我正在建立一个有4-5个表单字段的表单。然而，当我尝试输入数据时，它抛出了以下错误信息
Performing hot reload...
Syncing files to device sdk gphone x86 64...
Reloaded 3 of 512 libraries in 363ms.
W/IInputConnectionWrapper(21437): getTextBeforeCursor on inactive InputConnection
W/IInputConnectionWrapper(21437): getSelectedText on inactive InputConnection
W/IInputConnectionWrapper(21437): getTextAfterCursor on inactive InputConnection
W/IInputConnectionWrapper(21437): beginBatchEdit on inactive InputConnection
W/IInputConnectionWrapper(21437): endBatchEdit on inactive InputConnection
════════ Exception caught by rendering library ═════════════════════════════════════════════════════
The following assertion was thrown during layout:
A RenderFlex overflowed by 192 pixels on the bottom.
The relevant error-causing widget was:
Column file:///C:/Users/xyz/Documents/quizmaker/lib/views/signup.dart:54:20
The overflowing RenderFlex has an orientation of Axis.vertical.
The edge of the RenderFlex that is overflowing has been marked in the rendering with a yellow and black striped pattern. This is usually caused by the contents being too big for the RenderFlex.
Consider applying a flex factor (e.g. using an Expanded widget) to force the children of the RenderFlex to fit within the available space instead of being sized to their natural size.
This is considered an error condition because it indicates that there is content that cannot be seen. If the content is legitimately bigger than the available space, consider clipping it with a ClipRect widget before putting it in the flex, or using a scrollable container rather than a Flex, like a ListView.
The specific RenderFlex in question is: RenderFlex#322a5 relayoutBoundary=up2 OVERFLOWING
... needs compositing
... parentData: offset=Offset(24.0, 0.0) (can use size)
... constraints: BoxConstraints(0.0<=w<=363.4, 0.0<=h<=321.1)
... size: Size(363.4, 321.1)
... direction: vertical
... mainAxisAlignment: start
... mainAxisSize: min
... crossAxisAlignment: start
... textDirection: ltr
... verticalDirection: down
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以下是我的代码
import 'package:flutter/material.dart';
import 'package:quizmaker/services/auth.dart';
import 'package:quizmaker/views/home.dart';
import 'package:quizmaker/views/signin.dart';
import 'package:quizmaker/widgets/widgets.dart';
class SignUp extends StatefulWidget {
@override
_SignUpState createState() => _SignUpState();
}
class _SignUpState extends State<SignUp> {
final _formKey = GlobalKey<FormState>();
String sName, fName, lName, email, phone, password;
AuthService authService = new AuthService();
bool _isLoading = false;
signUp() async {
if(_formKey.currentState.validate()){
setState(() {
_isLoading = true;
});
authService.signUpWithEmailAndPass(email, password).then((value){
if(value != null){
setState(() {
_isLoading = false;
});
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => Home()
));
}
});
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: appBar(context),
centerTitle: true,
backgroundColor: Colors.transparent,
elevation: 0.0,
brightness: Brightness.light,
),
body: _isLoading ? Container(
child: Center(child: CircularProgressIndicator(),),
) : Form(
key: _formKey,
child: Container(
padding: EdgeInsets.symmetric(horizontal: 24),
child: Container(
child: Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Spacer(),
TextFormField(
validator: (val){
return val.isEmpty ? "Enter School Name" : null ;
} ,
decoration: InputDecoration(
hintText: "School Name"
),
onChanged: (val){
sName = val;
},
),
SizedBox(height: 6,),
TextFormField(
validator: (val){
return val.isEmpty ? "Enter First Name" : null ;
} ,
decoration: InputDecoration(
hintText: "First Name"
),
onChanged: (val){
fName = val;
},
),
SizedBox(height: 6,),
TextFormField(
validator: (val){
return val.isEmpty ? "Enter Last Name" : null ;
} ,
decoration: InputDecoration(
hintText: "Last Name"
),
onChanged: (val){
lName = val;
},
),
SizedBox(height: 6,),
TextFormField(
validator: (val){
return val.isEmpty ? "Enter Emailid" : null ;
} ,
decoration: InputDecoration(
hintText: "Email"
),
onChanged: (val){
email = val;
},
),
SizedBox(height: 6,),
TextFormField(
validator: (val){
return val.isEmpty ? "Enter Phone Number" : null ;
} ,
decoration: InputDecoration(
hintText: "Phone"
),
onChanged: (val){
phone = val;
},
),
SizedBox(height: 6,),
TextFormField(
obscureText: true,
validator: (val){
return val.isEmpty ? "Enter Password" : null ;
} ,
decoration: InputDecoration(
hintText: "Password"
),
onChanged: (val){
password = val;
},
),
SizedBox(height: 24,),
GestureDetector(
onTap: (){
signUp();
},
child: Container(
padding: EdgeInsets.symmetric(vertical: 18),
decoration: BoxDecoration(
color: Colors.blue,
borderRadius: BorderRadius.circular(30)
),
alignment: Alignment.center,
width: MediaQuery.of(context).size.width - 48,
child: Text("Register", style: TextStyle(color: Colors.white, fontSize: 16),),
),
),
SizedBox(height: 18,),
Row(
mainAxisAlignment: MainAxisAlignment.center,
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Text("Already have an account? ", style: TextStyle(fontSize: 15.5),),
GestureDetector(
onTap: (){
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => SignIn()
));
},
child: Text("Sign in", style: TextStyle(fontSize: 15.5, decoration: TextDecoration.underline),))
],
),
SizedBox(height: 80,),
],
),
),
),
),
);;
}
}
我试着给子代添加Expanded，它删除了错误，但输入数据时表格字段变得非常小。我试着用SingleChildScrollView包装列，但它给我的是下面的结果。
RenderFlex子代具有非零的flex，但传入的高度约束是无限制的。
谁能建议一下，我到底是哪里做错了？
谢谢！我正在建立一个有4-5个表单字段的表单。
你必须用SingleChildScrollView来包装你的Form widget。另外，请注意，添加SingleChildScrollView后，没有固定的高度，所以，你不能使用spacer widget。取而代之的是，你可以使用SizedBox Widget来给上面一些空间。
final _formKey = GlobalKey<FormState>();
String sName, fName, lName, email, phone, password;
AuthService authService = new AuthService();
bool _isLoading = false;
signUp() async {
if (_formKey.currentState.validate()) {
setState(() {
_isLoading = true;
});
authService.signUpWithEmailAndPass(email, password).then((value) {
if (value != null) {
setState(() {
_isLoading = false;
});
Navigator.pushReplacement(
context, MaterialPageRoute(builder: (context) => Home()));
}
});
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: appBar(context),
centerTitle: true,
backgroundColor: Colors.transparent,
elevation: 0.0,
brightness: Brightness.light,
),
body: _isLoading
? Container(
child: Center(
child: CircularProgressIndicator(),
),
)
: SingleChildScrollView(
child: Form(
key: _formKey,
child: Container(
padding: EdgeInsets.symmetric(horizontal: 24),
child: Container(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
// here you can't use spacer because their is no fix height, so you have to use SixedBox give some spacing
SizedBox(
height: 50,
),
TextFormField(
validator: (val) {
return val.isEmpty ? "Enter School Name" : null;
},
decoration: InputDecoration(hintText: "School Name"),
onChanged: (val) {
sName = val;
},
),
SizedBox(
height: 6,
),
TextFormField(
validator: (val) {
return val.isEmpty ? "Enter First Name" : null;
},
decoration: InputDecoration(hintText: "First Name"),
onChanged: (val) {
fName = val;
},
),
SizedBox(
height: 6,
),
TextFormField(
validator: (val) {
return val.isEmpty ? "Enter Last Name" : null;
},
decoration: InputDecoration(hintText: "Last Name"),
onChanged: (val) {
lName = val;
},
),
SizedBox(
height: 6,
),
TextFormField(
validator: (val) {
return val.isEmpty ? "Enter Emailid" : null;
},
decoration: InputDecoration(hintText: "Email"),
onChanged: (val) {
email = val;
},
),
SizedBox(
height: 6,
),
TextFormField(
validator: (val) {
return val.isEmpty ? "Enter Phone Number" : null;
},
decoration: InputDecoration(hintText: "Phone"),
onChanged: (val) {
phone = val;
},
),
SizedBox(
height: 6,
),
TextFormField(
obscureText: true,
validator: (val) {
return val.isEmpty ? "Enter Password" : null;
},
decoration: InputDecoration(hintText: "Password"),
onChanged: (val) {
password = val;
},
),
SizedBox(
height: 24,
),
GestureDetector(
onTap: () {
signUp();
},
child: Container(
padding: EdgeInsets.symmetric(vertical: 18),
decoration: BoxDecoration(
color: Colors.blue,
borderRadius: BorderRadius.circular(30)),
alignment: Alignment.center,
width: MediaQuery.of(context).size.width - 48,
child: Text(
"Register",
style:
TextStyle(color: Colors.white, fontSize: 16),
),
),
),
SizedBox(
height: 18,
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Text(
"Already have an account? ",
style: TextStyle(fontSize: 15.5),
),
GestureDetector(
onTap: () {
Navigator.pushReplacement(
context,
MaterialPageRoute(
builder: (context) => SignIn()));
},
child: Text(
"Sign in",
style: TextStyle(
fontSize: 15.5,
decoration: TextDecoration.underline),
))
],
),
SizedBox(
height: 80,
),
],
),
),
),
),
),
);
}
}
用'singlechildscrollview'来包装你的主体。