Question

我在Android中遇到Volley请求的问题，我正在尝试从服务器中获取学生的蝙蝠侠，然后获取与每个batchno详细信息相对应的学生详细信息。我的日志显示来自服务器的响应，但它们都是随机顺序。此外，响应在recyclerview中以随机顺序设置。这是批量和学生的排球和json：

    private void setData() {
        students = new ArrayList<>();   
        StringRequest batchRequest=new StringRequest(Request.Method.POST, BATCH_URL, new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {
                try {
                    parseBatchJsonResponse(response);
                } catch (JSONException e) {
                    e.printStackTrace();
                }

            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                Log.d("ResponseError",""+error.toString());

            }
        });
              VolleySingleton.getInstance(getApplicationContext()).addToRequestQueue(studentRequest,"req");



    }

    private void parseBatchJsonResponse(String response) throws JSONException {
        Log.d("Resp",""+response);
        JSONObject batchObject=new JSONObject(response);
        JSONArray batchArray=batchObject.getJSONArray("result");
        for (int i=0;i<batchArray.length();i++){
            JSONObject bObject=batchArray.getJSONObject(i);
            batchNos=bObject.getString("batch");
            Log.d("batchNo",""+batchNos);
            getStudentData(batchNos);



        }

    }

    private void getStudentData(String batchNo) {
       batchNos =batchNo= "\"" + batchNo + "\"";

        String studentURl=STUDENT_URL+batchNo.trim();
        Log.d("SURL",""+studentURl);

        StringRequest studentRequest =new StringRequest(Request.Method.GET,studentURl, new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {

                try {
                    Log.d("Student",""+response+batchNos);
                   parseStudentJson(response);


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


            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {

            }
        });
               VolleySingleton.getInstance(getApplicationContext()).addToRequestQueue(studentRequest,"req");

    }

    private void parseStudentJson(String batchNo) throws JSONException {
//        students.clear();
        JSONObject studentOb=new JSONObject(batchNo);
        JSONArray stuArray=studentOb.getJSONArray("result");
        for (int i=0;i<stuArray.length();i++){
            JSONObject stu=stuArray.getJSONObject(i);
            String stuName=stu.getString("student");
            students.add(new Student(stuName,100));
            Log.d("BNO",""+batchNos);

        }
        batches.add(new Batch(batchNos,students));
        adapter.notifyDataSetChanged();

Answer 1

不要每次都有新请求队列。请单个请求队列。

public class VolleySingleton {
private static VolleySingleton mAppSingletonInstance;
private RequestQueue mRequestQueue;
private ImageLoader mImageLoader;
private static Context mContext;
private Request.Priority Low;

private VolleySingleton(Context context) {
    mContext = context;
    mRequestQueue = getRequestQueue();

    mImageLoader = new ImageLoader(mRequestQueue,new ImageLoader.ImageCache()
    {
        private final LruCache<String, Bitmap>
                cache = new LruCache<String, Bitmap>(20);

        @Override
        public Bitmap getBitmap(String url) {
            return cache.get(url);
        }

        @Override
        public void putBitmap(String url, Bitmap bitmap) {
            cache.put(url, bitmap);
        }
    });
}



public static synchronized VolleySingleton getInstance(Context context) {
    if (mAppSingletonInstance == null) {
        mAppSingletonInstance = new VolleySingleton(context);
    }
    return mAppSingletonInstance;
}



public RequestQueue getRequestQueue() {
    if (mRequestQueue == null) {

        mRequestQueue = Volley.newRequestQueue(mContext.getApplicationContext());
    }
    return mRequestQueue;
}



public <T> void addToRequestQueue(Request<T> req, String tag) {
    req.setTag(tag);
    getRequestQueue().add(req);
}



public ImageLoader getImageLoader() {
    return mImageLoader;
}



public void cancelPendingRequests(Object tag) {
    if (mRequestQueue != null) {
        mRequestQueue.cancelAll(tag);
    }
}


}

然后

VolleySingleton.getInstance(context).addToRequestQueue(jsonObjectRequest,tag);

Volley多次请求android

1 个答案: