查找数据库数据,展示在ListView中

listview = view.findViewById(R.id.listview2);
        Dao dao=new Dao(getActivity());
        List<Json.DataBean> list=new ArrayList<Json.DataBean>();
        Cursor query =dao.query("person", null, null, null, null, null,null);
        if (query.moveToFirst()) {
            do{
                String url = query.getString(query.getColumnIndex("url"));
                String title = query.getString(query.getColumnIndex("title"));
                String summary = query.getString(query.getColumnIndex("summary"));
                Json.DataBean bean=new Json.DataBean();
                bean.setNews_id(null);
                bean.setNews_summary(summary);
                bean.setNews_title(title);
                bean.setPic_url(url);
                list.add(bean);
            }while (query.moveToNext());
        }

    Myadapter myadapter=new Myadapter(getActivity(),list);
    listview.setAdapter(myadapter);