Volley简单封装之Gson解析
这里设计了一个InternetHelper接口，然后实现了接口 VolleyHelper类，Activity调用 VolleyHelper类中的方法发起网络请求，然后通过继承抽象类VolleyCallBack来获得网络请求的结果，通知View视图层更新UI。至此，就将View视图和网络请求（数据处理）隔离开。
思路：
{“weathering”{“city”:”beijing”,”cityid”:”101190404”,”temp1”:”12C”,”temp2”:”16C”,
“weather”:”sunny”,”img1”:”n0.gif”,”img2”:”d1.gif”,”ptime”:”18:00”}}
例如需要解析上的Json数据。通过Volley请求网络数据，这里为了简单，只封装了GET请求（即从服务器获取一段Json字符串）。这里为了网络请求和Gson解析的代码能够复用，使用了泛型来定义VolleyCallBack抽象类，在继承该抽象类的时候传入了实际类型（JavaBean类型），对于不同形式的Json数据，我们只需要编写不同的JavaBean类，在继承时传入对应的类型即可，不需要去修改网络请求的代码。
InternetHelper接口：
public interface InternetHelper
{
void getData(String url , VolleyCallBack callBack);
}VolleyHelper实现类：
public class VolleyHelper implements InternetHelper
{
private Gson gson;
private RequestQueue requestQueue;
public VolleyHelper(Context context)
{
gson = new Gson();
requestQueue = Volley.newRequestQueue(context);
}
@Override
public void getData(String url, final VolleyCallBack callBack)
{
StringRequest stringRequest = new StringRequest("http://192.168.1.100/" + url + ".json",
new Response.Listener()
{
@Override
public void onResponse(String response)
{
if (response != null && !response.equals(""))
{
if (callBack.mType == String.class)
{
callBack.onSuccess(response , response);
}
else
{
try
{
Object object = gson.fromJson(response, callBack.mType);
callBack.onSuccess(response , object);
}
catch (JsonParseException e)
{
callBack.onError(response , e);
}
}
}
else
{
callBack.onError(response , null);
}
}
}, new Response.ErrorListener()
{
@Override
public void onErrorResponse(VolleyError volleyError)
{
callBack.onFailure(volleyError);
}
});
requestQueue.add(stringRequest);
}
} VolleyCallBack回调抽象类：
public abstract class VolleyCallBack
{
protected Type mType;
static Type getSuperclassTypeParameter(Class subClass)
{
Type superclass = subClass.getGenericSuperclass();
if (superclass instanceof Class)
{
throw new RuntimeException("Missing type parameter.");
}
ParameterizedType parameterized = (ParameterizedType) superclass;
return $Gson$Types.canonicalize(parameterized.getActualTypeArguments()[0]);
}
public VolleyCallBack()
{
mType = getSuperclassTypeParameter(getClass());
}
public abstract void onFailure(VolleyError error);
public abstract void onSuccess(String response ,T t);
public abstract void onError(String response , Exception e);
} 实体类Weather：
public class Weather
{
public Weatherinfo weatherinfo;
public Weatherinfo getWeatherinfo()
{
return weatherinfo;
}
public void setWeatherinfo(Weatherinfo weatherinfo)
{
this.weatherinfo = weatherinfo;
}
public static class Weatherinfo
{
public String city;
public String cityid;
public String temp1;
public String temp2;
public String weather;
public String img1;
public String img2;
public String ptime;
public String getCityid() {
return cityid;
}
public void setCityid(String cityid) {
this.cityid = cityid;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getTemp1() {
return temp1;
}
public void setTemp1(String temp1) {
this.temp1 = temp1;
}
public String getTemp2() {
return temp2;
}
public void setTemp2(String temp2) {
this.temp2 = temp2;
}
public String getWeather() {
return weather;
}
public void setWeather(String weather) {
this.weather = weather;
}
public String getImg1() {
return img1;
}
public void setImg1(String img1) {
this.img1 = img1;
}
public String getImg2() {
return img2;
}
public void setImg2(String img2) {
this.img2 = img2;
}
public String getPtime() {
return ptime;
}
public void setPtime(String ptime) {
this.ptime = ptime;
}
}
}MainActivity类：
public class MainActivity extends Activity
{
private InternetHelper weatherModel;
private EditText input;
private Button button;
private TextView show;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
weatherModel = new VolleyHelper(this);
init();
}
private void init()
{
input = (EditText) findViewById(R.id.input);
button = (Button) findViewById(R.id.button);
show = (TextView) findViewById(R.id.show);
button.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View view)
{
weatherModel.getData(input.getText().toString().trim() , new VolleyCallBack()
{
@Override
public void onFailure(VolleyError error)
{
error.printStackTrace();
}
@Override
public void onSuccess(String response, Weather weatherInfo)
{
showData(weatherInfo);
}
@Override
public void onError(String response, Exception e)
{
Log.d("Error" , response);
e.printStackTrace();
}
});
}
});
}
private void showData(Weather weatherInfo)
{
Weather.Weatherinfo weatherMsg = weatherInfo.getWeatherinfo();
StringBuilder result = new StringBuilder();
result.append("city: " + weatherMsg.getCity() + "\n"
+ "city no: " + weatherMsg.getCityid() + "\n"
+ "temp1: " + weatherMsg.getTemp1() + "\n"
+ "temp2: " + weatherMsg.getTemp2() + "\n"
+ "weather: " + weatherMsg.getWeather() + "\n"
+ "img1: " + weatherMsg.getImg1() + "\n"
+ "img2: " + weatherMsg.getImg2() + "\n"
+ "ptime:" + weatherMsg.getPtime());
show.setText(result.toString() , TextView.BufferType.NORMAL);
}
} 主布局：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<EditText
android:id="@+id/input"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="3"
android:hint="Input CityId"/>
<Button
android:id="@+id/button"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:textSize="20sp"
android:text="下载"/>
LinearLayout>
<TextView
android:id="@+id/show"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="20sp"
android:text=""/>
LinearLayout>至此对Volley的简单封装完毕，如有不妥之处，欢迎大家批评指责谢谢！