问题：
发生异常_TypeError（类型“List”不是类型“Map”的子类型）
墨承泽
我对getruangfasiliti方法有问题。有没有办法修复这个错误？我已经为此工作了好几个星期了。
尝试这个，但它不是我想要的。我要得到这个物体的所有数据
Future<List> getruangfasiliti() async {
final response = await http.get(BaseUrl.lihatruangfasiliti(widget.barcode));
return jsonDecode(response.body);
}
下面是我的代码以及如何修复错误。我不知道我的错在哪里
模型Aduan.dart
class Aduan {
final String aduan_id;
final String tarikhaduan;
final String ruang_id;
final String fasiliti_id;
final String maklumat;
final String gambaraduan;
final String status;
final String idpengguna;
final String namaruang;
final String namafasiliti;
Aduan({
this.aduan_id,
this.tarikhaduan,
this.ruang_id,
this.fasiliti_id,
this.maklumat,
this.gambaraduan,
this.status,
this.idpengguna,
this.namaruang,
this.namafasiliti
});
factory Aduan.fromJson(Map<String, dynamic> json) {
return Aduan(
aduan_id: json['aduan_id'],
tarikhaduan: json['tarikhaduan'],
ruang_id: json['ruang_id'],
fasiliti_id: json['fasiliti_id'],
maklumat: json['maklumat'],
gambaraduan: json['gambaraduan'],
status: json['status'],
idpengguna: json['idpengguna'],
namaruang: json['namaruang'],
namafasiliti: json['namafasiliti'],
);
}
}
阿杜安。飞奔
import 'dart:convert';
import 'package:eaduanfsktm/api.dart';
import 'package:eaduanfsktm/sejarahaduan.dart';
import 'package:fluttertoast/fluttertoast.dart';
import 'package:http/http.dart' as http;
import 'package:eaduanfsktm/model/modelRuangFasiliti.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'dart:io';
import 'package:image_picker/image_picker.dart';
import 'dart:math' as Math;
import 'package:image/image.dart' as Img;
import 'package:path_provider/path_provider.dart';
import 'dart:async';
import 'package:async/async.dart';
import 'package:path/path.dart';
class BorangAduan extends StatefulWidget {
final String idpengguna, barcode;
BorangAduan(this.idpengguna, this.barcode);
@override
_BorangAduanState createState() => _BorangAduanState();
}
class _BorangAduanState extends State<BorangAduan> {
final _key = new GlobalKey<FormState>();
final GlobalKey<ScaffoldState> _scaffoldKey = new GlobalKey<ScaffoldState>();
RuangFasiliti ruangfasiliti;
TextEditingController controllerruang_id;
TextEditingController controllerfasiliti_id;
TextEditingController controller_namaruang;
TextEditingController controller_namafasiliti;
TextEditingController controllermaklumat = new TextEditingController();
File _image;
Future<RuangFasiliti> getruangfasiliti() async {
final response = await http.get(BaseUrl.lihatruangfasiliti(widget.barcode));
if (response.statusCode == 200) {
setState(() {
ruangfasiliti = RuangFasiliti.fromJson(jsonDecode(response.body));
});
setState(() {
controllerruang_id =
new TextEditingController(text: "${ruangfasiliti.ruang_id}");
controllerfasiliti_id =
new TextEditingController(text: "${ruangfasiliti.fasiliti_id}");
controller_namaruang =
new TextEditingController(text: " ${ruangfasiliti.namaruang}");
controller_namafasiliti =
new TextEditingController(text: " ${ruangfasiliti.namafasiliti}");
});
return ruangfasiliti;
}
}
// @override
// void dispose() {
// controllerruang_id.dispose();
// controllerfasiliti_id.dispose();
// controller_namaruang.dispose();
// controllerruang_id.dispose();
// controller_namafasiliti.dispose();
// super.dispose();
// }
@override
void initState() {
getruangfasiliti();
super.initState();
}
@override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
key: _scaffoldKey,
appBar: AppBar(
title: Text("Borang Aduan"),
),
body: ListView(
padding: EdgeInsets.all(2.0),
children: <Widget>[
FutureBuilder<RuangFasiliti>(
future: getruangfasiliti(),
builder: (context, snapshot) {
if (snapshot.hasData) {
return aduanbox();
} else if (snapshot.hasError) {
return Text("${snapshot.error}");
}
return Center(child: CircularProgressIndicator());
},
),
SizedBox(height: 10.0),
],
),
),
);
}
Widget aduanbox() {
return Center(
child: Form(
key: _key,
child: Card(
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Column(
children: <Widget>[
new Row(
mainAxisSize: MainAxisSize.max,
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
Expanded(
child: Container(
child: new TextFormField(
controller: controllerfasiliti_id,
readOnly: true,
decoration: InputDecoration(
labelText: "KOD FASILITI",
),
),
),
flex: 2,
),
SizedBox(width: 10.0),
Expanded(
child: Container(
child: new TextFormField(
controller: controller_namafasiliti,
readOnly: true,
decoration: InputDecoration(
labelText: "NAMA FASILITI",
),
),
),
flex: 2,
),
],
),
new Row(
mainAxisSize: MainAxisSize.max,
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
Expanded(
child: Container(
child: new TextFormField(
controller: controllerruang_id,
readOnly: true,
decoration: InputDecoration(
labelText: "KOD LOKASI",
),
),
),
flex: 2,
),
SizedBox(width: 10.0),
Expanded(
child: Container(
child: new TextFormField(
controller: controller_namaruang,
readOnly: true,
decoration: InputDecoration(
labelText: "LOKASI",
),
),
),
flex: 2,
),
],
),
TextFormField(
controller: controllermaklumat,
validator: (value) {
if (value.isEmpty) {
return 'Masukkan Maklumat Kerosakan';
}
return null;
},
decoration: InputDecoration(
labelText: "MAKLUMAT",
hintText: "Masukkan maklumat kerosakan"),
),
SizedBox(height: 10.0),
Row(
children: <Widget>[
RaisedButton(
child: Icon(Icons.image),
onPressed: getImageGallery,
),
SizedBox(width: 5.0),
RaisedButton(
child: Icon(Icons.camera_alt),
onPressed: getImageCamera,
),
],
),
SizedBox(height: 10.0),
Container(
alignment: Alignment.centerLeft,
child: _image == null
? new Text("Tiada imej !")
: new Image.file(_image),
),
SizedBox(height: 10.0),
Container(
height: 45.0,
child: GestureDetector(
onTap: () {
if (_key.currentState.validate()) {
tambahaduan(_image);
}
},
child: Material(
borderRadius: BorderRadius.circular(10.0),
color: Colors.blueAccent,
elevation: 7.0,
child: Center(
child: Text(
'HANTAR',
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontFamily: 'Montserrat'),
),
),
),
),
),
],
),
),
),
),
);
}
Future getImageGallery() async {
var imageFile = await ImagePicker.pickImage(source: ImageSource.gallery);
final tempDir = await getTemporaryDirectory();
final path = tempDir.path;
int rand = new Math.Random().nextInt(100000);
Img.Image image = Img.decodeImage(imageFile.readAsBytesSync());
Img.Image smallerImg = Img.copyResize(image, width: 500);
var compressImg = new File("$path/image_$rand.jpg")
..writeAsBytesSync(Img.encodeJpg(smallerImg, quality: 85));
setState(() {
_image = compressImg;
});
}
Future getImageCamera() async {
var imageFile = await ImagePicker.pickImage(source: ImageSource.camera);
final tempDir = await getTemporaryDirectory();
final path = tempDir.path;
int rand = new Math.Random().nextInt(100000);
Img.Image image = Img.decodeImage(imageFile.readAsBytesSync());
Img.Image smallerImg = Img.copyResize(image, width: 500);
var compressImg = new File("$path/image_$rand.jpg")
..writeAsBytesSync(Img.encodeJpg(smallerImg, quality: 85));
setState(() {
_image = compressImg;
});
}
Future tambahaduan(File _image) async {
var stream = new http.ByteStream(DelegatingStream.typed(_image.openRead()));
var length = await _image.length();
var uri = Uri.parse((BaseUrl.tambahaduan()));
var request = new http.MultipartRequest("POST", uri);
var multipartFile = new http.MultipartFile("aduanimages", stream, length,
filename: basename(_image.path));
request.fields['fasiliti_id'] = controllerfasiliti_id.text;
request.fields['ruang_id'] = controllerruang_id.text;
request.fields['maklumat'] = controllermaklumat.text;
request.fields['idpengguna'] = widget.idpengguna;
request.files.add(multipartFile);
var response = await request.send();
if (response.statusCode == 200) {
print("Image Uploaded");
setState(
() {
Fluttertoast.showToast(
msg: "Aduan Berjaya",
toastLength: Toast.LENGTH_LONG,
gravity: ToastGravity.CENTER,
backgroundColor: Colors.black,
textColor: Colors.white,
fontSize: 18.0,
);
Navigator.of(this.context).push(CupertinoPageRoute(
builder: (BuildContext context) => SejarahAduan()));
},
);
} else {
print("Upload Failed");
}
response.stream.transform(utf8.decoder).listen((value) {
print(value);
});
}
}
这是我的错误
共有1个答案
严成礼
List<RuangFasiliti> ruangfasiliti;
Future<RuangFasiliti> getruangfasiliti() async {
final response = await http.get(BaseUrl.lihatruangfasiliti(widget.barcode));
if (response.statusCode == 200) {
var body = jsonDecode(response.body);
setState(() {
if(body is List) //check if it's a List
ruangfasiliti = List<RuangFasiliti>.from(body.map(map) => RuangFasiliti.fromJson(map));
if(body is Map) //check if it's a Map
ruangfasiliti = [RuangFasiliti.fromJson(body)];
controllerruang_id =
new TextEditingController(text: "${ruangfasiliti.ruang_id}");
controllerfasiliti_id =
new TextEditingController(text: "${ruangfasiliti.fasiliti_id}");
controller_namaruang =
new TextEditingController(text: " ${ruangfasiliti.namaruang}");
controller_namafasiliti =
new TextEditingController(text: " ${ruangfasiliti.namafasiliti}");
});
return ruangfasiliti;
}
}
这段代码允许您保存一个列表ruangfasiliti，检查解码的json是映射还是列表，并相应地保存它，但正如其他注释所说，您应该提供并检查json文件的格式，以避免此类问题。如果您的JSON总是返回一个列表，那么只需创建一个列表体变量而不检查对象的类型就很容易了
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