RetrofitPostExample.java

    private void experimentPostQuestion(){
        OkHttpClient.Builder httpClient = new OkHttpClient.Builder();
        httpClient.addInterceptor(new Interceptor() {
            @Override
            public okhttp3.Response intercept(Chain chain) throws IOException {
                String userName = "admin";
                String password = "pass";

                String base64EncodedCredentials = "Basic " + Base64.encodeToString(
                        (userName + ":" + password).getBytes(),
                        Base64.NO_WRAP);

                okhttp3.Request original = chain.request();

                okhttp3.Request.Builder requestBuilder = original.newBuilder()
                        .header("Authorization", base64EncodedCredentials)
                .header("Accept", "application/json")
                .method(original.method(), original.body());

                okhttp3.Request request = requestBuilder.build();
                return chain.proceed(request);
            }
        });
        OkHttpClient client = httpClient.build();

        final String BASE_URL = "http://yourapi.com/api/";

        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(BASE_URL)
                .addConverterFactory(GsonConverterFactory.create())
                .client(client)
                .build();

        APIService apiService = retrofit.create(APIService.class);
        LocationBody locationBody = new LocationBody(-6.92f, 107.61f);
        Call<LocationID> locationIDCall = apiService.loadLocationWithoutHeader(locationBody);
        locationIDCall.enqueue(new Callback<LocationID>() {
            @Override
            public void onResponse(Call<LocationID> call, retrofit2.Response<LocationID> response) {
                Log.d("asdf", "loc id" + response.body().getResult().getLOCID());
                Log.d("asdf", "loc name " + response.body().getResult().getLOCNAME());

            }

            @Override
            public void onFailure(Call<LocationID> call, Throwable t) {
                Log.d("asdf", "failure " + t.getMessage());

            }
        });

    }
    
        private void callPostQuestion(){
        final String BASE_URL = "http://yourapi.com/api/";

        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(BASE_URL)
                .addConverterFactory(GsonConverterFactory.create())
                .build();

        APIService apiService = retrofit.create(APIService.class);
        LocationBody locationBody = new LocationBody(-6.92f, 107.61f);
        Call<LocationID> locationIDCall = apiService.loadLocation(locationBody);
        locationIDCall.enqueue(new Callback<LocationID>() {
            @Override
            public void onResponse(Call<LocationID> call, retrofit2.Response<LocationID> response) {
                Log.d("asdf", "loc id" + response.body().getResult().getLOCID());
                Log.d("asdf", "loc name " + response.body().getResult().getLOCNAME());

            }

            @Override
            public void onFailure(Call<LocationID> call, Throwable t) {
                Log.d("asdf", "failure " + t.getMessage());

            }
        });
    }