【第一篇】Volley的使用之json请求

最近项目写完，有开始新的学习了，volley很久以前就接触了，也看了源码，然而却没有通过文章去记录自己的学习成果。

首先讲下volley的特点：

　　1，扩展性强。Volley 中大多是基于接口的设计，可配置性强。

　　 2，一定程度符合 Http 规范，包括返回 ResponseCode(2xx、3xx、4xx、5xx）的处理，请求头的处理，缓存机制的支持等。并支持重试及优先级定义。

　　3，默认 Android2.3 及以上基于 HttpURLConnection，2.3 以下基于 HttpClient 实现，这两者的区别及优劣在4.2.1 Volley中具体介绍。

　　4，提供简便的图片加载工具。

现在计划是：

1. 写volley相关demo
2. 分析volley源码
3. 扩展和完善volley,给volley添加一些更加方便开发的功能等。

在编写代码前首先导入volley的库或者引入jar包，这里不进行赘述，只讲使用。

demo1,json数据请求：

    首先请求的json数据格式：

1. {
      "weatherinfo" : {
         "Radar" : "JC_RADAR_AZ9200_JB",
         "SD" : "77%",
         "WD" : "东南风",
         "WS" : "2级",
         "WSE" : "2",
         "city" : "广州",
         "cityid" : "101280101",
         "isRadar" : "1",
         "njd" : "暂无实况",
         "qy" : "1004",
         "temp" : "24",
         "time" : "10:45"
      }
   }

首先创建javaBean:

1.  package com.soyoungboy.volleydemo.bean;
    import java.io.Serializable;
    import com.soyoungboy.volleydemo.utils.GsonImpl;
    public class WeathBean implements Serializable {
        /**
         *
         */
        private static final long serialVersionUID = 1L;
        public Weatherinfo weatherinfo;
        @Override
        public String toString() {
            return "WeathBean [weatherinfo=" + weatherinfo + "]";
        }
        public  static WeathBean getBeanFromJson(String response){
            WeathBean weathBean= GsonImpl.get().toObject(response, WeathBean.class);
            return weathBean ;
        }
        /**
         * Temporary class name, create by Json2Class.
         */
        public static class Weatherinfo implements Serializable {
            public String SD;
            public int isRadar;
            public String time;
            public int WSE;
            public String WS;
            public String WD;
            public String njd;
            public int qy;
            public String Radar;
            public int temp;
            public int cityid;
            public String city;
            public String getSD() {
                return SD;
            }
            public void setSD(String sD) {
                SD = sD;
            }
            public int getIsRadar() {
                return isRadar;
            }
            public void setIsRadar(int isRadar) {
                this.isRadar = isRadar;
            }
            public String getTime() {
                return time;
            }
            public void setTime(String time) {
                this.time = time;
            }
            public int getWSE() {
                return WSE;
            }
            public void setWSE(int wSE) {
                WSE = wSE;
            }
            public String getWS() {
                return WS;
            }
            public void setWS(String wS) {
                WS = wS;
            }
            public String getWD() {
                return WD;
            }
            public void setWD(String wD) {
                WD = wD;
            }
            public String getNjd() {
                return njd;
            }
            public void setNjd(String njd) {
                this.njd = njd;
            }
            public int getQy() {
                return qy;
            }
            public void setQy(int qy) {
                this.qy = qy;
            }
            public String getRadar() {
                return Radar;
            }
            public void setRadar(String radar) {
                Radar = radar;
            }
            public int getTemp() {
                return temp;
            }
            public void setTemp(int temp) {
                this.temp = temp;
            }
            public int getCityid() {
                return cityid;
            }
            public void setCityid(int cityid) {
                this.cityid = cityid;
            }
            public String getCity() {
                return city;
            }
            public void setCity(String city) {
                this.city = city;
            }
            @Override
            public String toString() {
                return "Weatherinfo [SD=" + SD + ", isRadar=" + isRadar + ", time="
                        + time + ", WSE=" + WSE + ", WS=" + WS + ", WD=" + WD
                        + ", njd=" + njd + ", qy=" + qy + ", Radar=" + Radar
                        + ", temp=" + temp + ", cityid=" + cityid + ", city="
                        + city + "]";
            }
        }
    }

   创建界面：

activity_json.xml

1. <?xml version="1.0" encoding="utf-8"?>
   <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:orientation="vertical" >
       <TextView
           android:id="@+id/lvWeatherTv"
           android:layout_width="match_parent"
           android:layout_height="match_parent" >
       </TextView>
   </LinearLayout>

   主要的逻辑：

1. 首先创建请求队列 mqueue;
2. 创建json请求jsonObjectRequest，实现请求成功和失败的逻辑编写；
3. 将请求放入请求队列中去。

 public class JsonActivity extends Activity {
     private static final String TAG = "com.soyoungboy.volleydemo.JsonActivity";
     private RequestQueue mQueue;
     private static final String WEATHER_LINK = "http://www.weather.com.cn/data/sk/101280101.html";
     private TextView lvWeatherTv;
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_json);
         lvWeatherTv = (TextView) findViewById(R.id.lvWeatherTv);
         mQueue = Volley.newRequestQueue(this);
         getWeatherInfo();
     }
     public void getWeatherInfo() {
         JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(
                 WEATHER_LINK, null, new Response.Listener<JSONObject>() {
                     @Override
                     public void onResponse(JSONObject response) {
                         if (!TextUtils.isEmpty(response.toString())) {
                             WeathBean weathBean = WeathBean
                                     .getBeanFromJson(response.toString());
                             lvWeatherTv.setText(weathBean.toString());
                         }
                     }
                 }, new Response.ErrorListener() {
                     @Override
                     public void onErrorResponse(VolleyError error) {
                         ToastUtils.toastL(getApplicationContext(),
                                 error.getMessage());
                     }
                 });
         mQueue.add(jsonObjectRequest);
     }
 }

显示结果：