ThreeQieHuan

public class ChildFragment1 extends Fragment{    private String titleUrl = "https://www.toutiao.com/hot_words/";    private ImageView iv;    private TextView tv;    ArrayList<String> titleList = new ArrayList<>();    int flag = 0;    Handler  handler = new Handler(){        @Override        public void handleMessage(Message msg) {            super.handleMessage(msg);            int what = msg.what;            if (what ==1 ){                if(titleList !=null){                   int position = flag%titleList.size();                    tv.setText(titleList.get(position));                }                flag++;                sendMsg();            }        }    };    //只写加载布局和找到控件    @Nullable    @Override    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {        View view = inflater.inflate(R.layout.tain, null);        iv = view.findViewById(R.id.iv);        tv = view.findViewById(R.id.tv);        return view;    }    /**     * 写fragment的逻辑；     * @param view     * @param savedInstanceState     */    @Override    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {        super.onViewCreated(view, savedInstanceState);        initTitlData();    }    /**     * 获取头条内容数据     */    private void initTitlData() {        new MTitleAsyncTask().execute(titleUrl);    }    private class MTitleAsyncTask extends AsyncTask<String,Void,String>{        @Override        protected String doInBackground(String... strings) {            String netJson = NetUtil.getNetJson(strings[0]);            return netJson;        }        @Override        protected void onPostExecute(String s) {            super.onPostExecute(s);            try {                JSONArray jsonArray = new JSONArray(s);                for (int i = 0; i < jsonArray.length(); i++) {                    Log.e("wzq", "onPostExecute: "+jsonArray.getString(i) );                    titleList.add(jsonArray.getString(i));                }                sendMsg();            } catch (JSONException e) {                e.printStackTrace();            }        }    }    private void sendMsg() {        //延迟发送消息;        handler.sendEmptyMessageDelayed(1,3000);    }}