fragment复用==

public class HomePage extends Fragment {    private TabLayout tabLayout;    private ViewPager viewPager;    private List<Fragment> list;    private String[] str = new String[]{"推荐", "体育", "科技", "教育", "娱乐", "财经", "股票", "旅游", "美女"};    private Button button;    private List<ChannelBean> channelBeanList;    private List<String> newslist;    private SharedPreferences sp;    private String json;    private AppCompatActivity context;    private List<String> urllist;    @Override    public void onAttach(Context context) {        super.onAttach(context);        this.context = (AppCompatActivity) context;    }    @Nullable    @Override    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {        View view = View.inflate(getActivity(), R.layout.activity_home_page, null);        tabLayout = (TabLayout) view.findViewById(R.id.tab);        viewPager = (ViewPager) view.findViewById(R.id.viewpager);        sp = context.getSharedPreferences("set", context.MODE_PRIVATE);        json = sp.getString("use", null);        initView();        button = (Button) view.findViewById(R.id.jia);        newslist = new ArrayList<>();        newslist.add("推荐");newslist.add("热点");newslist.add("北京");        newslist.add("股票");        newslist.add("社会");newslist.add("图片");newslist.add("娱乐");        newslist.add("问答");newslist.add("科技");newslist.add("汽车");        newslist.add("财经");newslist.add("军事");newslist.add("体育");        newslist.add("段子");newslist.add("美女");newslist.add("国际");        newslist.add("健康");newslist.add("小说");newslist.add("时尚");        newslist.add("旅游");newslist.add("数码");newslist.add("教育");        newslist.add("房产");newslist.add("历史");newslist.add("宠物");        newslist.add("美食");newslist.add("游戏");newslist.add("视频");        button.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View view) {                if (json == null) {                    channelBeanList = new ArrayList<ChannelBean>();                    for (int i = 0; i < newslist.size(); i++) {                        ChannelBean bean = null;                        if (i < 10) {                            bean = new ChannelBean(newslist.get(i), true);                        } else {                            bean = new ChannelBean(newslist.get(i), false);                        }                        channelBeanList.add(bean);                    }                    ChannelActivity.startChannelActivity(context, channelBeanList);                } else {                    ChannelActivity.startChannelActivity(context, json);                }            }        });        urllist = new ArrayList<>();        for (String title : str) {            urllist.add("http://wangyi.butterfly.mopaasapp.com/news/api?type=war&limit=10&page=");            urllist.add("http://wangyi.butterfly.mopaasapp.com/news/api?type=sport&limit=10&page=");            urllist.add("http://wangyi.butterfly.mopaasapp.com/news/api?type=tech&limit=10&page=");            urllist.add("http://wangyi.butterfly.mopaasapp.com/news/api?type=edu&limit=10&page=");            urllist.add("http://wangyi.butterfly.mopaasapp.com/news/api?type=ent&limit=10&page=");            urllist.add("http://wangyi.butterfly.mopaasapp.com/news/api?type=money&limit=10&page=");            urllist.add("http://wangyi.butterfly.mopaasapp.com/news/api?type=gupiao&limit=10&page=");            urllist.add("http://wangyi.butterfly.mopaasapp.com/news/api?type=travel&limit=10&page=");            urllist.add("http://wangyi.butterfly.mopaasapp.com/news/api?type=lady&limit=10&page=");        }        return view;    }    private void initView() {        tabLayout.setTabMode(TabLayout.MODE_SCROLLABLE);        MyAdapter adapter = new MyAdapter(getActivity().getSupportFragmentManager());        viewPager.setAdapter(adapter);        tabLayout.setupWithViewPager(viewPager);    }    class MyAdapter extends FragmentPagerAdapter {        public MyAdapter(FragmentManager fm) {            super(fm);        }        @Override        public Fragment getItem(int position) {            Recommend rec = new Recommend();            Bundle bundle = new Bundle();            bundle.putString("urlconnect", urllist.get(position));            rec.setArguments(bundle);            return rec;        }        @Override        public int getCount() {            return str.length;        }        @Override        public CharSequence getPageTitle(int position) {            return str[position];        }    }}