如何在MainActivity选项卡布局中添加导航抽屉？

Question

请教我如何在此活动中添加导航抽屉。

MainActivity （标签布局）

public class MainActivity extends AppCompatActivity {

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

        TabLayout tabLayout = (TabLayout) findViewById(R.id.tab_layout);
        assert tabLayout != null;
        tabLayout.addTab(tabLayout.newTab().setText(R.string.welcome));
        tabLayout.addTab(tabLayout.newTab().setText(R.string.venue));
        tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);

        final ViewPager viewPager = (ViewPager) findViewById(R.id.pager);
        final PagerAdapter adapter = new FragmentStatePagerAdapter(getSupportFragmentManager()) {

            @Override
            public Fragment getItem(int position) {
                switch (position) {
                    case 0:
                        return new WelcomeFragment();
                    case 1:
                        return new pptp();
                }
                return null;
            }

            @Override
            public int getCount() {
                return 2;
            }
        };
        assert viewPager != null;
        viewPager.setAdapter(adapter);
        viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
        tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
            @Override
            public void onTabSelected(TabLayout.Tab tab) {
                viewPager.setCurrentItem(tab.getPosition());
            }

            @Override
            public void onTabUnselected(TabLayout.Tab tab) {

            }

            @Override
            public void onTabReselected(TabLayout.Tab tab) {

            }
        });
    }

    public void refreshNow() {
        finish();
        overridePendingTransition(0,0);
        startActivity(getIntent());
        overridePendingTransition(0,0);

    }

}

教我如何添加导航抽屉，这对我有很大帮助。 提前感谢那些愿意帮助我的人。