Volley DeliverResponse 未被调用

Question

我正在使用 Volley，我看到 parseNetworkResponse\n 被调用，一切正常。解析很好，我可以在日志中看到\n并且我不\xe2\x80\x99t 返回 null。\n但是由于某种原因，deliverResponse 没有被调用？\n如何解释为什么会发生这种情况或者我如何调试它？

\n\n

甚至这个：

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@Override\n        protected Response<Object> parseNetworkResponse(NetworkResponse response) {\n            Log.i(\xe2\x80\x9cTEST\xe2\x80\x9d, "Returning nothing from dummy parseNetworkResponse....");\n            Response<Object> jsonResponse = Response.success(new Object(), HttpHeaderParser.parseCacheHeaders(response));\n            Log.i("TEST", "Returning nothing....");\n            return jsonResponse;\n        } \n

\n\n

尽管我可以在 LOGCAT 中看到日志，但最终并没有调用 DeliverResponse

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更新：
\n我通过了调试器，最终在 NetworkDispatcher 中的代码中（在网络解析完成和后响应之后）\nrequest.markDelivered();\nmDelivery.postResponse(request, response);\n然后是代码在 ExecutorDelivery.postResponse 中执行：

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mResponsePoster.execute(new ResponseDeliveryRunnable(request, response, runnable));\n

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这最终会调用 mRequest.deliverResponse(mResponse.result);\n但是当我在 ResponseDeliveryRunnable.run 中添加断点时，代码不会中断，因此我假设调用 DeliverResponse 的可运行程序没有运行。
\n知道为什么会发生这种情况吗？

\n

Answer 1

您还应该查找错误Network Response并通知 Volley，而不是使用对象，您还需要重写parseNetworkError, deliverResponse方法。请参阅我的示例（请不要被这么多样板代码淹没）

public interface JsonParser_<T> {
        public T parseResponse_(JSONObject json);

        public T parseResponse_(JSONArray json);
    }



/**
     * 
     * @param tag
     *            : to tag your request with some string, so that you can cancel
     *            them any time
     * @param method
     *            <pre>
     * int DEPRECATED_GET_OR_POST = -1;
     * int GET = 0;
     * int POST = 1;
     * int PUT = 2;
     * int DELETE = 3;
     * int HEAD = 4;
     * int OPTIONS = 5;
     * int TRACE = 6;
     * int PATCH = 7;
     * </pre>
     * @param url
     *            URL to hit
     * @param postParams
     *            Parameters that embeds with the URL itself
     * @param headerParams
     *            Parameters that goes inside header
     * @param jsonDelivery
     *            Listener will be called with JSON so that you can parse your
     *            JSON off the UI thread
     * @param resultDelivery
     *            It will return the resulf of delivery, very important to
     *            return the result in the first listener in parsing JSON
     * @param errorListener
     *            It anything goes wrong
     */
    @SuppressWarnings("hiding")
    protected final <T> void fetchAndParseResponse(final String tag,
            final int method, final String url,
            final Map<String, String> postParams,
            final Map<String, String> headerParams,
            final JsonParser_<T> jsonDelivery,
            final Response.Listener<T> resultDelivery,
            final Response.ErrorListener errorListener) {

        AppContext.requestQueue.start();

        AppContext.requestQueue.add(new Request<T>(method, url,
                new Response.ErrorListener() {

                    @Override
                    public void onErrorResponse(VolleyError error) {
                        setException(error);
                        if (errorListener != null)
                            // errorListener.onErrorResponse(wrapError(error));
                            errorListener.onErrorResponse(error);
                    }
                }) {

            @Override
            protected Response<T> parseNetworkResponse(NetworkResponse response) {

                T pojo = null;

                statusCode = response.statusCode;

                try {

                    String jsonString = new String(response.data, "UTF-8");
                    char char_ = new JSONTokener(jsonString).next();

                    if (char_ == '{') {

                        JSONObject json = new JSONObject(jsonString);

                        // isResponseOk(json);

                        pojo = jsonDelivery.parseResponse_(json);

                    } else {

                        JSONArray json = new JSONArray(jsonString);
                        pojo = jsonDelivery.parseResponse_(json);

                    }

                } catch (UnsupportedEncodingException e) {

                    setException(e);
                    // return Response.error(wrapError(new VolleyError(e)));
                    return Response.error((new VolleyError(e)));

                } catch (JSONException e) {

                    setException(e);
                    // return Response.error(wrapError(new VolleyError(e)));
                    return Response.error((new VolleyError(e)));
                }

                return Response.success(pojo,
                        HttpHeaderParser.parseCacheHeaders(response, true));

            }

            @Override
            protected VolleyError parseNetworkError(VolleyError volleyError) {
                if (volleyError.networkResponse != null
                        && volleyError.networkResponse.data != null) {
                    VolleyError error = new VolleyError(new String(
                            volleyError.networkResponse.data));
                    volleyError = error;
                }

                return volleyError;
            }

            @Override
            protected void deliverResponse(T response) {
                if (resultDelivery != null)
                    resultDelivery.onResponse(response);
                else
                    VolleyLog.wtf("No listener attached with %s class", this
                            .getClass().getName());
            }

            @Override
            public Map<String, String> getHeaders() throws AuthFailureError {
                if (headerParams == null) {
                    Map<String, String> map = new HashMap<String, String>(1);
                    if (AppContext.userPojo != null) {
                        map.put("sid", AppContext.userPojo.SID);
                    }
                    return map;
                } else {
                    if (AppContext.userPojo != null) {
                        headerParams.put("sid", AppContext.userPojo.SID);
                    }
                }

                return headerParams;
            }

            @Override
            protected Map<String, String> getParams() throws AuthFailureError {
                if (postParams == null)
                    return super.getParams();
                else
                    return postParams;
            }
        }.setRetryPolicy(new DefaultRetryPolicy()).setTag(tag));

    }

用法：

fetchAndParseResponse(tag, Method.POST, AZ_API.SOME_URL, null, null, new JsonParser_<StatusMessage>() {

            @Override
            public StatusMessage parseResponse_(JSONObject json) {

                requestStatus = parseStatus(json);
                message = parseMessage(json);

                StatusMessage msg = new StatusMessage();
                msg.setMessage(message);
                msg.setStatus(requestStatus);

                return msg;

            }

            @Override
            public StatusMessage parseResponse_(JSONArray json) {

                return null;
            }

        }, listener, new Response.ErrorListener() {

            @Override
            public void onErrorResponse(VolleyError error) {                
                errorListener.onErrorResponse(error);
            }
        });