MainActivity.java

package cn.zhaiyifan.github.ui;

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.NavigationView;
import android.support.design.widget.Snackbar;
import android.support.v4.app.Fragment;
import android.support.v4.view.GravityCompat;
import android.support.v4.view.PagerAdapter;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBar;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Toast;

import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;

import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;

import java.util.ArrayList;
import java.util.List;

import cn.zhaiyifan.github.R;
import cn.zhaiyifan.github.ui.base.TabPagerActivity;
import roboguice.inject.ContentView;
import roboguice.inject.InjectView;

@ContentView(R.layout.activity_main)
public class MainActivity extends TabPagerActivity {

    @InjectView(R.id.nv_main_navigation)
    NavigationView navigationView;

    @InjectView(R.id.dl_main_drawer)
    DrawerLayout mDrawerLayout;

    @InjectView(R.id.fab)
    FloatingActionButton fab;

    @Override
    protected PagerAdapter createAdapter() {
        List<String> titles = new ArrayList<>();
        titles.add("Page One");
        titles.add("Page Two");
        titles.add("Page Three");
        List<Fragment> fragments = new ArrayList<>();
        fragments.add(new TrendingListFragment());
        fragments.add(new TrendingListFragment());
        fragments.add(new TrendingListFragment());

        return new PagerFragmentAdapter(getSupportFragmentManager(), fragments, titles);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        initDrawerContent(navigationView);

        final ActionBar actionBar = getSupportActionBar();
        if (actionBar != null) {
            actionBar.setHomeAsUpIndicator(R.drawable.ic_menu);
            actionBar.setDisplayHomeAsUpEnabled(true);
        }

        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Snackbar comes out", Snackbar.LENGTH_LONG)
                        .setAction("Action", new View.OnClickListener() {
                            @Override
                            public void onClick(View v) {
                                Toast.makeText(
                                        MainActivity.this,
                                        "Toast comes out",
                                        Toast.LENGTH_SHORT).show();
                            }
                        }).show();
            }
        });

        RequestQueue mQueue = Volley.newRequestQueue(this);
        StringRequest stringRequest = new StringRequest("https://github.com/trending",
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {
                        Document doc = Jsoup.parse(response);
                        Element languageFilterListElement = doc.select(".language-filter-list").first();
                        languageFilterListElement.select(".selected").first();

                        // language list link and language text
                        for (Element languageElement : languageFilterListElement.children()) {
                            String linkHref = languageElement.getElementsByTag("a").attr("href");
                            String linkText = languageElement.text();
                            Log.d("TAG", languageElement.toString());
                        }
                    }
                }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                Log.e("TAG", error.getMessage(), error);
            }
        });
        mQueue.add(stringRequest);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.action_settings:
                return true;
            case android.R.id.home:
                mDrawerLayout.openDrawer(GravityCompat.START);
                return true;
        }

        return super.onOptionsItemSelected(item);
    }

    private void initDrawerContent(NavigationView navigationView) {
        navigationView.setNavigationItemSelectedListener(
                new NavigationView.OnNavigationItemSelectedListener() {
                    @Override
                    public boolean onNavigationItemSelected(MenuItem menuItem) {
                        menuItem.setChecked(true);
                        mDrawerLayout.closeDrawers();
                        return true;
                    }
                });
    }
}