安卓NetworkManager实用类

Question

我试着做一个util类，但是不起作用，如果有人知道我错过了什么，请告诉我。

Obs: restOfUrl和siteUrl是站点的路径。

//我调用util类的对象：

NetworkManager networkManager = new NetworkManager(getApplicationContext());
networkManager.requestStringVolley("/restOfTheUrl");

// util类：

public class NetworkManager {

String prefUrl = "siteUrl";
RequestQueue mRequestQueue;
Context contextNet;
private static final String TAG = NetworkManager.class.getSimpleName();

public NetworkManager(Context context){
    contextNet = context;
}
public void requestStringVolley(String posUrl){
    mRequestQueue = Volley.newRequestQueue(contextNet);
    String url = prefUrl + posUrl;

    Response.Listener<String> listener = new Response.Listener<String>(){
        @Override
        public void onResponse(String response) {
            sucessResponse(response);
        }
    };

    Response.ErrorListener listenerError = new Response.ErrorListener(){
        @Override
        public void onErrorResponse(VolleyError error) {
            errorResponse(error);
        }
    };

    StringRequest stringRequest = new StringRequest(Request.Method.GET, url, listener, listenerError);

    mRequestQueue.add(stringRequest);
}

public void sucessResponse(String response){
    Log.v(TAG, "Sucess");
}

public void errorResponse(VolleyError errorResponse){
    Log.v(TAG, "Error");
}
}

// -错误：

04-13 19:18:45.096 23880-23880/com.dev.kamui.patrulhacomunitaria E/AndroidRuntime: FATAL EXCEPTION: main
                                                                               Process: com.dev.kamui.patrulhacomunitaria, PID: 23880
                                                                               java.lang.NullPointerException
                                                                                   at com.android.volley.Request.<init>(Request.java:136)
                                                                                   at com.android.volley.toolbox.StringRequest.<init>(StringRequest.java:43)
                                                                                   at com.dev.kamui.patrulhacomunitaria.NetworkManager$override.requestStringVolley(NetworkManager.java:41)
                                                                                   at com.dev.kamui.patrulhacomunitaria.NetworkManager$override.access$dispatch(NetworkManager.java)
                                                                                   at com.dev.kamui.patrulhacomunitaria.NetworkManager.requestStringVolley(NetworkManager.java:0)
                                                                                   at com.dev.kamui.patrulhacomunitaria.Pagina_Principal$1.onClick(Pagina_Principal.java:50)
                                                                                   at android.view.View.performClick(View.java:4438)
                                                                                   at android.view.View$PerformClick.run(View.java:18422)
                                                                                   at android.os.Handler.handleCallback(Handler.java:733)
                                                                                   at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                                   at android.os.Looper.loop(Looper.java:136)
                                                                                   at android.app.ActivityThread.main(ActivityThread.java:5001)
                                                                                   at java.lang.reflect.Method.invokeNative(Native Method)
                                                                                   at java.lang.reflect.Method.invoke(Method.java:515)
                                                                                   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
                                                                                   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
                                                                                   at dalvik.system.NativeStart.main(Native Method)

Answer 1

将其与以下各项配合使用：

sucessResponse(response.toString());

errorResponse(error);

public void sucessResponse(String response){
    Log.v(TAG, response);
}

public void errorResponse(VolleyError errorResponse){
    Log.v(TAG, "Error: " + errorResponse.getMessage());
}

我不知道为什么我要用这种方式工作...但我知道它是有效的，这正是我所需要的