Android studio error: element value constant expression

Question

i am trying to set a value of @GET if i put direct value my API call work fine but if i trying to get that value from other class it giving me error element value must be a constant expression

API http://49.12.80.197/Vokka/getclientbalance.do?pin=923338875585

if i write @GET("getclientbalance.do") API Call works fine

any solution for it >?

import okhttp3.OkHttpClient;
import okhttp3.logging.HttpLoggingInterceptor;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;


public class ApiClient {


    public static String BASE_URL = "http://49.12.80.197/Vokka/";
    public static String balance = "getclientbalance.do";
   

ApiInterface

import com.google.gson.JsonElement;

import retrofit2.Call;
import retrofit2.http.GET;
import retrofit2.http.Query;
import retrofit2.http.Url;

import static com.kkdialer.voip.ApiClient.balance;

public interface ApiInterface {

    @GET(value = balance)
    Call<JsonElement> getclientbalance(@Query("pin") String mobileNo);

}

error: element value must be a constant expression @GET(value = balance)

Answer 1

What you're trying to achieve is a dynamic path for a request.

To cater that, @Path annotation has been provided by Retrofit, you can read more about it here .

Use it as:

@GET("{path}")
Call<JsonElement> getclientbalance(
    @Query("pin") String mobileNo,
    @Path("path") String yourPath
);

The purpose of @Path is to provide dynamic request URLs. For example, a separate request URL based on user's username.

It, also, has the functionality to encode or not encode the URLs, read the link provided above to know more.