Image not uploading in DIO 4 and above - flutter

Question

Greeting everyone, my image is not uploading to my server when i update to DIO 4.0.0 and above. The same code works for DIO version below 4.0.0 . Below is the upload code. Kindly help me out. Thanks
Future<dynamic> upload(String url, BuildContext context,
{List<File> files,
Map body,
FileCount count = FileCount.MULTIPLE,
authorize = true}) async {
BaseOptions options = await getOptions(validate: authorize);
dynamic response, serverResponse;
List<MultipartFile> uploadFiles = [];
FormData requestData;
try {
Dio dio = new Dio(options)..interceptors.add(Logging());
(dio.httpClientAdapter as DefaultHttpClientAdapter).onHttpClientCreate =
(client) {
SecurityContext sc = new SecurityContext();
HttpClient httpClient = new HttpClient(context: sc);
//allow all cert
httpClient.badCertificateCallback =
(X509Certificate cert, String host, int port) => true;
return httpClient;
};
// add files to uploadFiles array
if (files.length > 0) {
for (var index = 0; index < files.length; index++) {
MultipartFile file = MultipartFile.fromFileSync(files[index].path,
filename: basename(files[index].path),contentType:MediaType.parse('image/jpg'));
uploadFiles.add(file);
}
print("file the request: $uploadFiles");
requestData = FormData.fromMap({"file": uploadFiles});
} else {
requestData = FormData();
}
body.forEach((key, value) {
MapEntry<String, String> data = new MapEntry(key, '$value');
requestData.fields.add(data);
});
print("sending the request: ${uploadFiles.asMap().values}");
serverResponse = await dio.post(
url,
data: requestData,
options: new Options(contentType: 'multipart/form-data'),
onSendProgress: (int sent, int total) {
print('$sent $total');
},
);
print("Server Replied: $serverResponse}");
print(serverResponse.data);
//check for connection errors
if (serverResponse.statusCode < 200 || serverResponse.statusCode > 400) {
return _decoder.convert(
'{"success":false,"message":"${LocalText.of(context).load("error_executing_request")}"}');
}
response = _decoder.convert(serverResponse.data);
print("Response: $response");
} on DioError catch (e) {
// The request was made and the server responded with a status code
// that falls out of the range of 2xx and is also not 304.
if (e.response != null) {
print(e.response.data);
print(e.response.headers);
// print(e.response.request);
response = _decoder.convert(
'{"success":false,"message":"${LocalText.of(context).load("server_error")}"}');
} else {
// Something happened in setting up or sending the request that triggered an Error
print(e.message);
response =
_decoder.convert('{"success":false,"message":"' + e.message + '"}');
}
} catch (error) {
return _decoder.convert(
'{"success":false,"message":"${LocalText.of(context).load("error_executing_request")}"}');
}
return response;
}