Connection请求数据

最新推荐文章于 2023-08-09 09:17:10 发布

污鸦

最新推荐文章于 2023-08-09 09:17:10 发布

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CC 4.0 BY-SA版权

本文链接：https://blog.youkuaiyun.com/ysc332606387/article/details/78232127

本文介绍了一种使用AsyncTask从远程服务器获取JSON数据并解析到ListView的方法。通过创建URL对象并建立HTTP连接，该方法能够异步地获取数据，避免了阻塞UI线程。在后台线程中读取数据后，再将其解析为List对象并适配到ListView上。

//listview数据源

List<Bean.ResultBean.ListBean> list=new ArrayList<>();

//在onCreat方法调用内部类，实例化对象启动后置参数为接口网址

MyTask task=new MyTask();
task.execute("http://v.juhe.cn/weixin/query?key=88f7bbc507e3ecacfaeab2b47dd8936f&ps=30");

//内部类

class MyTask extends AsyncTask<String,Void,String>{
        String resultStr;
        @Override
        protected String doInBackground(String... params) {
            try {
                //创建URL对象
                URL url=new URL(params[0]);
                //打开连接
                HttpURLConnection connection= (HttpURLConnection) url.openConnection();
                //设置
                connection.setRequestMethod("GET");
                connection.setConnectTimeout(5000);
                connection.setReadTimeout(5000);
                //得到响应码
                int code=connection.getResponseCode();
                if (code==200){
                    //得到结果
                    InputStream inputStream=connection.getInputStream();
                    resultStr=streamToString(inputStream);
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return resultStr;
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);

            Gson gson=new Gson();
            Bean bean=gson.fromJson(s, Bean.class);
            Bean.ResultBean result=bean.getResult();
            list=result.getList();
            Log.i("nxx",list.toString());
            lv.setAdapter(new MyAdapter());
        }
    }

    public String streamToString(InputStream stream) {
        StringBuilder builder = new StringBuilder();
        try {
            BufferedReader br = new BufferedReader(new InputStreamReader(stream, "utf-8"));
            String con;
            while ((con = br.readLine()) != null) {
                builder.append(con);
            }

        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return builder.toString();
    }