Flutter Fetching and looping in json data - json

Question

since im newbie in flutter i follow a tutorial to build a news app, so i made the class of fetching data and all its fine, when i'm executing the app i have the error in the getting data method ! can some one explain what'is wrong in this code !!
the error code :
[ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'Iterable<dynamic>'
the Class code :
class FetchDataClass {
late String author;
late String title;
late String description;
late String url;
late String urlToImage;
late String publishedAt;
late String content;
FetchDataClass(this.author, this.title, this.description, this.url, this.urlToImage, this.publishedAt, this.content );
FetchDataClass.fromJson(Map<String, dynamic> jsonData) {
author = jsonData['author'];
title = jsonData['title'];
description = jsonData['description'];
url = jsonData['url'];
urlToImage = jsonData['urlToImage'];
publishedAt = jsonData['publishedAt'];
content = jsonData['content'];
}
}
Fetshing data :
List<FetchDataClass> listofdata = List<FetchDataClass>.empty();
Future<List<FetchDataClass>> loadNews() async {
var response = await http.get(Uri.parse('https://newsapi.org/v2/everything?q=coronavirus&from=2021-09-10&sortBy=publishedAt&apiKey='));
List<FetchDataClass> news = List<FetchDataClass>.empty();
if(response.statusCode == 200) {
dynamic notesJson = json.decode(response.body);
for(dynamic noteJson in notesJson) { /// here the issue
print(11111);
news.add(FetchDataClass.fromJson(noteJson));
}
}
return news;
}
#override
void initState() {
loadNews().then((value) {setState(() {
listofdata.addAll(value);
});});
super.initState();
}

Answer 1

If your API have all data match with model you can try this
class FetchDataClass {
String author;
String title;
String description;
String url;
String urlToImage;
String publishedAt;
String content;
FetchDataClass(
{required this.author,
required this.title,
required this.description,
required this.url,
required this.urlToImage,
required this.publishedAt,
required this.content});
factory FetchDataClass.fromJson(Map<String, dynamic> jsonData) {
return FetchDataClass(
author: jsonData['author'],
title: jsonData['title'],
description: jsonData['description'],
url: jsonData['url'],
urlToImage: jsonData['urlToImage'],
publishedAt: jsonData['publishedAt'],
content: jsonData['content'],
);
}
}
and Fetch data service
List<FetchDataClass> listofdata = List<FetchDataClass>.empty();
Future<List<FetchDataClass>> loadNews() async {
var response = await http.get(Uri.parse('https://newsapi.org/v2/everything?q=coronavirus&from=2021-09-10&sortBy=publishedAt&apiKey='));
List<FetchDataClass> news = List<FetchDataClass>.empty();
if(response.statusCode == 200) {
final notesJson = json.decode(response.body);
///final news = List<FetchDataClass>.from(
/// notesJson.map((model) => FetchDataClass.fromJson(model)));
final news = FetchDataClass.fromJson(model);
}
return news;
}
Cause when you json in model type is Map<String,dynamic> but in fetching data you set dynamic notesJson it's wrong type for this. I fixed for you model and service call api, try and if some issue you can text for me to help.