如何使用延期响应解决JSON改装错误 [英] How to solve JSON retrofit error with Deferred Response

问题描述

我遵循了教程: https: //android.jlelse.eu/android-networking-in-2019-retrofit-with-kotlins-coroutines-aefe82c4d777

我需要恢复JSON格式的数据，我收到以下错误消息:

I need to recover data in JSON format, I get the following error message :

com.squareup.moshi.JsonDataException: Expected BEGIN_OBJECT but was BEGIN_ARRAY at path $*

我看了这个答案，但是我不知道如何使它适应我的代码:

I looked at this answer but I don't know how to adapt it to my code : Retrofit Expected BEGIN_OBJECT but was BEGIN_ARRAY

这是我的界面

interface LocationService {
    @GET("locations?countryid=fr")
    fun getLocationList() : Deferred<Response<LocationResponse>>
}

LocationResponse

data class LocationResponse (val results : List<Location>)

位置模型

data class Location (
    @field:Json(name = "id") val id : String,
    @field:Json(name = "category") val category : String,
    @field:Json(name = "label") val label : String,
    @field:Json(name = "value") val value : String
)

JSON就是这样

[
  {
    "id":"city_39522",
    "category":"Villes",
    "label":"Parisot (81310)",
    "value":null
 },
 {
   "id":"city_36661",
   "category":"Villes",
   "label":"Paris 9ème (75009)",
   "value":null
 },
 {
   "id":"city_39743",
   "category":"Villes",
   "label":"Parisot (82160)",
   "value":null
 }
]

我已经有了列表，看不到如何纠正错误?

I'm already getting a list, I don't see how to correct the error ?

推荐答案

您必须将界面更新为:

interface LocationService {
    @GET("locations?countryid=fr")
    fun getLocationList() : Deferred<Response<List<Location>>>
}

此外，您不需要 LocationResponse 类并删除以下代码:

Also you don't need LocationResponse class and remove the below code:

data class LocationResponse (val results : List<Location>)

您期望得到响应并按如下方式对其进行解析:

{
  "results": [
    { .. }
  ]
}

但是实际响应是这样的:

 [
    { .. }
  ]

该错误说明您期望在根目录找到对象，但是实际的json数据是array，因此您必须将其更改为array.

The error explains that you are expecting object at the root but actual json data is array, so you have to change it to array.

这篇关于如何使用延期响应解决JSON改装错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！