請求網絡數據並listview優化展示

public class Child1Fragment extends Fragment {

    private ListView lv;
    private ArrayList<Product.DataBean> list = new ArrayList<>();

    public String urlString = "http://api.expoon.com/AppNews/getNewsList/type/1/p/1";
    Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            mAdapter.notifyDataSetChanged();


        }
    };
    private MAdapter mAdapter;


    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = View.inflate(getActivity(), R.layout.fragment_child_pull, null);
        lv = (ListView) view.findViewById(R.id.lv);
        return view;
    }

    @Override
    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        mAdapter = new MAdapter();
        lv.setAdapter(mAdapter);
        initData();
        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
                    @Override
                    public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                        Intent intent = new Intent(getActivity(), SecondActivity.class);
                        Bundle bundle = new Bundle();
                        bundle.putSerializable("list", list);
                        intent.putExtra("bundle", bundle);
                        startActivity(intent);
                    }
                });

    }

    /**
     * 請求服務器數據；
     */
    private void initData() {
        new Thread() {
            @Override
            public void run() {
                super.run();
                if (NetState.getNetType(getActivity()) == 1 || NetState.getNetType(getActivity()) == 0) {
                    String netJson = NetUtil.getNetJson(urlString);
                    Gson gson = new Gson();
                    Product product = gson.fromJson(netJson, Product.class);
                    List<Product.DataBean> data = product.getData(); //
                    //把請求到的數據放入自己的大集合中；
                    list.addAll(data);
                    handler.sendEmptyMessage(0);
                } else {
//                    Toast.makeText(getActivity(), "無網絡", Toast.LENGTH_SHORT).show();
                    Log.e("wzq","無網絡");
                }


            }
        }.start();
    }

    private class MAdapter extends BaseAdapter {

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

        @Override
        public Object getItem(int i) {
            return list.get(i);
        }

        @Override
        public long getItemId(int i) {
            return i;
        }

        @Override
        public View getView(int i, View view, ViewGroup viewGroup) {
            ViewHolder holder = null;
            if (view == null) {
                holder = new ViewHolder();
                view = View.inflate((Context) getActivity(), R.layout.item1, null);
                view.setTag(holder);
                holder.tv_name = view.findViewById(R.id.tv_name);
                holder.iv = view.findViewById(R.id.iv);
            } else {
                holder = (ViewHolder) view.getTag();
            }
            holder.tv_name.setText(list.get(i).getNews_title());
            holder.iv.setImageResource(R.mipmap.ic_launcher);

            return view;
        }

    }

    class ViewHolder {
        TextView tv_name;
        ImageView iv;


    }