public class MainActivity extends ActionBarActivity implements NavigationDrawerCallbacks{

    private Toolbar mToolbar;
    private NavigationDrawerFragment mNavigationDrawerFragment;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mToolbar = (Toolbar) findViewById(R.id.toolbar_actionbar);
        setSupportActionBar(mToolbar);
        getSupportActionBar().setDisplayShowHomeEnabled(true);
        mNavigationDrawerFragment = (NavigationDrawerFragment) getFragmentManager().findFragmentById(R.id.fragment_drawer);
        mNavigationDrawerFragment.setup(R.id.fragment_drawer, (DrawerLayout) findViewById(R.id.drawer), mToolbar);
    mToolbar.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                if (Build.VERSION.SDK_INT >= 16) {
                    mToolbar.getViewTreeObserver().removeOnGlobalLayoutListener(this);
                } else {
                    mToolbar.getViewTreeObserver().removeGlobalOnLayoutListener(this);
                }
        mToolbar.animate().translationY(-mToolbar.getBottom()).setInterpolator(new AccelerateInterpolator()).start();
            }
        });
    }

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

    @Override
    public void onNavigationDrawerItemSelected(int position) {
        if (position == 1){
            FeedFragment Frag = new FeedFragment();
            FragmentTransaction transaction = getFragmentManager().beginTransaction();
            transaction.replace(R.id.container, Frag);
            transaction.commit();

        }else if (position == 2){
            startActivity(new Intent(this, VideoActivity.class));
        }
    }
}