Develop Reference

Volley second request return null

The first request done successfully but second request in queue return null , when setting break point and start debugging the second request get it's value successfully
class ListLoader extends AsyncTask<Void,Void,MerchantCategories[]>
{
MerchantCategories[] data;
protected void onPreExecute() {
progressBar.setVisibility(View.VISIBLE);
}
#Override
protected MerchantCategories[] doInBackground(Void... params) {
Gson g = new Gson();
gcm = GoogleCloudMessaging.getInstance(getApplicationContext());
try {
regid = gcm.register(PROJECT_NUMBER);
String msg="";
msg = "Device registered, registration ID=" + regid;
Log.i("GCM", msg);
EgxServices.getJsonFrom("http://inareg.com/APIs/RegisterAndroidDevice?registrationID="+regid,(Activity) c);
} catch (IOException e) {
e.printStackTrace();
}
MerchantCategories[] categs=g.fromJson(EgxServices.getJsonFrom("http://inareg.com/APIs/ListMerchantCategories",(Activity) c),MerchantCategories[].class);
return categs;
}
protected void onPostExecute(MerchantCategories[] response) {
if(response == null) {
progressBar.setVisibility(View.GONE);
}
else{
progressBar.setVisibility(View.GONE);
MerchantCategoriesAdp adp =new MerchantCategoriesAdp(c,R.layout.lst_merchant_categories,response);
drawerList.setAdapter(adp);
// Log.i("INFO", response);
// responseView.setText(response);
}
}
}
This method which i used to initialize a new request and return JSON String
public static String getJsonFrom(final String urlStr, Activity context) {
final Context c = context;
final SharedValue value = new SharedValue();
String result="";
StringRequest request = new StringRequest(Request.Method.GET,urlStr,new Response.Listener<String>(){
#Override
public void onResponse(String response) {
value.setResult(response);
}
},new Response.ErrorListener(){
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(c, "No Internet Connection",
Toast.LENGTH_LONG).show();
}
});
Volley.newRequestQueue(c).add(request);
return value.getResult();
}
as you can see that first request
EgxServices.getJsonFrom("http://inareg.com/APIs/RegisterAndroidDevice?registrationID="+regid,(Activity) c);
run successfully but the second one ,
EgxServices.getJsonFrom("http://inareg.com/APIs/ListMerchantCategories",(Activity) c);
always return null value ...
i need to know why ?????!!!

Try this :
request.setShouldCache(false);
before Volley.newRequestQueue(c).add(request);

i have lots of json Api how to create method/interface pass url get response

*how to create interface use any where android Json Volley Library please help me *
public void getJsonRequest(){//Create interface and jsonObjectRequest
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Request.Method.GET,url, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
list =parseJSONRequest(response);// create interface
adapter.setAllLinks(list); // create interface
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
errorJson.setVisibility(View.VISIBLE);
String map = VolleyErrorException.getErrror(error, getContext());
errorJson.setText(map);
}
});
requestQueue.add(jsonObjectRequest);
}

Here is solution. I have created a static method in a separate class nammed APIManager.
/**
* The method to create a Request with specific method except GET
*
* #param method The request Method ex. (Request.Method.POST)
* #param params The parameters map
* #param url The base url of webservice to be called
* #param requestTag The request Tag to assign when putting request to request queue
* #param listener The listener for request completion.
*/
public static void createPostRequest(int method, final Map<String, String> params, String url, String requestTag, final OnRequestCompletedListener listener) {
JsonObjectRequest request = new JsonObjectRequest(method, url, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
listener.onRequestCompleted(response);
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
listener.onRequestError(getErrorMessageFromVolleyError(error));
}
}) {
#Override
public String getBodyContentType() {
return "application/x-www-form-urlencoded";
}
#Override
public byte[] getBody() {
Uri.Builder builder = Uri.parse("http://example.com")
.buildUpon();
for (Map.Entry<String, String> entry : params.entrySet()) {
builder.appendQueryParameter(entry.getKey(),
entry.getValue());
}
return builder.build().getEncodedQuery().getBytes();
}
};
AppController.getInstance().addToRequestQueue(request, requestTag);
}
/**
* The interface for callback when API Request completes.
*/
public interface OnRequestCompletedListener {
/**
* The interface method called when API call successfully completes.
*
* #param jsonObject The JSONObject recieved from the API call.
*/
void onRequestCompleted(JSONObject jsonObject);
/**
* The interface method called when API call recieves any Error.
*
* #param errorMessage The error message
*/
void onRequestError(String errorMessage);
}
/**
* The method to convert volley error into user readable string message.
*
* #param error The volleyError recieved during API call
* #return The String containing the message related to error
*/
public static String getErrorMessageFromVolleyError(VolleyError error) {
if (error instanceof TimeoutError) {
return AppController.getContext().getString(R.string.time_out_error_message);
}
if (error instanceof NoConnectionError) {
return AppController.getContext().getString(R.string.no_connection_error_message);
}
if (error instanceof ServerError) {
return AppController.getContext().getString(R.string.server_error_message);
}
if (error instanceof NetworkError) {
return AppController.getContext().getString(R.string.network_error_message);
}
if (error instanceof ParseError) {
return AppController.getContext().getString(R.string.parse_error_message);
}
return null;
}
To call this method use it in any activity or fragment class like this way.
private void getEvaultFiles() {
Map<String, String> params = new HashMap<>();
params.put("EvaultId", item.id);
APIManager.createPostRequest(Request.Method.POST,params, AppConstants.GET_EVAULT_FILES_URL, "GETEVAULTFILES", new APIManager.OnRequestCompletedListener() {
#Override
public void onRequestCompleted(JSONObject jsonObject) {
Utils.hideProgressAndShowContent(EvaultDetailActivity.this);
listFiles.clear();
tvEmpty.setText("No Files to display");
try {
JSONArray files = jsonObject.getJSONObject("Result").getJSONArray("Files");
for (int i = 0; i < files.length(); i++) {
EvaultFile file = new EvaultFile();
JSONObject temp = files.getJSONObject(i);
file.name = temp.getString("FileName");
file.size = temp.getString("FileSize");
file.fileurl = temp.getString("FilePathFullImage");
listFiles.add(file);
}
adapter.notifyDataSetChanged();
} catch (JSONException e) {
e.printStackTrace();
}
}
#Override
public void onRequestError(String errorMessage, JSONObject data) {
}
});
}

android How to asynchronous request data and synchronous display data

I have two listview in my activity. I use asynhttpclient request data two times, but I don't know how to monitor the two times request to refresh my listview.
There are some codes.
loadData( Constant.newGameUrl ,"new");
loadData( Constant.hotGameUrl ,"hot");
/**
* request data
* #param url
* #param type
*/
public void loadData( String url,
final String type,final int initpage){
H5RestClient.request(url, null, new OnRequestListener(){
#SuppressLint("ShowToast")
#Override
public void onRequestFinish(boolean ret, String data) {
// TODO Auto-generated method stub
List<Game> games = new ArrayList<Game>();
if( ret == true ){
try {
games = JsonParseUtil.parseGame(data);
} catch (JSONException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
if( games != null ){
netStateView.show(NetState.CONTENT);
if( type.equals("new")){
listNew.addAll(games);
newAdapter.notifyDataSetChanged();//this listview
}else if( type.equals("hot") ){
listHot.addAll(games);
hotAdapter.notifyDataSetChanged();//I want to display the two list view
}
}
else{
Toast.makeText(context, "result is null", Toast.LENGTH_SHORT).show();
}
}else{
Toast.makeText(context, "request is failed", Toast.LENGTH_SHORT).show();
}
}
});
}
public static void request(final String url, final RequestParams params, final OnRequestListener listener) {
AsyncHttpResponseHandler handler = new AsyncHttpResponseHandler(){
#Override
public void onSuccess(int statusCode, String responseBody){
Log.i(TAG, "success "+responseBody);
listener.onRequestFinish(true, responseBody);
}
#Override
public void onFailure(Throwable e, String responseBody){
Log.e(TAG, "fail "+responseBody);
listener.onRequestFinish(false, responseBody + "");
}
};
client.get(url, handler);
}
How to display the two listview at the same time?
newAdapter.notifyDataSetChanged();//this listview
hotAdapter.notifyDataSetChanged();//I want to display the two list view

I recommend you to use Google Volley librairy for HTTP request.
See the doc here : http://developer.android.com/training/volley/index.html
Some code for your problem :
StringRequest strRequest1 = new StringRequest(url, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
// CODE REQUEST 1
}
}, 0, 0, null, null);
StringRequest strRequest2 = new StringRequest(url, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
// CODE REQUEST 2
}
}, 0, 0, null, null);
RequestQueue rq = Volley.newRequestQueue(this);
rq.add(strRequest1);
rq.add(strRequest2);

Two booleans, one per transaction. Once a transaction is complete, it checks the two boolean. If the two are true, you display your data, if not it only sets its boolean to true...

Android volley last request post call on network drop?

Volley works well when there is network but it goes weird when network drops.
When network is doping ie network strength is going down and i make a post request then nothing happens but once the network regain to full strength it makes the call to the previous post request not the new one?
when i clear the cache it works well...
how to solve this issue, why i am getting previous post response?
// Implements required listeners
public class VolleyServices<T> implements Response.Listener<T>, ErrorListener{
private int id; // request id
private RequestQueue request; // volley request queue
private VolleyResponce<T> listener; // callback listener
private Class<T> clazz; // parsing class
public interface VolleyResponce<T> {
public void OnSuccess(T response,int id);
public void OnError(ServerError error,int id);
}
// Constructor
public VolleyServices(VolleyResponce<T> listener,Context context) {
this.listener = listener;
request = VolleyRequest.getInstance(context).getRequestQueue();
}
// call to post the request with parse class, post parameters in map and request id
public void post(String methodName, HashMap<String, String> map,Class<T> clazz,int id) {
String url = baseUrl + methodName;
this.clazz = clazz;
this.id = id;
GsonRequest<T> myReq = new GsonRequest<T>(Request.Method.POST,url,clazz,map,this,this);
myReq.setTag(id);
request.add(myReq);
}
#Override
public void onResponse(T response) {
if(response != null && clazz == response.getClass()){
listener.OnSuccess(response,this.id);
}
}
#Override
public void onErrorResponse(VolleyError volleyError) {
ServerError error = null;
if(volleyError instanceof NetworkError) {
error = new ServerError("No internet Access, Check your internet connection.","400");
}
if(volleyError instanceof AuthFailureError) {
error = new ServerError("Authentication Failure","400");
}
if(volleyError instanceof ParseError) {
error = new ServerError("Parsing error","400");
}
if(volleyError instanceof NoConnectionError) {
error = new ServerError("No internet Access, Check your internet connection.","400");
}
if(volleyError instanceof TimeoutError) {
error = new ServerError("Request timed out, Please try again later.","400");
}
if(volleyError.networkResponse != null && volleyError.networkResponse.statusCode == 500) {
error = new ServerError("Internal server error","400");
}
else {
try {
if(volleyError.networkResponse != null) {
String responseBody = new String(volleyError.networkResponse.data, "utf-8" );
try{
Gson gson = new Gson();
error = gson.fromJson(responseBody, ServerError.class);
if(error.status == null) {
error.status = "";
}
}catch(Exception e){
e.printStackTrace();
}
} else {
error = new ServerError("Unknown Error","400");
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
listener.OnError(error,this.id);
}
Some log message i captured which explains everything in detail
log link

Android - How to get calling Activity?

An Activity (SignInActivity) is calling a method in FunkcjeAPI which execute an AsyncTask.
My AsyncTask should show a ProgressDialog using an calling Activity. I don't know how to give it an correct Activity to the constructor. I tried a lot of thing, read a lot of tutorials and questions on SO, but I can't find solution. FunkcjeAPI isn't an Activity so I can't write new Logowanie(this).execute(argumenty);
AsyncTask calling code :
public class FunkcjeAPI {
static String dozwrotu = null;
public static String zalogujSie(final String nick, final String haslo)
{
String[] argumenty = {nick, haslo};
new Logowanie(/* WHAT HERE ? */).execute(argumenty); // HELP ME IN THAT LINE !!!!!!!!!!!!!
return dozwrotu;
}
My AsyncTask class code (it is in FunkcjeAPI class):
private class Logowanie extends AsyncTask<String, Void, String>
{
Activity wywolujaceActivity;
public Logowanie(Activity wywolujaceActivity) {
this.wywolujaceActivity = wywolujaceActivity;
}
#SuppressWarnings("deprecation")
#Override
protected void onPreExecute() {
wywolujaceActivity.showDialog(SignInActivit.PLEASE_WAIT_DIALOG);
}
#Override
protected String doInBackground(final String... argi) {
final JSONParser jParser = new JSONParser();
new Thread(new Runnable() {
public void run() {
final String json = jParser.getJSONFromUrl("http://tymonradzik.pl/THUNDER_HUNTER/thapi.php?q=login&username=" + argi[0] + "&password=" + argi[1] + "&imei=");
Handler mainHandler = new Handler(Looper.getMainLooper());
mainHandler.post(new Runnable() {
#Override
public void run() {
JSONObject jObject;
try {
jObject = new JSONObject(json);
Log.wtf("Link", "http://tymonradzik.pl/THUNDER_HUNTER/thapi.php?q=login&username=" + argi[0] + "&password=" + argi[1] + "&imei=");
Log.wtf("Link", json);
String error = jObject.getString("error");
if(error == "You reached daily query limit !") { nadajWartosc("You reached daily query limit !"); }
if(error == "0") {nadajWartosc(jObject.getString("token"));}
if(error == "1") {nadajWartosc("1");}
if(error == "Invalid username") {nadajWartosc("Invalid username");}
if(error == "Invalid password") {nadajWartosc("Invalid password");}
if(error == "This user is already logged in !") {nadajWartosc("This user is already logged in !");}
} catch (JSONException e1) {
e1.printStackTrace();
}
catch (NullPointerException e)
{
e.printStackTrace();
}
}
});
}}).start();
return dozwrotu;
}
#Override
protected void onPostExecute(String result) {
wywolujaceActivity.removeDialog(SignInActivit.PLEASE_WAIT_DIALOG);
}
}

Add one more parameter to zalogujSie() method that takes an Activity, and then use this parameter to start the AsyncTask:
public static String zalogujSie(Activity activity, final String nick, final String haslo)
{
// .....
new Logowanie(activity).execute(argumenty);
return dozwrotu;
}
Then you would call this method from the activity like this:
FunkcjeAPI.zalogujSie(this, "Nick", "Haslo");