Retrofit = Manipulating the Sponse

Question

Well, I’m asking for more help from friends so really, I’m not getting the dynamics.

Following tutorials and explanations here from the forum I am TRYING to use the Retrofit but it’s not working.

I got the following JSON down below,

{
  "clientes":
     [
        {"idClientesT":"1","tipo":"s","nome":"Carlos"},
        {"idClientesT":"2","tipo":"s","nome":"Rogério"}
     ]
} 

That I get when I access URL down below,

http://hotplateprensas.com.br/ws/clientest.php

I’m wearing it like this:

Interface:

package carcleo.com.radiosingular.classes;

import java.util.List;

import retrofit2.Call;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;
import retrofit2.http.GET;
import retrofit2.http.Path;

public interface ClientesI {
    @GET("clientest.php")
    Call<List<Clientes>> listClientes();
}

Activity:

package carcleo.com.radiosingular;

import android.os.Build;
import android.support.annotation.RequiresApi;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import java.util.List;

import carcleo.com.radiosingular.classes.Clientes;
import carcleo.com.radiosingular.classes.ClientesI;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;

public class retrofit extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.retrofit);

        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl("http://www.hotplateprensas.com.br/ws/")
                .addConverterFactory(GsonConverterFactory.create())
                .build();

        ClientesI service = retrofit.create(ClientesI.class);


        service.listClientes().enqueue(new Callback<List<Clientes>>() {
            @Override public void onResponse(Call<List<Clientes>> call, Response<List<Clientes>> response) {

                int code = response.code();
                if (code == 200) {
                    for (Clientes cli : response.body()) {
                        Toast.makeText(getBaseContext(), "Id do cliente: " + cli.getIdClientesT(), Toast.LENGTH_LONG).show();
                        Toast.makeText(getBaseContext(), "Tipo do cliente: " + cli.getTipo(), Toast.LENGTH_LONG).show();
                        Toast.makeText(getBaseContext(), "Nome do cliente: " + cli.getNome(), Toast.LENGTH_LONG).show();
                    }
                } else {
                    Toast.makeText(getBaseContext(), "Falha: " + String.valueOf(code), Toast.LENGTH_LONG).show();
                }

            }

            @Override public void onFailure(Call<List<Clientes>> call, Throwable t) {
                Log.v("Errado: ", t.toString());
                Toast.makeText(getBaseContext(), t.getMessage(), Toast.LENGTH_LONG).show();
            }
        });

   }

}

The class of Customers:

package carcleo.com.radiosingular.classes;

public class Clientes {
    private int idClientesT;
    private String tipo;
    private String nome;

    public Clientes(int idClientesT, String tipo, String nome) {
        this.idClientesT = idClientesT;
        this.tipo = tipo;
        this.nome = nome;
    }

    public int getIdClientesT() {
        return idClientesT;
    }

    public String getTipo() {
        return tipo;
    }

    public String getNome() {
        return nome;
    }
}

The goal is to walk the array JSON obtained by access to webservice and return a list of objects of class Customers.

Error only occurs at runtime.

But for me the error is of encoding same. Of logic.

Note: I NAY can receive

code == 200

You’re walking right into this block:

@Override public void onFailure(Call<List<Clientes>> call, Throwable t) {
   Log.v("Errado: ", t.toString());
   Toast.makeText(getBaseContext(), t.getMessage(), Toast.LENGTH_LONG).show();
}

But I cannot manipulate the return (Sponse)

Console error RUN:

W/art: Before Android 4.1, method int android.support.v7.widget.DropDownListView.lookForSelectablePosition(int, boolean) would have incorrectly overridden the package-private method in android.widget.ListView
D/OpenGLRenderer: endAllActiveAnimators on 0x9a465680 (RippleDrawable) with handle 0x9a5fd370
V/Errado:: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was BEGIN_OBJECT at line 1 column 2 path $

Can someone help me?

Answer 1

Class returned in your service method must match the JSON representation the API returns.

Create a class that represents JSON:

import java.util.List;

class ClientesResponse {

  private List<Clientes> clientes;

  public ClientesResponse(List<Clientes> clientes) {
    this.clientes = clientes;
  }

  public List<Clientes> getClientes() {
    return clientes;
  }

  public void setClientes(List<Clientes> clientes) {
    this.clientes = clientes;
  }
}

And use it on the return of the Retrofit:

Call<ClientesResponse> listClientes();