如何动态更新Viewpager中的片段？

public class MyPagerAdapter extends FragmentPagerAdapter {
    private List<Fragment> fragments;

    public MyPagerAdapter(FragmentManager fm, List<Fragment> fragments) {
        super(fm);
        this.fragments = fragments;
    }

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

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

    @Override
    public int getItemPosition(Object object) {
        return POSITION_NONE;
    }
}

MyPagerAdapter adapter = new MyPagerAdapter(getSupportFragmentManager(), fragments);
viewPager.setAdapter(adapter);
adapter.notifyDataSetChanged();