【发布时间】：2021-04-06 16:20:31
【问题描述】：
大家好， 我陷入了从后端获取数据但最初在应用程序启动之前错误显示在手机上的情况。 下面是错误的图像。
显示此内容后，应用程序启动。我该如何处理这个错误？我尝试了旋转套件，但它不起作用。 我想在控制台上显示这个。 下面是代码-:
import 'package:education/LogIn_SignUp/Log_In.dart';
import 'package:education/Screens/Profile_Screen.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'About_Scree.dart';
import 'Change_Password.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';
import 'dart:async';
class homeView extends StatefulWidget{
var user_id;
var user_name;
var mobile_number;
var user_address;
var user_Email;
var coaching_id;
var coaching_name;
var coaching_address;
var primary_no;
var altnumber;
var coaching_email;
homeView({
this.user_id,this.user_name,this.mobile_number,this.user_address,this.coaching_id,this.coaching_name,
this.coaching_address,this.primary_no,this.altnumber,this.coaching_email,this.user_Email
});
@override
State<StatefulWidget> createState() => homeViewState();
}
class homeViewState extends State<homeView> {
TextEditingController editingController = TextEditingController();
var showItemList = List<String>();
int count = 10;
var userid, username, mobilenumber, useraddress, userEmail, coachingid, coachingname, coachingaddress;
var primaryno, alt_number, coachingemail;
void setdata(){
setState(() {
userid = widget.user_id;
username = widget.user_name;
mobilenumber = widget.mobile_number;
useraddress = widget.user_address;
userEmail = widget.user_Email;
coachingid = widget.coaching_id;
coachingname = widget.coaching_name;
coachingaddress = widget.coaching_address;
});
}
@override
void initState(){
// showItemList.addAll(initList);
// getData();
setdata();
super.initState();
}
@override
void dispose() {
editingController.dispose();
super.dispose();
}
/// -----------------------------------------------------------------------------------------------------------------------------
/// Main Build Function for the class.
/// -----------------------------------------------------------------------------------------------------------------------------
@override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
appBar: PreferredSize(
preferredSize: Size.fromHeight(90.0),
child: AppBar(
title: Padding(
padding: const EdgeInsets.only(top: 20),
child: Text(
'$coachingname',//'${widget.coaching_name}',
style: TextStyle(
fontSize: 25.0,
letterSpacing: 4.5,
fontFamily: 'Sarif',
fontWeight: FontWeight.w300,
color: Colors.white,
),
),
),
backgroundColor: Colors.deepPurpleAccent,
centerTitle: true,
actions: <Widget>[
Column(
children: [
InkWell(
child: new IconButton(
icon: Padding(
padding: const EdgeInsets.only(top: 20),
child: Icon(Icons.exit_to_app),
),
onPressed:(){
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => LoginPage(),
));
}
),
onTap: (){
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => LoginPage()
));
},
),
],
),
],
),
),
drawer: Drawer(
child: Container(
padding: EdgeInsets.all(10),
child: ListView(
children: <Widget>[
Container(
height: 180,
decoration: BoxDecoration(
gradient: LinearGradient(colors: [
Colors.purple.shade300,
Colors.deepPurpleAccent.shade200,
]),
),
child: Column(
children: [
Padding(
padding: const EdgeInsets.only(top: 45.0, bottom: 10),
child: Card(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(55),
),
color: Colors.blue,
child: Padding(
padding: const EdgeInsets.all(10.0),
child: Icon(Icons.perm_identity_outlined, color: Colors.white,size: 30),
)
),
),
Text(
'$username',//'${widget.user_name}',
style: TextStyle(
color: Colors.white,
fontSize: 24,
letterSpacing: 2.5,
),
),
],
),
),
ListTile(
title: Text('Profile',
style: TextStyle(
fontSize: 17,
fontWeight: FontWeight.w400,
letterSpacing: 1.5,
),
),
leading: Icon(Icons.person_pin, color: Colors.blue,),
selectedTileColor: Colors.blue,
onTap: (){
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => ProfilePage(
user_id: userid, user_name:username, mobile_number:mobilenumber, user_address:useraddress,
user_Email: userEmail,
)
));
},
),
ListTile(
title: Text('Change Password',
style: TextStyle(
fontSize: 17,
fontWeight: FontWeight.w400,
letterSpacing: 1.5,
),
),
leading: Icon(Icons.security, color: Colors.blue,),
selectedTileColor: Colors.blue,
onTap: (){
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => ChangePassword()
));
},
),
ListTile(
title: Text('About',
style: TextStyle(
fontSize: 17,
fontWeight: FontWeight.w400,
letterSpacing: 1.5,
),
),
leading: Icon(Icons.info_outline, color: Colors.blue,),
selectedTileColor: Colors.blue,
onTap: (){
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => AboutScreen(
coaching_id:coachingid, coaching_name:coachingname, coaching_address:coachingaddress,
primary_no:primaryno, altnumber:alt_number, coaching_email:coachingemail
)//coaching details
));
},
),
ListTile(
title: Text(
'Rate',
style: TextStyle(
fontSize: 17,
fontWeight: FontWeight.w400,
letterSpacing: 1.5,
),
),
leading: Icon(Icons.star_border_outlined, color: Colors.blue,),
selectedTileColor: Colors.blue,
onTap: (){
},
),
Divider(
color: Colors.red,
thickness: 1,
),
SizedBox(height: 10,),
Text(
'Contact Us',
style: TextStyle(
fontSize: 20,
color: Colors.grey[800],
letterSpacing: 1.5,
fontWeight: FontWeight.w500,
),
),
SizedBox(height: 10,),
ListTile(
title: Text('Share',
style: TextStyle(
fontSize: 17,
fontWeight: FontWeight.w400,
letterSpacing: 1.5,
),
),
leading: Icon(Icons.share, color: Colors.blue,),
selectedTileColor: Colors.blue,
onTap: (){
},
),
ListTile(
title: Text('Privacy Policy',
style: TextStyle(
fontSize: 17,
fontWeight: FontWeight.w400,
letterSpacing: 1.5,
),
),
leading: Icon(Icons.privacy_tip, color: Colors.blue,),
selectedTileColor: Colors.blue,
onTap: (){
},
),
ListTile(
title: Text(
'LogOut',
style: TextStyle(
fontSize: 17,
fontWeight: FontWeight.w400,
letterSpacing: 1.5,
),
),
leading: Icon(Icons.logout, color: Colors.blue,),
selectedTileColor: Colors.blue,
onTap: (){
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => LoginPage()
));
},
),
],
),
),
),
body: Container(),
),
);
}
}
我可以有一些想法来处理这件事吗？
这是控制台上显示的异常 -:
════════ Exception caught by widgets library ═══════════════════════════════════════════════════════
The following assertion was thrown building LoginPage(dirty, dependencies: [MediaQuery], state: LoginPageState#6cbef(ticker active)):
LoginPageState is a SingleTickerProviderStateMixin but multiple tickers were created.
A SingleTickerProviderStateMixin can only be used as a TickerProvider once.
If a State is used for multiple AnimationController objects, or if it is passed to other objects and those objects might use it more than one time in total, then instead of mixing in a SingleTickerProviderStateMixin, use a regular TickerProviderStateMixin.
The relevant error-causing widget was:
LoginPage file:///C:/Users/PALAK/AndroidStudioProjects/education/lib/main.dart:35:7
When the exception was thrown, this was the stack:
#0 SingleTickerProviderStateMixin.createTicker.<anonymous closure> (package:flutter/src/widgets/ticker_provider.dart:121:7)
#1 SingleTickerProviderStateMixin.createTicker (package:flutter/src/widgets/ticker_provider.dart:130:6)
#2 new AnimationController (package:flutter/src/animation/animation_controller.dart:248:21)
#3 LoginPageState.build (package:education/LogIn_SignUp/Log_In.dart:250:21)
#4 StatefulElement.build (package:flutter/src/widgets/framework.dart:4744:28)
下面是登录页面的代码-:
import 'package:education/Screens/Home_View.dart';
import 'package:flutter/material.dart';
import 'package:flutter_spinkit/flutter_spinkit.dart';
import 'package:form_field_validator/form_field_validator.dart';
import 'dart:convert';
import 'package:http/http.dart' as http;
import 'SignUp.dart';
class LoginPage extends StatefulWidget{
@override
State<StatefulWidget> createState() {
return LoginPageState();
}
}
class LoginPageState extends State<LoginPage>with SingleTickerProviderStateMixin {
bool isLoading = false;
GlobalKey<FormState> formkey = GlobalKey<FormState>();
final FocusNode focusNode = new FocusNode();
var usermail, password, C_id;
TextEditingController userEmail1 = new TextEditingController();
TextEditingController userPassword1= new TextEditingController();
var userid, username, mobilenumber, useraddress, coachingid, coachingname, coachingaddress, primaryno, altno, coachingemail;
var Coaching_name, Coaching_id;
var data;
Future<http.Request> getData() async
{
var client = new http.Client();
final response = await client.get('http://192.168.0.104:5000/coaching_detail');
final responseJson = json.decode(response.body);
if(responseJson == null) {
setState(() {
Container(
color: Colors.white,
child: isLoading ? SpinKitSquareCircle(
color: Colors.red,
size: 50.0,
controller: AnimationController(vsync: this,duration: const Duration(seconds: 3)),
): Container(height: 200,)
//isLoading == true ? Text('Loading ...') : Text('Loading ...'),
);
});
}
else {
setState(() {
dynamic coaching_id = responseJson['coachid'];
dynamic coaching_name = responseJson['coachname'];
Coaching_name = coaching_name;
Coaching_id = coaching_id;
data = responseJson;
});
}
print(responseJson);
client.close();
}
int i = 2;
Future signInWithUserNameAndPassword(String email, String Password, String coachid) async {
try {
final http.Response response = await http.post(
'http://192.168.0.104:5000/user_login',
headers: <String, String>{
'Content-Type': 'application/json; charset=UTF-8',
},
body: jsonEncode(<String, String>{
'useremail': email,
'userpassword': Password,
'coachid' : coachid,
}),
);
final responseJson = json.decode(response.body);
print(responseJson);
if (responseJson['coach_id'] != null) {
print('success');
print(responseJson);
setState(() {
dynamic user_id = responseJson['userid'];
dynamic user_name = responseJson['user_name'];
dynamic mobile_number = responseJson['mobile_number'];
dynamic user_address = responseJson['user_address'];
dynamic coaching_id = responseJson['coach_id'];
dynamic coach_name = responseJson['coach_name'];
dynamic coach_address = responseJson['coach_address'];
dynamic primary_no = responseJson['primary_no'];
dynamic alt_number = responseJson['alt_number'];
dynamic coaching_email = responseJson['coaching_email'];
userid = user_id;
username = user_name;
mobilenumber = mobile_number;
useraddress = user_address;
coachingid = coaching_id;
coachingname = coach_name;
coachingaddress = coach_address;
primaryno = primary_no;
altno = alt_number;
coachingemail = coaching_email;
});
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => homeView(
user_id: userid, user_name:username, mobile_number:mobilenumber, user_address:useraddress,
coaching_id:coachingid, coaching_name:coachingname, coaching_address:coachingaddress,
primary_no:primaryno, altnumber:altno, coaching_email:coachingemail, user_Email:usermail,
),
));
}
else{
print('fail');
showDialog(
context: context,
builder: (BuildContext context) {
return AlertDialog(
title: Text("Error"),
content: Text("Incorrect Credentials"),
actions: [
FlatButton(
child: Text("Ok"),
onPressed: () {
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context)=> LoginPage()
));
},
)
],
);
});
}
}
catch (e) {
print(e.toString());
}
}
signIn(){
if(formkey.currentState.validate()){
setState(() {
isLoading = true;
});
usermail = userEmail1.text;
password = userPassword1.text;
C_id = Coaching_id[i].toString();
signInWithUserNameAndPassword(usermail, password, C_id);
}
}
@override
void initState() {
super.initState();
getData();
}
@override
void dispose(){
userEmail1.dispose();
userPassword1.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
double height = MediaQuery
.of(context)
.size
.height;
double width = MediaQuery
.of(context)
.size
.width;
return Scaffold(
body: isLoading ? SpinKitSquareCircle(
color: Colors.red,
size: 50.0,
controller: AnimationController(vsync: this,duration: const Duration(seconds: 3)),
)
: Center(
child: SingleChildScrollView(
child: Form(
key: formkey,
// autovalidate: true,
child: Column(
children: <Widget>[
Container(
width: width,
height: height,
padding: const EdgeInsets.all(16.0),
decoration: BoxDecoration(
gradient: LinearGradient(
colors: [Colors.lightBlueAccent, Colors.blueAccent],
),
),
child: Column(
children: <Widget>[
Container(
margin: const EdgeInsets.only(top: 40.0, bottom: 20.0),
height: 50,
),
Text(
'${Coaching_name[i]}',
style: TextStyle(
fontSize: 45.0,
letterSpacing: 4.5,
fontFamily: 'Sarif',
fontWeight: FontWeight.w300,
color: Colors.white,
),
),
SizedBox(height: 130.0),
TextFormField(
controller: userEmail1,
decoration: InputDecoration(
contentPadding: const EdgeInsets.all(16.0),
prefixIcon: Container(
padding:
const EdgeInsets.only(top: 16.0, bottom: 16.0),
margin: const EdgeInsets.only(right: 8.0),
decoration: BoxDecoration(
color: Colors.white,
),
child: Icon(
Icons.person,
color: Colors.purpleAccent,
)),
hintText: "enter your email",
hintStyle: TextStyle(color: Colors.white54),
border: OutlineInputBorder(
borderRadius: BorderRadius.circular(30.0),
borderSide: BorderSide.none),
filled: true,
fillColor: Colors.white.withOpacity(0.1),
),
validator: MultiValidator(
[
RequiredValidator(errorText: 'Required'),
// EmailValidator(errorText: 'not a valid Email'),
]
),
onSaved: (user) => usermail(user),
),
SizedBox(height: 20.0),
TextFormField(
controller: userPassword1,
decoration: InputDecoration(
contentPadding: const EdgeInsets.all(16.0),
prefixIcon: Container(
padding:
const EdgeInsets.only(top: 16.0, bottom: 16.0),
margin: const EdgeInsets.only(right: 8.0),
decoration: BoxDecoration(
color: Colors.white,
),
child: Icon(
Icons.lock,
color: Colors.purpleAccent,
)),
hintText: "enter your password",
hintStyle: TextStyle(color: Colors.white54),
border: OutlineInputBorder(
borderRadius: BorderRadius.circular(30.0),
borderSide: BorderSide.none),
filled: true,
fillColor: Colors.white.withOpacity(0.1),
),
obscureText: true,
validator: MultiValidator(
[
MinLengthValidator(4,
errorText: 'should be atleast 6 characters'),
MaxLengthValidator(10,
errorText: 'should not be more than 10 characters'),
RequiredValidator(errorText: 'Required'),
]
),
),
SizedBox(height: 30.0),
SizedBox(
width: double.infinity,
child: RaisedButton(
color: Colors.white,
textColor: Colors.purpleAccent,
padding: const EdgeInsets.all(20.0),
child: Text("Login".toUpperCase()),
onPressed: () {
NavigationMode.directional;
signIn();
},
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(30.0)
),
),
),
SizedBox(height: 25,),
Align(
alignment: Alignment.bottomCenter,
child: Column(
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget>[
SizedBox(height: 20,),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text("Don\'t have an account?",
style: TextStyle(
color: Colors.white,
fontSize: 18,
),
),
FlatButton(
child: Text("Sign in",
style: TextStyle(
color: Colors.amberAccent,
fontSize: 18,
),
),
textColor: Colors.indigo,
onPressed: (){
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => signUp()
));
},
)
],
),
],
),
),
],
),
),
],
),
),
),
),
);
}
}
【问题讨论】：
-
能否从调试控制台复制并粘贴错误代码？
-
能不能给控制台stacktrace。还要指出控制台指向您的错误行。
-
实际上，这个页面加载时出现的代码并没有任何错误。
-
你能分享你的登录页面的代码吗？
-
是的，我分享了上面的代码
标签： api flutter error-handling flutter-layout