I want to receive sever data ONLY when connected to the internet. Everything works fine (fetching data, displaying data) also caching the data received is fine.
The Only issue I get is when the internet is on.
The data I get/displayed is from both the server and the cached one and I can't seem to find a way to display ONLY sever data when internet is on and cache when internet is OFF.
private void NotesView() {
StringRequest stringRequest=new StringRequest(Request.Method.POST, SERVER_URL, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONArray jsonArray=new JSONArray(response);
for (int i=0;i<jsonArray.length();i++){
//looping through the array
mAdapter.notifyDataSetChanged();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
//errors
}
}){
//offline availability cache for 24 hours
#Override
protected Response<String> parseNetworkResponse(NetworkResponse response) {
try {
Cache.Entry cacheEntry = HttpHeaderParser.parseCacheHeaders(response);
if (cacheEntry == null) {
cacheEntry = new Cache.Entry();
}
final long cacheHitButRefreshed = 3 * 60 * 1000; // in 3 minutes cache will be hit, but also refreshed on background
final long cacheExpired = 24 * 60 * 60 * 1000; // in 24 hours this cache entry expires completely
long now = System.currentTimeMillis();
final long softExpire = now + cacheHitButRefreshed;
final long ttl = now + cacheExpired;
cacheEntry.data = response.data;
cacheEntry.softTtl = softExpire;
cacheEntry.ttl = ttl;
String headerValue;
headerValue = response.headers.get("Date");
if (headerValue != null) {
cacheEntry.serverDate = HttpHeaderParser.parseDateAsEpoch(headerValue);
}
headerValue = response.headers.get("Last-Modified");
if (headerValue != null) {
cacheEntry.lastModified = HttpHeaderParser.parseDateAsEpoch(headerValue);
}
cacheEntry.responseHeaders = response.headers;
final String string = new String(response.data,
HttpHeaderParser.parseCharset(response.headers));
return Response.success(string, cacheEntry);
} catch (UnsupportedEncodingException e) {
return Response.error(new ParseError(e));
}
}
#Override
protected void deliverResponse(String response) {
super.deliverResponse(response);
}
#Override
protected VolleyError parseNetworkError(VolleyError volleyError) {
return super.parseNetworkError(volleyError);
}
#Override
public void deliverError(VolleyError error) {
super.deliverError(error);
}
//get current user id
#Override
protected Map<String, String> getParams() throws AuthFailureError {
User user=PreferenceManager.getInstance(getApplicationContext()).getUser();
int id=user.getId();
Map<String, String> params = new HashMap<String, String>();
params.put("id", String.valueOf(id));
return params;
}
};
MySingleton.getInstance(getApplicationContext()).addToRequestQueue(stringRequest);
}
When connected to the Internet I want to get server response only and not the cached data.
if(connected()) { stringRequest.setShouldCache(false);} just mAke your connected method which returns true if connected to internet..
Related
I want to send a DELETE request to an API to delete a city with the given id. In the API request documentation it says that the DELETE request requires as parameters the authentication token and the city id. When I run the code below I always get a com.android.volley.AuthFailureError.
Here's my code:
void deleteCity(String cityId, final VolleyResponseListener volleyResponseListener){
String url = baseUrl + "city";
try {
JSONObject params = new JSONObject();
params.put("token", token);
params.put("city_id", cityId);
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest
(Request.Method.DELETE, url, params, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try{
String success = response.get("success").toString();
if(success.equals("true")){
volleyResponseListener.onResponse();
}else{
String errorMessage = response.get("errorMessage").toString();
throw new Exception(errorMessage);
}
} catch (Exception e) {
volleyResponseListener.onError(e.getMessage());
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
System.out.println(error);
volleyResponseListener.onError("Volley Error");
}
});
requestQueue.add(jsonObjectRequest);
}catch (JSONException e){
volleyResponseListener.onError("Param error");
}
}
UPDATE:
I solved the problem by adding the city id as a query in the HTTP request and sent the authentication token in the header. Here is the final code:
void deleteCity(String cityId, final VolleyResponseListener volleyResponseListener){
String url = baseUrl + "city?city_id="+cityId;
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest
(Request.Method.DELETE, url, null, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try{
String success = response.get("success").toString();
if(success.equals("true")){
volleyResponseListener.onResponse();
}else{
String errorMessage = response.get("errorMessage").toString();
throw new Exception(errorMessage);
}
} catch (Exception e) {
volleyResponseListener.onError(e.getMessage());
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
System.out.println(error);
volleyResponseListener.onError("Volley Error");
}
}){
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String, String> headers = super.getHeaders();
if (headers == null || headers.equals(Collections.emptyMap())) {
headers = new HashMap<String, String>();
}
headers.put("token", token);
return headers;
}
};
requestQueue.add(jsonObjectRequest);
}
I sent request with postman its working, but volley doesn't work. I always get error! I searched stackoverflow volley returns error when response is empty but i added CustomJsonObjectRequest still the issue remains.
Error message
Volley org.json.JSONException: End of input at character 0 of
CustomJsonObjectRequest
public class CustomJsonObjectRequest extends JsonObjectRequest {
public CustomJsonObjectRequest(int method, String url, JSONObject jsonRequest, Response.Listener<JSONObject> listener, Response.ErrorListener errorListener) {
super(method, url, jsonRequest, listener, errorListener);
}
#Override
protected Response<JSONObject> parseNetworkResponse(NetworkResponse response) {
try {
if (response.data.length == 0) {
byte[] responseData = "{}".getBytes("UTF8");
response = new NetworkResponse(response.statusCode, responseData, response.headers, response.notModified);
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return super.parseNetworkResponse(response);
}
}
Volley request
EcoElement ecoElement = ecoElementArrayList.get(position);
Map<String, String> params = new HashMap<String, String>();
params.put("Id", ecoElement.getId().toString());
params.put("Checked", ecoElement.getChecked().toString());
JSONObject ObjParams = new JSONObject(params);
try {
CustomJsonObjectRequest getRequest = new CustomJsonObjectRequest(Request.Method.PUT, "https://ourwebsite.sslbeta.de/api/gardenapi/updateecoelements", ObjParams,
response -> {
Toast.makeText(getContext(), ""+response, Toast.LENGTH_SHORT).show();
progressBar.setVisibility(View.GONE);
},
error -> {
Toast.makeText(getContext(), ""+error.toString(), Toast.LENGTH_SHORT).show();
progressBar.setVisibility(View.GONE);
}
);
RequestQueueSingleton.getInstance(getContext()).addToRequestQueue(getRequest);
} catch (Exception e) {
Toast.makeText(getContext(), e.toString(), Toast.LENGTH_LONG).show();
}
Finally i was able to fix the issues after hours of searching. There were two reasons to this, first is that api was returning null/empty so CustomJsonObjectRequest fixed that, and then another issue is that i forgot to add authentication headers. that was a silly mistake i know!
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
HashMap<String, String> headers = new HashMap<String, String>();
headers.put("Content-Type", "application/json");
headers.put("Authorization", "Bearer "+access_token);
return headers;
}
};
Here is the solution, just create this method and pass your value.
private void CustomJsonObjectRequest() {
String tag_string_req = "req__details";
StringRequest strReq = new StringRequest(Request.Method.POST, <API URL>, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
getPerspective().showErrorLogs(TAG, "Response Invest : " + response);
try {
// Parse your response here
} catch (Exception e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
}) {
#Override
protected Map<String, String> getParams() {
Map<String, String> params = new HashMap<String, String>();
params.put("Id", <ID VALUE HERE>);
params.put("Checked", <TRUE or FALSE>);
return params;
}
};
strReq.setRetryPolicy(new RetryPolicy() {
#Override
public void retry(VolleyError arg0) throws VolleyError {
}
#Override
public int getCurrentTimeout() {
return 0;
}
#Override
public int getCurrentRetryCount() {
return 0;
}
});
strReq.setShouldCache(false);
addToRequestQueue(strReq, tag_string_req);
}
Both ID and Checked must have String type.And create below methods in MainActivity:
private RequestQueue mRequestQueue;
public RequestQueue getRequestQueue() {
if (mRequestQueue == null) {
mRequestQueue = Volley.newRequestQueue(getApplicationContext());
}
return mRequestQueue;
}
public <T> void addToRequestQueue(Request<T> req, String tag) {
req.setTag(TextUtils.isEmpty(tag) ? TAG : tag);
getRequestQueue().add(req);
}
public <T> void addToRequestQueue(Request<T> req) {
req.setTag(TAG);
getRequestQueue().add(req);
}
Question1: How to get response value in onResponse function.
Question2: I create cauHoiArrayList. when I check and get cauHoiArrayList values in onResponse function => it worked. But if I check and get cauHoiArrayList values in GETDATA function ==> it did not work. How to I get cauHoiArrayList values.
Thanks you,
This is my code details:
public void GetCauHoi(String url) {
RequestQueue requestQueue = Volley.newRequestQueue(this);
StringRequest stringRequest = new StringRequest(
Request.Method.POST,
url,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONArray array = new JSONArray(response);
cauHoiArrayList = new ArrayList<>();
for (int i = 0; i < array.length(); i++) {
JSONObject object = array.getJSONObject(i);
_id = object.getInt("_ID");
cauhoi = object.getString("CauHoi");
tenmh = object.getString("TenMH");
tenmonhoc = object.getString("TenMonHoc");
dapan_a = object.getString("DapAn_A");
dapan_b = object.getString("DapAn_B");
dapan_c = object.getString("DapAn_C");
dapan_d = object.getString("DapAn_D");
dapandung = object.getString("DapAnDung");
hinhanh = object.getString("HinhAnh");
dokho = object.getInt("DoKho");
cauHoiArrayList.add(new CauHoi(_id, cauhoi, tenmh, tenmonhoc, dapan_a, dapan_b, dapan_c, dapan_d, dapandung, hinhanh, dokho));
}
Log.d("tag",""+cauHoiArrayList.get(0).getCauHoi());
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(ScreenSlideActivity.this, ""+error, Toast.LENGTH_SHORT).show();
}
}) {
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> params = new HashMap<>();
params.put("laytenmonhocc", "" + laytenmonhoc);
params.put("laydokhoc", "" + laydokho);
return params;
}
};
requestQueue.add(stringRequest);
}
public ArrayList<CauHoi> GETDATA (){
return cauHoiArrayList;
}
Volley requests are asynchronous. You must be calling GETDATA by time when response is not arrived yet. You need to sure call GETGATA when you have response. Only OnResponse method is guarantee that response is present.
I want to get Infos from a Database. When i use a Query without parameters (e.g. "Select * from users;" my script works fine.
Now i have the following script which returns an empty Array. When i replace the $groupId in script with a string value (e.g. "Group1") it returns the expected Items.
<?php
$sql = "";
if($_SERVER['REQUEST_METHOD']== 'POST') {
$flag = array();
$groupId = $_POST['groupId'];
require_once('dbConnect.php');
$sql = "SELECT * FROM users where groupId = '$groupId'";
if($out = mysqli_query($con,$sql)){
//echo "Successfully Registered";
while($row = mysqli_fetch_array($out))
{
$flag[] = $row;
}
print(json_encode($flag));
}else{
echo "Could not register";
}
}else{
echo 'error';
}
//mysqli_close($con);
?>
When i call the following function with the hashmap hashMapGetNames.put("groupId", "Group#1");
then i get an empty array and the info: "No, Group ID is not set"
public ArrayList<String> get(String url, final HashMap<String, String> hashMap, final Context context) {
//Download the items from DB
final ArrayList<String> items = new ArrayList<>();
RequestQueue queue = Volley.newRequestQueue(context);
JSONObject parameters = new JSONObject(hashMap);
final JsonRequest<JSONArray> jsonArrayRequest = new
JsonRequest<JSONArray>(Request.Method.GET, url, parameters.toString(),
new com.android.volley.Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray jsonArray) {
if(jsonArray == null){
Log.d("Downloader", "FAIL: NO NAMES FOUND");
}
else {
for (int zähler = 0; zähler < jsonArray.length(); zähler++){
try {
Log.d("Downloader", "sind bei zähler " + zähler);
JSONObject object = jsonArray.getJSONObject(zähler);
String name = object.getString("name");
Log.d("Name", name);
items.add(name);
}
catch (JSONException e) {
Log.d("Downloader", "Catching exception");
e.printStackTrace();
}
}
}
}
}, new com.android.volley.Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.d("Downloader", "Error: " + error.toString());
}
})
{
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Log.d("Downloader", "gettingParams");
return hashMap;
}
#Override
protected Response<JSONArray> parseNetworkResponse(NetworkResponse response) {
Log.d("Downloader", "parsing Network response");
try {
String jsonString = new String(response.data,
HttpHeaderParser
.parseCharset(response.headers));
Log.d("Downloader", "Parsing success");
return Response.success(new JSONArray(jsonString),
HttpHeaderParser
.parseCacheHeaders(response));
} catch (UnsupportedEncodingException e) {
Log.d("Downloader", e.toString());
return Response.error(new ParseError(e));
} catch (JSONException je) {
Log.d("Downloader", je.toString());
return Response.error(new ParseError(je));
}
}
};
queue.add(jsonArrayRequest);
return items;
}
So the Script seems right but the parameter does not reach the Script. Any Ideas where the error could hide?
EDIT: I edited the code like shown in the tutorial commented below and use the same dbConnect.php file. but it prints out error - so the problem still exist. That means that the Request Method is not "Post".
Android Monitor prints out:
parsing Network response
Downloader: Parsing success
Error: com.android.volley.ParseError: org.json.JSONException: End of input at character 0
try this code...
#Override
protected Map<String, String> getParams() throws AuthFailureError {
//Creating parameters
Map<String,String> params = new Hashtable<String, String>();
//Adding parameters
params.put("groupId", "122");
//returning parameters
return params;
}
EDIT: Figured it out -- see answer below
I'm attempting to generate registration tokens, store them in a server, and then use the tokens to send push notifications. At this point, I've successfully sent and stored registration tokens and am sending notifications from a web API, but they aren't arriving to my device. I was wondering if/what I should replace R.string.gcm_defaultSenderId with (i.e. the sender key from GCM?) I'm including my code for token registration as well as my notification listener below.
public class GCMRegistrationIntentService extends IntentService {
//Constants for success and errors
public static final String REGISTRATION_SUCCESS = "RegistrationSuccess";
public static final String REGISTRATION_ERROR = "RegistrationError";
private Context context;
private String sessionGUID = "";
private String userGUID = "";
//Class constructor
public GCMRegistrationIntentService() {
super("");
}
#Override
protected void onHandleIntent(Intent intent) {
context = getApplicationContext();
sessionGUID = RequestQueueSingleton.getInstance(context).getSessionGUID();
userGUID = RequestQueueSingleton.getInstance(context).getUserGUID();
//Registering gcm to the device
registerGCM();
}
//Registers the device to Google Cloud messaging and calls makeAPICall to send the registration
//token to the server
private void registerGCM() {
//Registration complete intent initially null
Intent registrationComplete;
//declare a token, try to find it with a successful registration
String token;
try {
//Creating an instanceid
InstanceID instanceID = InstanceID.getInstance(this);
//Getting the token from the instance id
token = instanceID.getToken(getString(R.string.gcm_defaultSenderId),
GoogleCloudMessaging.INSTANCE_ID_SCOPE, null);
//Display the token, need to send to server
Log.w("GCMRegIntentService", "token:" + token);
String android_id = Settings.Secure.getString(context.getContentResolver(),
Settings.Secure.ANDROID_ID);
int osTypeCode = Constants.OST_ANDROID;
JSONObject parms = new JSONObject();
try {
parms.put("deviceID", android_id);
parms.put("OSTypeCode", osTypeCode);
parms.put("token", token);
} catch (JSONException e) {
e.printStackTrace();
}
Transporter oTransporter = new Transporter(Constants.TransporterSubjectUSER,
Constants.REGISTER_NOTIFICATION_TOKEN, "", parms, userGUID, sessionGUID);
oTransporter.makeAPICall(getApplicationContext(), "");
//on registration complete. creating intent with success
registrationComplete = new Intent(REGISTRATION_SUCCESS);
//Putting the token to the intent
registrationComplete.putExtra("token", token);
} catch (Exception e) {
//If any error occurred
Log.w("GCMRegIntentService", "Registration error");
registrationComplete = new Intent(REGISTRATION_ERROR);
}
//Sending the broadcast that registration is completed
LocalBroadcastManager.getInstance(this).sendBroadcast(registrationComplete);
}
}
And the listener service:
public class GCMPushReceiverService extends GcmListenerService {
private static final String TAG = "GCMPushReceiverService";
//with every new message
#Override
public void onMessageReceived(String from, Bundle data){
System.out.println("WE'VE RECIEVED A MESSAGE");
String message = data.getString("message");
Log.d(TAG, "From: " + from);
Log.d(TAG, "Message: " + message);
sendNotification(message);
}
private void sendNotification(String message) {
Intent intent = new Intent(this, LogInPage.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
int requestCode = 0;
PendingIntent pendingIntent =
PendingIntent.getActivity(this, requestCode, intent, PendingIntent.FLAG_ONE_SHOT);
Uri sound = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
NotificationCompat.Builder noBuilder = new NotificationCompat.Builder(this);
noBuilder.setContentTitle("title");
noBuilder.setContentText(message);
noBuilder.setContentIntent(pendingIntent);
noBuilder.setSound(sound);
NotificationManager notificationManager =
(NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
notificationManager.notify(0, noBuilder.build()); //0 = ID of notification
}
}
Lastly, as it may be of some assistance, the information transporter/networking class:
public class Transporter {
private String subject;
private String request;
private String key;
private Date lastUpdateDate;
private boolean forceLoad = false;
private Date requestDate;
private Date responseDate;
private int status;
private String statusMsg = "";
private String tempKey = "";
private JSONObject additionalInfo = null;
private JSONObject parameters;
public static String sessionGUID = "";
public static String userGUID = "";
public static String SERVER = Constants.qa_api;
//transporter object to interact with the server, containing information about the request
//made by the user
public Transporter(String pSubject, String pRequest, String pKey,
JSONObject parms, String userGUID, String sessionGUID)
{
subject = pSubject;
request = pRequest;
key = pKey;
parameters = parms;
setUserGUID(userGUID);
setSessionGUID(sessionGUID);
}
//implements an API call for a given transporter, takes 2 arguments:
//the application context (call getApplicationContext() whenever it's called)
//and a String that represents the field that we are trying to update (if there is one)
//i.e. if we are calling getUserFromSession(), we want the user guid so jsonID = "userGUID"
public void makeAPICall(final Context context, final String jsonID) {
RequestQueue mRequestQueue =
RequestQueueSingleton.getInstance(context).getRequestQueue();
String targetURL = getServerURL() + "/Transporter.aspx";
StringRequest postRequest = new StringRequest(Request.Method.POST, targetURL,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
String parseXML= parseXML(response);
System.out.println("response: " + parseXML);
JSONObject lastResponseContent = null;
try {
lastResponseContent = new JSONObject(parseXML);
} catch (JSONException e) {
e.printStackTrace();
}
try {
if (lastResponseContent != null && !jsonID.equals("")) {
String info = lastResponseContent.getString(jsonID);
if (jsonID.equals("userGUID")) {
userGUID = info;
RequestQueueSingleton.getInstance(context).setUserGUID(userGUID);
}
}
//put other things in here to pull whatever info
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
}) {
#Override
public byte[] getBody() throws AuthFailureError {
String body = getXML(subject,
request, "",
sessionGUID, userGUID, null, parameters);
return body.getBytes();
}
};
postRequest.setTag("POST");
mRequestQueue.add(postRequest);
}
you need to send a post to the url "https://android.googleapis.com/gcm/send":
private void sendGCM() {
StringRequest strReq = new StringRequest(Request.Method.POST,
"https://android.googleapis.com/gcm/send", new Response.Listener<String>() {
#Override
public void onResponse(String response) {
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
NetworkResponse networkResponse = error.networkResponse;
Log.e(TAG, "Volley error: " + error.getMessage() + ", code: " + networkResponse);
Toast.makeText(getApplicationContext(), "Volley error: " + error.getMessage(), Toast.LENGTH_SHORT).show();
}
}) {
#Override
protected Map<String, String> getParams() {
Map<String, String> params = new HashMap<>();
params.put("data", "message that you send");
params.put("to", "token gcm");
Log.e(TAG, "params: " + params.toString());
return params;
}
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String,String> headers = new HashMap<String, String>();
headers.put("Content-Type", "application/x-www-form-urlencoded;charset=UTF-8");
headers.put("Authorization", "key="google key");
return headers;
}
};
}
So the Volley calls are non-sequential so the first call (to get a userGUID) didn't return before the second call (to register for notifications), so while the token registration was "successful," there was no corresponding user information so it didn't know how/where to send the push notification. To resolve, I made a special case in the makeAPICall class which created another StringRequest which first basically did the normal getUserFromSession but then recursively called MakeAPICall with the new userGUID information. To avoid an infinite loop, I used an if else statement: (if userGUID == null || userGUID.equals("")) then I did the recursive call, so when the first call returned that conditional was always false and it would only make one recursive call. This answer may be a rambling a bit, but the key take away is using onResponse to make another Volley call for sequential requests. See: Volley - serial requests instead of parallel? and Does Volley library handles all the request sequentially