I am trying to fetch News data from an API in JSON format and display it in my app.

News Class:

class News {
  final String title;
  final String desc;
  final String imgURL;
  final String url;

  News(
      {required this.title,
      required this.desc,
      required this.imgURL,
      required this.url});

  factory News.fromJSON(Map<String, dynamic> json) {
    return News(
        title: json["title"],
        desc: json["description"],
        imgURL: json["image_url"],
        url: json["url"]);
  }
}

News object getter:

Future<List<News>>? futureData;
  
  Future<List<News>> getNews() async {
    final response = await http.get(Uri.parse(
        'https://api.stockdata.org/v1/news/all?&filter_entities=true&language=en&api_token=api_token&countries=in'));
    if (response.statusCode == 200) {
      List jsonResponse = json.decode(response.body);
      return jsonResponse.map((data) => News.fromJSON(data)).toList();
    } else {
      throw Exception('Unexpected error occurred!');
    }
  }

FutureBuilder to display in the app:

FutureBuilder<List<News>>(
                future: futureData,
                builder: (context, snapshot) {
                  if (snapshot.hasData) {
                    print(snapshot);
                    List<News> data = snapshot.requireData;
                    return ListView.builder(
                        itemCount: data.length,
                        itemBuilder: (BuildContext context, int index) {
                          return Container(),
                          );
                        });
                  } else if (snapshot.hasError) {
                    return Text("${snapshot.error}");
                  }
                  // By default show a loading spinner.
                  return Center(child: CircularProgressIndicator());
                }),

I keep getting the error: type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'List' in type cast

CodePudding user response：

The response you receive from the api is of JsonObject similar to map but in the code you are trying to parse it as a list check how it looks here

your News.fromJSON() is written such that its taking only one object where as the data you are getting is of array.

 factory News.fromJSON(Map<String, dynamic> json) {
return News(
    title: json["title"],
    desc: json["description"],
    imgURL: json["image_url"],
    url: json["url"]);

}

Currently your model class can only take one object not a list. you can go through this