Android应用中怎么实现一个FragmentPagerAdapter适配器

public class MyFragmentPagerAdapter extends FragmentPagerAdapter {  private List<Fragment> list;   public MyFragmentPagerAdapter(FragmentManager fm, List<Fragment> list) {     super(fm);     this.list = list;  }  //返回了当前要滑动的View的个数   @Override   public int getCount() {     return list.size();   }   //在getItem(int arg0)中，根据传来的参数arg0，来返回当前要显示的fragment  @Override   public Fragment getItem(int arg0) {     return list.get(arg0);   }}