Refresh indicator doesn't update data post after caching in Flutter - flutter

Question

I am facing an issue when I pull to refresh, I need that after pull to refresh gesture new articles available will be visible in the news page, but this doesn't happen.
I created the cache system, but once I pull to refresh new data, the news page doesn't load new articles.
What can I do to solve this issue?
News page
class _NewsPageState extends State<NewsPage> {
/// News service
final ApiNewsPage categoryNews = ApiNewsPage();
late bool isLoading;
/// Start Refresh indicator upload new articles function
final NewArticlesPage updateArticles = NewArticlesPage();
ScrollController scrollController = ScrollController();
//final List<ArticleModel> _posts = [];
//
#override
void initState() {
super.initState();
refreshArticles();
}
/// Call this when the user pull down the screen
Future<void> refreshArticles() async {
Future.delayed(const Duration(seconds: 2), () {
setState(() {
updateArticles.updateArticles();
print("Uploading new articles");
//_posts.add();
});
return updateArticles.updateArticles();
});
}
/// End Refresh indicator upload new articles function
///
///
#override
Widget build(BuildContext context) {
return RefreshIndicator(
displacement: 0,
color: assofacileMainColor,
backgroundColor: Colors.white,
onRefresh: refreshArticles,
child: Container(
child: FutureBuilder<List?>(
future: categoryNews.getNewsArticles(),
builder: (context, snapshot) { // AsyncSnapshot
if (snapshot.hasData) {
if (snapshot.data?.length == 0) {
return const NoArticle();
}
return ListView.builder(
controller: scrollController,
itemCount: snapshot.data?.length++,
physics: const AlwaysScrollableScrollPhysics(),
itemBuilder: (context, i) {
return Card(
margin: const EdgeInsets.all(8),
elevation: 5,
shadowColor: Colors.black26,
color: Colors.white,
child: InkWell(
child: ClipRRect(
borderRadius: BorderRadius.circular(10),
child: Column(
mainAxisSize: MainAxisSize.min,
children: [
SizedBox(
height: 190,
width: double.infinity,
child:
Image(
image: AdvancedNetworkImage(
snapshot.data![i]["_embedded"]['wp:featuredmedia'][0]["media_details"]["sizes"]["medium"]["source_url"],
useDiskCache: true,
cacheRule: const CacheRule(maxAge: Duration(days: 1)),
),
fit: BoxFit.cover,
),
// CachedNetworkImage(
// cacheManager: CacheManager(
// Config(snapshot.data![i]["_embedded"]['wp:featuredmedia'][0]["media_details"]["sizes"]["medium"]["source_url"],
// stalePeriod: const Duration(days: 1),
// )
// ),
// //cacheManager: DioCacheManager.instance,
// imageUrl: snapshot.data![i]["_embedded"]['wp:featuredmedia'][0]["media_details"]["sizes"]["medium"]["source_url"],
// // checkIfUrlContainsPrefixHttps(
// // _post != null
// // ? _post[0].urlImageSource
// // : "https:" + snapshot.data![i]["_embedded"]['wp:featuredmedia'][0]["media_details"]["sizes"]["thumbnail"]["source_url"],
// // ),
// //snapshot.data![i]["_embedded"]["wp:featuredmedia"][0]["link"],
// //"https:" + snapshot.data![i]["_embedded"]['wp:featuredmedia'][0]["media_details"]["sizes"]["medium"]["source_url"],
// fit: BoxFit.cover,
// placeholder: (context, url) => Image.asset("assets/gif/shimmer.gif",
// width: double.infinity,
// height: 190,
// fit: BoxFit.cover,
// ),
// errorWidget: (context, url, error) => Image.asset("assets/images/unloadedImage.png",
// width: 250, height: 250),
// ),
),
// Title article
Column(
children: [
Padding(
padding: const EdgeInsets.only(left:16, top: 16, bottom: 16),
child: Row(
children: [
Expanded(
child: Text(
snapshot.data![i]["title"]["rendered"]
.replaceAll("’", "'")
.replaceAll("<p>", "")
.replaceAll("</p>", ""),
style: const TextStyle(
fontSize: 18,
fontWeight: FontWeight.w600,
fontFamily: "Raleway",
),
overflow: TextOverflow.ellipsis,
maxLines: 2,
//softWrap: false,
),
),
],
),
)
],
),
],
),
),
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => ArticlePage(data: snapshot.data?[i]),
),
);
},
),
);
},
);
} else if (snapshot.hasError) {
return const NoInternet();
} else {
/// Shimmer
return ShimmerEffect();
}
}
),
),
);
}
}
Fetch and create cache
class ApiNewsPage {
final String url = newsJsonLink;
Future<List?> getNewsArticles() async {
String nameDB = "articledata.json";
var dir = await getTemporaryDirectory();
File file = File(dir.path + "/" + nameDB);
if(file.existsSync()) {
print("Loading Articles from cache");
var jsonDB = file.readAsStringSync();
List response = json.decode(jsonDB);
return response;
} else {
var response = await http.get(Uri.parse(url));
if (response.statusCode == 200) {
//await File(nameDB).exists();
var jsonResponse = response.body;
List newArticles = json.decode(jsonResponse);
//File(nameDB).deleteSync(recursive: true);
/// save json in local file
file.writeAsStringSync(jsonResponse, flush: true, mode: FileMode.write);
print("Fetching new articles from internet");
return newArticles;
}
}
}
}
// Create new db
class NewArticlesPage {
final String url = newsJsonLink;
Future<List?> updateArticles() async {
try {
var response = await http.get(Uri.parse(url));
if (response.statusCode == 200) {
print("Fetching new articles from internet");
return jsonDecode(response.body);
} else {
return Future.error("Impossibile ricevere i dati, prova a controllare la connessione");
}// ignore: non_constant_identifier_names
} catch (SocketException) {
return Future.error("Impossibile caricare gli articoli");
}
}
}