小编che*_*uri的帖子

不确定为什么我收到错误“未处理的异常：类型 '(dynamic) => Null' 不是类型 '(String,dynamic) => void' of 'f' 的子类型”。一切似乎都正确完成，但仍然出现错误

Json link: https://androidapp.factory2homes.com/api/get-shipping-address-by-user-id/3

class ShippingAddressPage extends StatefulWidget {
  @override
  _ShippingAddressPageState createState() => _ShippingAddressPageState();
}

class _ShippingAddressPageState extends State<ShippingAddressPage> {

  List<Shipping> _shippingAddressList = List<Shipping>();

 @override
 void initState() {
   super.initState();
   _getShippingAddressByUserId();
 }


 _getShippingAddressByUserId() async {
   SharedPreferences _prefs = await SharedPreferences.getInstance();
   int _userId = _prefs.getInt('userId');
   ShippingAddressService _shippingAddressService = ShippingAddressService();
   var result = await _shippingAddressService.getShippingAddressByUserId(_userId);
   var shipping = json.decode(result.body);
   shipping.forEach((shipping){
     var model = Shipping();
     model.id = shipping['id'];
     model.name = shipping['name'];
     model.address = shipping['address']; …