问题描述
我正在尝试显示没有 ListView 的 Laravel Api 响应数据，我在其中获取了 api 响应，但无法在 Flutter 中显示没有 ListView.builder 的数据，甚至无法在 setState 中定义响应() 方法关于 .
我的代码如下：
class ProfilePage extends StatefulWidget {
final String scratchCard;
const ProfilePage({Key key,this.scratchCard}) : super(key: key);
@override
_ProfilePageState createState() => _ProfilePageState( scratchCard);
}
class _ProfilePageState extends State<ProfilePage> {
// Map profile = jsonDecode(result.body);
// List<Map<String,dynamic>> profile;
bool isLoading = false;
String student_name;
bool _visible = false;
String scratchCard;
String text;
String user;
String email;
String institute;
String mobile;
String referral_code;
String reg_no;
String name;
String first_name;
String last_name;
String subject_name;
String standard_name;
String icon;
var institute_mobile;
var institute_icon;
var subject;
var standard;
var student;
bool premium;
_ProfilePageState(this.scratchCard);
@override
void initState() {
super.initState();
this.getProfileDetails();
}
@override
void dispose() {
super.dispose();
}
getProfileDetails() async {
setState(() {
isLoading = true;
});
var response = await CallApi().getProfile();
print(response.body);
if(response.statusCode == 200){
var items = json.decode(response.body)['user'];
setState(() {
// institute = items.student[0].institute.name;
student_name = items['user']['first_name'] + ' ' + items['user']['last_name'];
institute = items['student'][0]['institute']['name'];
email = items['user']['email'];
mobile = items['user']['mobile'];
referral_code = items['user']['referral_code'];
reg_no = items['student'][0]['reg_no'];
institute_mobile = items['student'][0]['institute']['user']['mobile'];
institute_icon = items['student'][0]['institute']['icon'];
subject=items.subject_name;
this.standard=items['subject_name']['standard_name'];
isLoading = false;
});
}else{
// tableData = [];
isLoading = false;
}
}
@override
Widget build(BuildContext context) {
var subject;
return Scaffold(
extendBodyBehindAppBar: true,body: Stack(
children: <Widget>[
Container(
height: 275,decoration: Boxdecoration(
borderRadius: BorderRadius.vertical(bottom: Radius.circular(30.0)),color: Constants.blueLight,),child: Stack(
children: <Widget>[
Positioned(
child: Image.asset("assets/images/blob_2.png",width: 332,height: 323,color: Constants.blueDark),top: -80,right: -110,Positioned(
child: Image.asset("assets/images/blob_1.png",width: 255,height: 267,color: Constants.blueMain),top: 20,left: -80,],// HeaderInner(),ListView(
scrollDirection: Axis.vertical,physics: NeverScrollableScrollPhysics(),shrinkWrap: true,children: <Widget>[
Container(
// color: Colors.blue[600],// height: 40 * SizeConfig.heightMultiplier,height: 100,child: Padding(
padding: EdgeInsets.only(left: 20.0,right: 20.0,top: 0 ),child: Column(
children: <Widget>[
Row(
children: <Widget>[
Container(
height:60,width: 60,// height: 11 * SizeConfig.heightMultiplier,// width: 22 * SizeConfig.widthMultiplier,decoration: Boxdecoration(
shape: BoxShape.circle,image: decorationImage(
fit: BoxFit.cover,image: NetworkImage('https://github.com/slackvishal/Flutter_traveler_profile_app/blob/master/assets/profileimg.png?raw=true'))
),SizedBox(width: 10,Column(
crossAxisAlignment: CrossAxisAlignment.start,children: <Widget>[
Text(student_name.toString(),style: TextStyle(
color: Colors.white,// fontSize: 3 * SizeConfig.textMultiplier,fontWeight: FontWeight.bold,fontSize: 16
),Text(email.toString(),style: TextStyle(
color: Colors.white70,fontSize: 13
// fontSize: 1.9 * SizeConfig.textMultiplier,// SizedBox(height: ),Row(
mainAxisAlignment: MainAxisAlignment.end,children: <Widget>[
Container(
decoration: Boxdecoration(
border: Border.all(color: Colors.white60),borderRadius: BorderRadius.circular(5.0),child: Padding(
padding: const EdgeInsets.all(8.0),child: Text("EDIT PROFILE",style: TextStyle(
color: Colors.white60,Container(
height: 550,padding: EdgeInsets.fromLTRB(
Constants.mainPadding,Constants.mainPadding * 1.5,Constants.mainPadding,Constants.mainPadding
),decoration: Boxdecoration(
borderRadius: BorderRadius.vertical(top: Radius.circular(50.0)),color: Colors.white,child:ListView(
scrollDirection: Axis.vertical,children: [
InkWell(
onTap: () {
Navigator.push(
context,MaterialPageRoute(builder: (context) => Standard()));
},child: Container(
width: double.infinity,padding: EdgeInsets.only(left:20.0,right: 20,top: 13,bottom: 13),margin: EdgeInsets.only(bottom: 10),decoration: Boxdecoration(
borderRadius: BorderRadius.circular(30.0),color: Constants.lightPink,child: Row(
children: <Widget>[
Icon(Icons.location_city,color: Constants.textDark,size: 20,// Image.asset("assets/images/education-logo.jpg",width: 40,height: 40),SizedBox(width: 30.0),Expanded(
child: Row(
crossAxisAlignment: CrossAxisAlignment.start,mainAxisAlignment: MainAxisAlignment.start,children: <Widget>[
Container(
margin: EdgeInsets.only(top: 0),child:Text( 'Institute : ',style: TextStyle(
fontSize: 17,fontWeight: FontWeight.w500,color: Constants.textDark
),SizedBox(width: 5,Container(
margin: EdgeInsets.only(top: 2),child: Text(institute.toString(),style: TextStyle(
fontSize: 14,fontWeight: FontWeight.w400,InkWell(
onTap: () {
// Navigator.push(
// context,MaterialPageRoute(builder: (context) => Standard()));
},child: Container(
width: double.infinity,decoration: Boxdecoration(
borderRadius: BorderRadius.circular(30.0),color: Constants.lightYellow,child: Row(
children: <Widget>[
Icon(Icons.phone,Expanded(
child: Row(
crossAxisAlignment: CrossAxisAlignment.start,children: <Widget>[
Container(
margin: EdgeInsets.only(top: 0),child:Text( "Mobile: ",style: TextStyle(
fontSize: 17,color: Constants.textDark
),Container(
margin: EdgeInsets.only(top: 2),child: Text(mobile.toString(),style: TextStyle(
fontSize: 14,SizedBox(height: 5,)
),InkWell(
onTap: () {
Navigator.push(
context,color: Constants.lightBlue,child: Row(
children: <Widget>[
Icon(Icons.code,child:Text( "Referral Code: ",child: Text(referral_code.toString(),color: Constants.lightViolet,child: Row(
children: <Widget>[
Icon(Icons.confirmation_number,child:Text( "Registration No.: ",child: Text(reg_no.toString(),color: Constants.lightLime,child: Row(
children: <Widget>[
Icon(Icons.report,color: Constants.textDark),child:Text( "Referral Percentage: ",child: Text("5%",])
]),);
}
}
我在下面收到此错误：
E/Flutter ( 8258): [ERROR:Flutter/lib/ui/ui_dart_state.cc(186)] Unhandled Exception: NoSuchMethodError: The method '[]' was called on null.
E/Flutter ( 8258): Receiver: null
E/Flutter ( 8258): Tried calling: []("first_name")
E/Flutter ( 8258): #0 Object.noSuchMethod (dart:core-patch/object_patch.dart:54:5)
E/Flutter ( 8258): #1 _ProfilePageState.getProfileDetails.<anonymous closure> (package:spotway_app/screens/profile.dart:100:36)
E/Flutter ( 8258): #2 State.setState (package:Flutter/src/widgets/framework.dart:1089:30)
E/Flutter ( 8258): #3 _ProfilePageState.getProfileDetails (package:spotway_app/screens/profile.dart:97:7)
E/Flutter ( 8258): <asynchronous suspension>
解决方法
第三行错误说Tried calling: []("first_name")
此处 [] 表明您可能从 var items = json.decode(response.body)['user'];
获取空值
您的回复是否包含标题为 user 的键？
打印您的回复并查看详细结构以映射您所需的键/值。
我用最少的数据尝试过这样的方法，它正在运行，
此外，我已将数据存储在 Map<String,dynamic> 中。
String getData() {
String data = '{"user":{"id":779,"first_name":"test","last_name":"demo","email":"[email protected]","mobile":9090909090,"email_verified_at":null,"role_id":5}}';
Map<String,dynamic> d = jsonDecode(data);
print(d['user']['id']);
return d['user']['first_name'];
}
flutter 中的代码结构是这样的，您必须为数组索引指定一个数字。
例如::
变量名 = json_decode(response.body)[1]['name']