Main Activity Retrofit

package com.yoesuv.demoretrofit;

import android.app.ProgressDialog;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import java.util.Arrays;
import java.util.List;

import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;

public class MainActivity extends AppCompatActivity {

    private ListView listView_tempat;
    private ArrayAdapter<String> adapter;
    private ProgressDialog pDialog;
    private String[] dataGambar;

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

        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        if(getSupportActionBar()!=null){
            getSupportActionBar().setElevation(5);
        }

        listView_tempat = (ListView) findViewById(R.id.listView_tempat);
        adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1);
        pDialog = new ProgressDialog(this);

        loadTempat();

        listView_tempat.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                Intent i = new Intent(view.getContext(), MainImage.class);
                i.putExtra(MainImage.EXTRA_NAMA,adapter.getItem(position));
                i.putExtra(MainImage.EXTRA_IMAGE, dataGambar[position]);
                startActivity(i);
            }
        });
    }


    private void loadTempat(){

        pDialog.setMessage("Please Wait...");
        pDialog.setCancelable(false);
        pDialog.setCanceledOnTouchOutside(false);
        pDialog.show();

        Retrofit retrofit = new Retrofit.Builder().baseUrl(getResources().getString(R.string.url_json))
                .addConverterFactory(GsonConverterFactory.create()).build();

        DataInterface dataInterface = retrofit.create(DataInterface.class);

        Call<List<DataTempat>> callData = dataInterface.callTempat();
        callData.enqueue(new Callback<List<DataTempat>>() {
            @Override
            public void onResponse(Call<List<DataTempat>> call, Response<List<DataTempat>> response) {
                if (response.isSuccessful()) {
                    int i = 0;
                    dataGambar = new String[response.body().size()];
                    for (DataTempat tempat : response.body()) {
                        adapter.add(tempat.getNama());
                        dataGambar[i] = tempat.getGambar();
                        i++;
                    }
                    listView_tempat.setAdapter(adapter);
                    pDialog.dismiss();
                }
            }

            @Override
            public void onFailure(Call<List<DataTempat>> call, Throwable t) {

            }
        });


    }
}