How to parse a JSON response with retrofit

Question

So, I have given an API that returns this on a POST call

{
 "JHK":"One piece",
 "LKJ":"Two pieces",
 "OEN":"Three pieces"
}

And since this is a list but is not good formated from the backend I dont know how to get it from Android, this is what I have tried

WebService

@POST("get_user_codes.php")
suspend fun getUserCodesByMemberId(@Body member_id:String): CodesResponse

CodesResponse

data class CodesResponse(val data: List<Code>)
data class Code(val code_id:String,val name:String)

Repository

suspend fun getUserCodes(memberId:String):Result<CodesResponse>{
        return Result.Success(webService.getUserCodesByMemberId(memberId))
    }

But his is outping Null as the response, I really dont know how to bring those different objects that are supposed to be an array of object but instead they are all inside one object

Any idea ?

API INPUTS

member_id    as text string

Example of input:
{ "member_id": "1"}

API OUTPUTS

code_id: as a String

name: as a String

 {
     "JHK":"One piece",
     "LKJ":"Two pieces",
     "OEN":"Three pieces"
    }

EDIT

the values can be more than those 3 I posted, it depends on how many the response returns

Answer 1

suppose you have response like that

 String json = {
                "JHK":"One piece",
                "LKJ":"Two pieces",
                "OEN":"Three pieces"
}

then you can get a list of values ignoring keys like:

    ArrayList<String> arr = new ArrayList<>();
    try {

        JSONObject response = new JSONObject(json);
        Iterator keys = response.keys();

        while (keys.hasNext()) {
            // loop to get the dynamic key
            String currentKey = (String) keys.next();

            // get the value of the dynamic key
             String value = response.getJSONObject(currentKey).toString();
            arr.add(value);
        }


    } catch (Throwable t) {
        Log.e("My App", "Could not parse malformed JSON: \"" + json + "\"");
    }

Answer 2

Are field names JHK LKJ OEN always the same? You said there can be more than 3, what will be the other name when it's more than 3?

AbdelraZek posted a great solution to this problem: https://stackoverflow.com/a/64246981/14259754

My version of it in Kotlin with Retrofit in mind:

Retrofit:

// Here we use ScalarsConverter to be able to return String as a response.
Retrofit.Builder()
.baseUrl("http://YourURL")
.addConverterFactory(ScalarsConverterFactory.create())
.build()
.create(YourInterfaceClass::class.java)


// Then you can proceed to your POST function
suspend fun getUserCodesByMemberId(@Body member_id:String): String

// I suggest using Response<String> so you can check the response code and process it if needed.

Then, wherever you need, just do the following:

val response = getUserCodesByMemberId

val json = JSONObject(response.body()!!) 
val array = mutableListOf<String>()

val keys: Iterator<String> = json.keys()
while (keys.hasNext()) {
  val key = keys.next()
  array.add(json[key].toString())
}

This way you can work with Json response that is unknown to you.