Stackoverflow در اندروید

compile 'com.squareup.retrofit:retrofit:2.0.0-beta2'
compile 'com.squareup.retrofit:converter-gson:2.0.0-beta2'

package android.vogella.com.retrofitstackoverflow;
// This is used to map the JSON keys to the object by GSON
public class Question {
String title;
String link;
@Override
public String toString() {
return(title);
}
}
package android.vogella.com.retrofitstackoverflow;
import java.util.List;
public class StackOverflowQuestions {
List<Question> items;
}

package com.vogella.android.retrofitstackoverflow;
import retrofit.Callback;
import retrofit.http.GET;
import retrofit.http.Query;
import retrofit.Call;
public interface StackOverflowAPI {
@GET("/2.2/questions?order=desc&sort=creation&site=stackoverflow")
Call<StackOverflowQuestions> loadQuestions(@Query("tagged") String tags);
}

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:id="@+id/menu_load"
android:title="Load" />
</menu>

package com.vogella.android.retrofitstackoverflow;
import android.app.Activity;
import android.app.ListActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.Window;
import android.widget.ArrayAdapter;
import android.widget.Toast;
import java.util.ArrayList;
import retrofit.Call;
import retrofit.Callback;
import retrofit.GsonConverterFactory;
import retrofit.Response;
import retrofit.Retrofit;
public class MainActivity extends ListActivity implements Callback<StackOverflowQuestions> {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
requestWindowFeature(Window.FEATURE_PROGRESS);
ArrayAdapter<Question> arrayAdapter =
new ArrayAdapter<Question>(this,
android.R.layout.simple_list_item_1,
android.R.id.text1,
new ArrayList<Question>());
setListAdapter(arrayAdapter);
setProgressBarIndeterminateVisibility(true);
setProgressBarVisibility(true);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main_menu, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
setProgressBarIndeterminateVisibility(true);
Retrofit retrofit = new Retrofit.Builder()
.baseUrl("https://api.stackexchange.com")
 
.addConverterFactory(GsonConverterFactory.create())
.build();
// prepare call in Retrofit ۲٫۰
StackOverflowAPI stackOverflowAPI = retrofit.create(StackOverflowAPI.class);
Call<StackOverflowQuestions> call = stackOverflowAPI.loadQuestions("android");
//asynchronous call
call.enqueue(this);
// synchronous call would be with execute, in this case you
// would have to perform this outside the main thread
// call.execute()
// to cancel a running request
// call.cancel();
// calls can only be used once but you can easily clone them
//Call<StackOverflowQuestions> c = call.clone();
//c.enqueue(this);
return true;
}
@Override
public void onResponse(Response<StackOverflowQuestions> response, Retrofit retrofit) {
setProgressBarIndeterminateVisibility(false);
ArrayAdapter<Question> adapter = (ArrayAdapter<Question>) getListAdapter();
adapter.clear();
adapter.addAll(response.body().items);
}
@Override
public void onFailure(Throwable t) {
Toast.makeText(MainActivity.this, t.getLocalizedMessage(), Toast.LENGTH_SHORT).show();
}
}