new MaterialPageRoute( //new
settings: const RouteSettings(name: '/form'), //new
builder: (context) => new FormPage(email: '[email protected] /cdn-cgi/l/email-protection', header: {'auth': '1234'}) //new
) //new
); //new
},
child: new Icon(Icons.navigate_next),
),
);
}
}
class FormPage extends StatefulWidget {
FormPage({Key key, this.email, this.header}) : super(key: key);
String email;
Map header;
@override
FormPageState createState() => new FormPageState();
}
class FormPageState extends State<FormPage> {
@override
Widget build(BuildContext context) {
return new Container(
child: new Column(
children: <Widget>[
new Text(widget.email),
new Text(widget.header['auth'])
],
),
);
}
}