HttpURLConnection—_Post请求

 private Handler handler = new Handler(){
        @Override
        public void handleMessage(Message msg) {
            if (msg.what == 0){
                DataDataBean dataDataBean = (DataDataBean) msg.obj;

                final List<DataDataBean.ResultBean.DataBean> list = dataDataBean.getResult().getData();

                //设置适配器
                MyAdapter myAdapter = new MyAdapter(MainActivity.this, list);
                listView.setAdapter(myAdapter);

                /**
                 * 条目的点击事件
                 */
                listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
                    @Override
                    public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                        //跳转.....url路径传过去
                        Intent intent = new Intent(MainActivity.this,SecondActivity.class);

                        intent.putExtra("url",list.get(i).getUrl());

                        startActivity(intent);
                    }
                });

            }
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        listView = (ListView) findViewById(R.id.list_view);

    }

    /**
     * 点击事件中去获取网络上的json数据
     *
     * httpUrlConnection请求的post方式
     *
     * type=top&key=597b4f9dcb50e051fd725a9ec54d6653
     *
     * get方式的地址:http://v.juhe.cn/toutiao/index?type=top&key=597b4f9dcb50e051fd725a9ec54d6653
     */
    public void getDataFromNet(View view){
        //访问之前先判断一下网络状态
        if (NetWorkUtil.isConn(MainActivity.this)){
            new Thread(){
                @Override
                public void run() {
                    //获取数据的地址
                    String path = "http://v.juhe.cn/toutiao/index";

                    try {
                        URL url = new URL(path);

                        //打开连接
                        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                        //设置
                        connection.setRequestMethod("POST");
                        connection.setReadTimeout(5000);
                        connection.setConnectTimeout(5000);

                        //设置请求内容的类型
                        connection.setRequestProperty("Content-Type","application/x-www-form-urlencoded");

                        //设置可以向外输出...因为post方式的时候参数是以流的形式写给服务器,所以设置向外输出
                        connection.setDoOutput(true);

                        //参数
                        String params = "type=top&key=597b4f9dcb50e051fd725a9ec54d6653";
                        //把参数以流的形式写给服务器
                        connection.getOutputStream().write(params.getBytes());//代码到这个位置,,,参数写给服务器

                        //获取
                        int responseCode = connection.getResponseCode();
                        if (responseCode == 200){
                            //获取到服务器返回的输入字节流....装的是json格式的数据
                            InputStream inputStream = connection.getInputStream();

                            //把字节流转成字符串
                            String json = streamToString(inputStream,"utf-8");

                            //解析获取到的json格式的字符串
                            Gson gson = new Gson();

                            //生成变量...alt+enter.....此时所有的数据都装到bean里面了
                            DataDataBean dataDataBean = gson.fromJson(json, DataDataBean.class);


                            //由于处在子线程,不能设置适配器,,,所以把bean发送到主线程
                            Message message = Message.obtain();
                            message.what = 0;
                            message.obj = dataDataBean;
                            handler.sendMessage(message);
                        }


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

                }
            }.start();
        }else {
            //没有网络的时候弹窗提示
            NetWorkUtil.showNoNetWorkDlg(MainActivity.this);
        }






    }

    /**
     * 把字节流转换为字符串
     * @param inputStream
     * @param
     * @return
     */
    private String streamToString(InputStream inputStream, String charset) {

        //1.将输入的字节流转为字符流
        try {
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream,charset);

            //2.快速的读取需要缓冲流
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);

            String s = null;
            StringBuilder builder = new StringBuilder();//字符串缓冲区

            while ((s = bufferedReader.readLine()) != null){
                //添加到字符串缓冲区
                builder.append(s);
            }

            bufferedReader.close();

            //返回字符串
            return builder.toString();


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


        return null;
    }