我想构建一个Utils类，以使Volley调用更简单，如下所示：
Utils.java：
public class Utils { static JsonObjectRequest mJsonObjectRequest; protected static boolean busy = true; public static JSONObject makeJsonObjectRequest(Context context, int method, String url){ final JSONObject[] jsonObject = new JSONObject[1]; mJsonObjectRequest = new JsonObjectRequest (method, url, null, new Response.Listener<JSONObject>() { @Override public void onResponse(JSONObject response) { jsonObject[0] = response; busy = false; } }, new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { // TODO Auto-generated method stub try { jsonObject[0] = new JSONObject(error.toString()); } catch (JSONException e) { e.printStackTrace(); } busy = false; } }); // Access the RequestQueue through your singleton class. VolleySingleton.getInstance(context).addToRequestQueue(mJsonObjectRequest); while (true) { if (!busy) break; } return jsonObject[0]; } }
MainActivity.java：
JSONObject jsonObject = Utils.makeJsonObjectRequest(this, Request.Method.GET, url); mTxtDisplay.setText("Response: " + jsonObject.toString());
当应用运行时，jsonObject始终为null。我想问一下是否可以延迟在makeJsonObjectRequest中返回jsonObject [0]直到调用onResponse。我可以这样做吗？。
我创建了此文件，并按照以下方式进行管理，请看一下，希望对您有用
public class APIManager { public static void createRequest(Context c, String requestTag, String endPoint, List<NameValuePair> params, final OnRequestCompletedListener listener, TransParentProgressDialog pd) { ServerDetails serverDetails = new ServerDetails(c, endPoint, params); JsonObjectRequest request = new JsonObjectRequest(Method.GET, serverDetails.getQueryUrl(), null, new Response.Listener<JSONObject>() { @Override public void onResponse(JSONObject response) { listener.onRequestCompleted(response); } }, getErrorListener(c, pd)) { }; AppController.getInstance().addToRequestQueue(request, requestTag); } public static ErrorListener getErrorListener(final Context c, final TransParentProgressDialog pd, final TextView tvEmpty, final String errorText) { Response.ErrorListener listener = new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { if (pd != null && pd.isShowing()) { pd.dismiss(); } if (tvEmpty != null) { tvEmpty.setText(errorText); } MyDialog dialog; Log.d("volley-error", error.toString()); if (error instanceof TimeoutError) { dialog = new MyDialog(c, "Server Timeout"); dialog.show(); return; } else if (error instanceof NoConnectionError) { dialog = new MyDialog(c, "No Connection or Invalid Url"); dialog.show(); return; } else if (error instanceof ServerError) { NetworkResponse response = error.networkResponse; if (response != null) { // int statusCode = response.statusCode; byte[] data = response.data; if (data != null) { String str = new String(data); try { JSONObject object = new JSONObject(str); Log.d("error response", object.toString()); if (object.has("errors")) { JSONArray errors = object .getJSONArray("errors"); JSONObject errorObject = errors .getJSONObject(0); dialog = new MyDialog(c, "Error!", errorObject.getString("message")); dialog.show(); } else { dialog = new MyDialog(c, "Error!", object.toString()); dialog.show(); } } catch (JSONException e) { e.printStackTrace(); dialog = new MyDialog(c, "Error!", "Error"); dialog.show(); } } else { dialog = new MyDialog(c, "Server Error"); dialog.show(); } } else { dialog = new MyDialog(c, "Server Error"); dialog.show(); } } else if (error instanceof NetworkError) { NetworkResponse response = error.networkResponse; if (response != null) { // int statusCode = response.statusCode; byte[] data = response.data; if (data != null) { String str = new String(data); try { JSONObject object = new JSONObject(str); Log.d("error response", object.toString()); if (object.has("errors")) { JSONArray errors = object .getJSONArray("errors"); JSONObject errorObject = errors .getJSONObject(0); dialog = new MyDialog(c, "Error!", errorObject.getString("message")); dialog.show(); } else { dialog = new MyDialog(c, "Error!", object.toString()); dialog.show(); } } catch (JSONException e) { e.printStackTrace(); dialog = new MyDialog(c, "Error!", "Error"); dialog.show(); } } else { dialog = new MyDialog(c, "Network Error"); dialog.show(); } } else { dialog = new MyDialog(c, "Network Error"); dialog.show(); } } else if (error instanceof ParseError) { dialog = new MyDialog(c, "Parse Error"); dialog.show(); } else if (error instanceof AuthFailureError) { NetworkResponse response = error.networkResponse; if (response != null) { // int statusCode = response.statusCode; byte[] data = response.data; if (data != null) { String str = new String(data); try { JSONObject object = new JSONObject(str); Log.d("error response", object.toString()); if (object.has("errors")) { JSONArray errors = object .getJSONArray("errors"); JSONObject errorObject = errors .getJSONObject(0); dialog = new MyDialog(c, "Error!", errorObject.getString("message")); dialog.show(); } else { dialog = new MyDialog(c, "Error!", object.toString()); dialog.show(); } } catch (JSONException e) { e.printStackTrace(); dialog = new MyDialog(c, "Error!", "Error"); dialog.show(); } } else { dialog = new MyDialog(c, "Error!", "Error"); dialog.show(); } } else { dialog = new MyDialog(c, "Error connecting server"); dialog.show(); } } } }; return listener; } }
并按要求完成回叫的界面是
public interface OnRequestCompletedListener { public void onRequestCompleted(JSONObject response); }
