如何在android中启动时仅显示三个选项卡项

<android.support.design.widget.TabLayout
    android:id="@+id/tab_layout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:tabMode="fixed"
    app:tabGravity="fill"/>

<android.support.v4.view.ViewPager
    android:id="@+id/view_pager"
    android:layout_width="match_parent"
    android:layout_height="match_parent"/>

public class TabAdapter extends FragmentPagerAdapter {
    private List<Fragment> fragments = new ArrayList<>();
    private List<String> titles = new ArrayList<>();

    public TabAdapter(FragmentManager fm) {
        super(fm);
    }

    public void addFragment(Fragment fragment, String title) {
        fragments.add(fragment);
        titles.add(title);
    }

    @Override
    public Fragment getItem(int position) {
        return fragments.get(position);
    }

    @Override
    public int getCount() {
        return fragments.size();
    }

    @Override
    public CharSequence getPageTitle(int position) {
        return titles.get(position);
    }
}

TabLayout tabLayout = findViewById(R.id.tab_layout);
ViewPager viewPager = findViewById(R.id.view_pager);

TabAdapter tabAdapter = new TabAdapter(getSupportFragmentManager());
tabAdapter.addFragment(new Fragment1(), "选项卡1");
tabAdapter.addFragment(new Fragment2(), "选项卡2");
tabAdapter.addFragment(new Fragment3(), "选项卡3");

viewPager.setAdapter(tabAdapter);
tabLayout.setupWithViewPager(viewPager);