每次尝试输入TextField或按“您已经有一个帐户？”从注册页面移至登录页面时，我都会得到Incorrect use of ParentDataWidget。按钮。
这是我用于用户界面的代码
import 'package:flutter/material.dart';
import 'package:tariffo/HomePage.dart';
import 'auth.dart';
import 'LoginPage.dart';
import 'LoginScreen.dart';
import 'package:firebase_auth/firebase_auth.dart';
class SignupPage extends StatefulWidget {
@override
_SignupPageState createState() => _SignupPageState();
}
class _SignupPageState extends State<SignupPage> {
final _formKey = GlobalKey<FormState>();
String email = '';
String password = '';
String error = '';
bool loading = false;
final Authentication authentication = Authentication();
@override
Widget build(BuildContext context) {
Widget _backButton() {
return InkWell(
onTap: () {
Navigator.pop(context);
},
child: Container(
padding: EdgeInsets.symmetric(horizontal: 10),
child: Row(
children: <Widget>[
Container(
padding: EdgeInsets.only(left: 0, top: 10, bottom: 10),
child: Icon(Icons.keyboard_arrow_left, color: Colors.black),
),
Text('Back',
style: TextStyle(fontSize: 12, fontWeight: FontWeight.w500))
],
),
),
);
}
return loading
? Homepage()
: Scaffold(
resizeToAvoidBottomInset: false,
resizeToAvoidBottomPadding: false,
body: Container(
height: 900.0,
width: 500.0,
child: Column(
children: <Widget>[
Padding(
padding: const EdgeInsets.only(top: 50.0),
child: Row(
children: <Widget>[
IconButton(
icon: Icon(Icons.arrow_back_ios, color: Colors.white),
onPressed: () {
Navigator.pushReplacement(
context,
MaterialPageRoute(
builder: (context) => LoginScreen()));
},
)
],
),
),
Positioned(top: 40, left: 0, child: _backButton()),
Padding(
padding: const EdgeInsets.only(top: 40.0),
child: RichText(
text: TextSpan(
text: 'Tariffo',
style: TextStyle(
color: Colors.blue,
fontFamily: 'SignPainter',
fontSize: 60),
),
),
),
SizedBox(
height: 400.0,
child: Form(
key: _formKey,
child: Column(
children: <Widget>[
Padding(
padding: const EdgeInsets.only(
left: 80.0, right: 80.0, top: 40.0),
child: TextFormField(
validator: (val) =>
val.isEmpty ? 'enter email' : null,
onChanged: (val) {
setState(() => email = val);
},
style: TextStyle(color: Colors.black),
decoration: InputDecoration(
hintText: 'enter email',
hintStyle: TextStyle(
fontFamily: 'Antra',
fontSize: 12.0,
color: Colors.black)),
),
),
Padding(
padding: const EdgeInsets.only(
left: 80.0, right: 80.0, top: 40.0),
child: TextFormField(
validator: (val) => val.length < 8
? 'enter password > 8 digits'
: null,
onChanged: (val) {
setState(() => password = val);
},
style: TextStyle(color: Colors.black),
decoration: InputDecoration(
hintText: 'enter password',
hintStyle: TextStyle(
fontFamily: 'Antra',
fontSize: 12.0,
color: Colors.black)),
obscureText: true,
),
),
SizedBox(height: 50),
Padding(
padding: const EdgeInsets.only(top: 40.0),
child: MaterialButton(
color: Colors.blue,
onPressed: () async {
if (_formKey.currentState.validate()) {
setState(() => loading = true);
dynamic result = await authentication
.registerwithEmailAndPassword(
email, password);
if (result == null) {
setState(() => error =
'Sorry,These credentials will not work out');
loading = false;
}
}
},
child: Text(
'Sign up',
style: TextStyle(
fontFamily: 'Antra', color: Colors.white),
),
),
),
],
),
)),
_createAccountLabel(),
],
),
),
);
}
Widget _createAccountLabel() {
return InkWell(
onTap: () {
Navigator.push(
context, MaterialPageRoute(builder: (context) => LoginPage()));
},
child: Container(
margin: EdgeInsets.symmetric(vertical: 20),
padding: EdgeInsets.all(15),
alignment: Alignment.bottomCenter,
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'Do you have an account ?',
style: TextStyle(fontSize: 13, fontWeight: FontWeight.w600),
),
SizedBox(
width: 10,
),
Text(
'Login',
style: TextStyle(
color: Colors.blue,
fontSize: 13,
fontWeight: FontWeight.w600),
),
],
),
),
);
}
}
import 'package:flutter/material.dart';
import 'SignUp.dart';
import 'brazierContainer.dart';
import 'package:google_fonts/google_fonts.dart';
import 'LoginScreen.dart';
import 'HomePage.dart';
import 'auth.dart';
class LoginPage extends StatefulWidget {
LoginPage({Key key, this.title}) : super(key: key);
final String title;
@override
_LoginPageState createState() => _LoginPageState();
}
class _LoginPageState extends State<LoginPage> {
final _formKey = GlobalKey<FormState>();
String email = '';
String password = '';
String error = '';
bool loading = false;
final Authentication authentication = Authentication();
@override
Widget build(BuildContext context) {
Widget _backButton() {
return InkWell(
onTap: () {
Navigator.pop(context);
},
child: Container(
padding: EdgeInsets.symmetric(horizontal: 10),
child: Row(
children: <Widget>[
Container(
padding: EdgeInsets.only(left: 0, top: 10, bottom: 10),
child: Icon(Icons.keyboard_arrow_left, color: Colors.black),
),
Text('Back',
style: TextStyle(fontSize: 12, fontWeight: FontWeight.w500))
],
),
),
);
}
return loading
? Homepage()
: Scaffold(
resizeToAvoidBottomInset: false,
resizeToAvoidBottomPadding: false,
body: Container(
height: 900.0,
width: 500.0,
child: Column(
children: <Widget>[
Padding(
padding: const EdgeInsets.only(top: 50.0),
child: Row(
children: <Widget>[
IconButton(
icon: Icon(Icons.arrow_back_ios, color: Colors.white),
onPressed: () {
Navigator.pushReplacement(
context,
MaterialPageRoute(
builder: (context) => LoginScreen()));
},
)
],
),
),
Positioned(top: 40, left: 0, child: _backButton()),
Padding(
padding: const EdgeInsets.only(top: 40.0),
child: RichText(
text: TextSpan(
text: 'Tariffo',
style: TextStyle(
color: Colors.blue,
fontFamily: 'SignPainter',
fontSize: 60),
),
),
),
SizedBox(
height: 400.0,
child: Form(
key: _formKey,
child: Column(
children: <Widget>[
Padding(
padding: const EdgeInsets.only(
left: 80.0, right: 80.0, top: 40.0),
child: TextFormField(
validator: (val) =>
val.isEmpty ? 'enter email' : null,
onChanged: (val) {
setState(() => email = val);
},
style: TextStyle(color: Colors.black),
decoration: InputDecoration(
hintText: 'enter email',
hintStyle: TextStyle(
fontFamily: 'Antra',
fontSize: 12.0,
color: Colors.black)),
),
),
Padding(
padding: const EdgeInsets.only(
left: 80.0, right: 80.0, top: 40.0),
child: TextFormField(
validator: (val) => val.length < 8
? 'enter password > 8 digits'
: null,
onChanged: (val) {
setState(() => password = val);
},
style: TextStyle(color: Colors.black),
decoration: InputDecoration(
hintText: 'enter password',
hintStyle: TextStyle(
fontFamily: 'Antra',
fontSize: 12.0,
color: Colors.black)),
obscureText: true,
),
),
SizedBox(height: 50),
Padding(
padding: const EdgeInsets.only(top: 40.0),
child: MaterialButton(
color: Colors.blue,
onPressed: () async {
if (_formKey.currentState.validate()) {
setState(() => loading = true);
dynamic result = await authentication
.signUpWithEmailAndPassword(
email, password);
if (result == null) {
setState(() => error =
'Sorry,These credentials will not work out');
loading = false;
}
}
},
child: Text(
'Sign in',
style: TextStyle(
fontFamily: 'Antra', color: Colors.white),
),
),
),
Container(
padding: EdgeInsets.symmetric(vertical: 10),
alignment: Alignment.centerRight,
child: Text('Forgot Password ?',
style: TextStyle(
fontSize: 14,
fontWeight: FontWeight.w500)),
),
],
),
)),
_createAccountLabel(),
],
),
),
);
}
Widget _createAccountLabel() {
return InkWell(
onTap: () {
Navigator.push(
context, MaterialPageRoute(builder: (context) => SignupPage()));
},
child: Container(
margin: EdgeInsets.symmetric(vertical: 20),
padding: EdgeInsets.all(15),
alignment: Alignment.bottomCenter,
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'Don/t you have an account ?',
style: TextStyle(fontSize: 13, fontWeight: FontWeight.w600),
),
SizedBox(
width: 10,
),
Text(
'Register',
style: TextStyle(
color: Colors.blue,
fontSize: 13,
fontWeight: FontWeight.w600),
),
],
),
),
);
}
}
这是错误：
════════ Exception caught by widgets library ═══════════════════════════════════
Incorrect use of ParentDataWidget.
════════════════════════════════════════════════════════════════════════════════
════════ Exception caught by widgets library ═══════════════════════════════════
The following assertion was thrown while applying parent data.:
Incorrect use of ParentDataWidget.
The ParentDataWidget Positioned(left: 0.0, top: 40.0) wants to apply ParentData of type StackParentData to a RenderObject, which has been set up to accept ParentData of incompatible type FlexParentData.
Usually, this means that the Positioned widget has the wrong ancestor RenderObjectWidget. Typically, Positioned widgets are placed directly inside Stack widgets.
The offending Positioned is currently placed inside a Column widget.
答案 0 :(得分：0)
您在Positioned中使用Column。 Positioned仅可在Stack中使用。因此，请考虑将Column替换为Stack或使用Alignment(x,y)使其对齐