dart - 获取 _InternalLinkedHashMap' is not a subtype of type ' FutureOr'

Question

我是 Dart/Flutter 的新手，我正在尝试获取使用网络服务的 future 结果:

 Future<Map> _readData() async {
   (...)


http.Response response = await http.post(
    request,
    headers: {
      "SOAPAction": "http://www.totvs.com/IwsConsultaSQL/RealizarConsultaSQL",
      "Content-Type": "text/xml;charset=UTF-8",
      "Authorization": "Basic bWVzdHJlOnRvdHZz",
      "cache-control": "no-cache"
    },
    body: utf8.encode(requestBody),
    encoding: Encoding.getByName("UTF-8")
).then((onValue){

  (...)


  var dataFinal = jsonDecode(jsondataFinal);

  return  dataFinal ;
});

在我的初始状态下，我调用了这个函数，所以我可以使用这个结果来构建我的布局:

     @override
  void initState () {
    super.initState();
    _readData().then((data){
      setState(() {
        print(data);

      });

    });

  }

我总是得到这个异常(exception):

_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'FutureOr<Response>'

对我做错了什么有什么想法吗？

谢谢

Answer 1

此代码是否出现此错误？

Future<Map> _readData() async {
  //...
  http.Response response = await http.post(
    request,
    headers: {
      "SOAPAction": "http://www.totvs.com/IwsConsultaSQL/RealizarConsultaSQL",
      "Content-Type": "text/xml;charset=UTF-8",
      "Authorization": "Basic bWVzdHJlOnRvdHZz",
      "cache-control": "no-cache"
    },
    body: utf8.encode(requestBody),
    encoding: Encoding.getByName("UTF-8")
  );
  //...
  var dataFinal = jsonDecode(jsondataFinal);
  return  dataFinal ;
}