android Activity怎么改成Fragment

原来是activity 我改成了Fragmentactivity，在下面的添加到fragmentlist中时直接报错 程序结束

    private List<Fragment> fragmentlist;
        private ZBarDemoActivity fragment1;
        private Fragment2 fragment2;

    。。。。。。
        @SuppressWarnings("unchecked")
        public void initDatasViewPager() {
            //Intent intent = new Intent(main.this,ZBarDemoActivity.class);
            fragmentlist = new ArrayList<Fragment>();
            fragment1 = new ZBarDemoActivity();//
            fragment2 = new Fragment2();//
            fragmentlist.addAll((Collection<? extends Fragment>) fragment1);显示这里错误
            fragmentlist.addAll((Collection<? extends Fragment>) fragment2);
            fragmentViewPager.setAdapter(new FragmentAdapter(getSupportFragmentManager(), fragmentlist, this));
            fragmentViewPager.setOnPageChangeListener(new MyOnPageChangeListener());
        }

http://blog.ch-wind.com/android%E7%AE%80%E5%8D%95%E7%9A%84%E5%B0%86activity%E6%94%B9%E4%B8%BAfragment/

使继承AppCompatActivity

无语了，重新创建个Fragment，讲activity的layout通过fragment加载即可

fragmentactivity 又不是fragment。。。怎么可以放进那个集合里面额，单独再写个fragment吧