MainActivity.java

package com.tutosandroidfrance.RetrofitSample;

import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.support.v7.app.ActionBarActivity;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import retrofit.Callback;
import retrofit.RestAdapter;
import retrofit.RetrofitError;
import retrofit.android.AndroidLog;
import retrofit.client.Response;
import rx.Observable;
import rx.android.schedulers.AndroidSchedulers;
import rx.functions.Action1;
import rx.functions.Func1;
import rx.functions.Func2;
import rx.schedulers.Schedulers;


public class MainActivity extends ActionBarActivity {

    GithubService githubService;
    TextView textView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        textView = (TextView) findViewById(R.id.textView);

        githubService = new RestAdapter.Builder()
                .setEndpoint(GithubService.ENDPOINT)
                .setLog(new AndroidLog("retrofit"))
                .setLogLevel(RestAdapter.LogLevel.FULL)
                .build()
                .create(GithubService.class);

        getListRepos();
    }

    private void getListRepos() {
        githubService.listRepos("florent37")
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())

                        //on commence par couper notre observable de List<Repo> en observable de Repo
                .flatMap(new Func1<List<Repo>, Observable<Repo>>() {
                    @Override
                    public Observable<Repo> call(List<Repo> repos) {
                        return Observable.from(repos);
                    }
                })
                        //afin de récupérer le nom de chaque repo, nous aurons donc des Observable<String>
                .map(new Func1<Repo, String>() {
                    @Override
                    public String call(Repo repo) {
                        return repo.getName();
                    }
                })

                        //on trie nos Observable<String>
                .toSortedList(new Func2<String, String, Integer>() {
                    @Override
                    public Integer call(String s, String s2) {
                        return s.compareTo(s2);
                    }
                })

                        //on coupe l'observable de List<String> en Observable<String>
                .flatMap(new Func1<List<String>, Observable<String>>() {
                    @Override
                    public Observable<String> call(List<String> strings) {
                        return Observable.from(strings);
                    }
                })
                        //afin d'accéder à la méthode reduce, permettant de réduire nos noms, de la forme nom1 \n nom2
                .reduce(new Func2<String, String, String>() {
                    @Override
                    public String call(String s, String s2) {
                        return s + "\n" + s2;
                    }
                })

                        //on obtient à la fin un String contenant la liste de nos noms de repo, que l'on va afficher
                .subscribe(new Action1<String>() {
                    @Override
                    public void call(String s) {
                        textView.setText(s);
                    }
                });

    }

    private void getListReposWithoutRX() {
        githubService.listRepos("florent37", new Callback<List<Repo>>() {
            @Override
            public void success(List<Repo> repos, Response response) {

                //.subscribeOn(Schedulers.io())
                new Handler().post(new Runnable() {
                    @Override
                    public void run() {

                        //.map > String
                        List<String> reposNames = new ArrayList<String>();
                        for (Repo repo : repos)
                            reposNames.add(repo.getName());

                        //.toSortedList
                        Collections.sort(reposNames, new Comparator<String>() {
                            @Override
                            public int compare(String s, String s2) {
                                return s.compareTo(s2);
                            }
                        });

                        //.reduce
                        final StringBuffer concat = new StringBuffer();
                        for (String repoName : reposNames)
                            concat.append(repoName).append("\n");

                        //.observeOn(AndroidSchedulers.mainThread())
                        new Handler(Looper.getMainLooper()).post(new Runnable() {
                            @Override
                            public void run() {
                                textView.setText(concat);
                            }
                        });

                    }
                });

            }

            @Override
            public void failure(RetrofitError error) {

            }
        });
    }
}