我试图使用dio调用API，然后遇到了这个错误。
“Future _getHomeData（）async { try { var homeDataResponse = await HomeService（）.getHomeData（））;

final classList = (homeDataResponse.data['classes']) as List;
  classes = classList.map((i) => ClassModel.fromJson(i)).toList();
  _storageService
      .writeSecureData(StorageItem("user_classes", jsonEncode(classes)));

  final examList = (homeDataResponse.data['exams']) as List;
  exams = examList.map((i) => Exam.fromJson(i)).toList();
  _storageService
      .writeSecureData(StorageItem("user_exams", jsonEncode(exams)));

  final taskList = (homeDataResponse.data['tasks']) as List;
  tasks = taskList.map((i) => Task.fromJson(i)).toList();
  _storageService
      .writeSecureData(StorageItem("user_tasks", jsonEncode(exams)));

  // for (var subject in subjects) {
  //   print("SUBJECtS ${subject.subjectName}");
  // }
} catch (error) {
  if (error is DioError) {
    throw Result.error(error.response?.data['message']);
  } else {
    throw Result.error(error.toString());
  }
}

} `