Develop Reference

Next Page Token is not functional and display only maximum (50) results

I am trying to fetch all videos of a channel using youtube data api, but my code is giving error and doesn't respond to PAGE token
displayVideos();
}
private void displayVideos ()
{
RequestQueue requestQueue= Volley.newRequestQueue(this);
StringRequest stringRequest=new StringRequest(Request.Method.GET, url, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONObject jsonObject = new JSONObject(response);
System.out.println(jsonObject.get("nextPageToken"));
JSONArray jsonArray = jsonObject.getJSONArray("items");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObject1 = jsonArray.getJSONObject(i);
if (jsonObject1.has("id")){
JSONObject jsonVideoId=jsonObject1.getJSONObject("id");
if (jsonVideoId.has("kind")){
if(jsonVideoId.getString("kind").equals("youtube#video")){
JSONObject jsonObjectSnippet = jsonObject1.getJSONObject("snippet");
JSONObject jsonObjectDefault=jsonObjectSnippet.getJSONObject("thumbnails").getJSONObject("medium");
String video_id=jsonVideoId.getString("videoId");
VideoDetails vd=new VideoDetails();
vd.setVideoId(video_id);
vd.setTitle(jsonObjectSnippet.getString("title"));
vd.setDescription(jsonObjectSnippet.getString("description"));
vd.setUrl(jsonObjectDefault.getString("url"));
videoDetailsoArrayList.add(vd);
}
// recyclerView.setAdapter(adapter);
// adapter.notifyDataSetChanged();
}
}
}
}catch (JSONException e) {
e.printStackTrace();
}
the url I am trying to parse is
String url="https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=UCVMWWQ985A_-SESZUy_SsVQ&maxResults=50&pageToken="+nextPageToken+"&order=date&pageToken=CAUQAA&key=API_KEY";
I have been searchingb to apply nextpage token or page token in android studio but couldnt get specific tutorial. there are many examples but being naive in android studio I cant implement it into my code.

Please note that your URL does contain two instances of the parameter pageToken:
"https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=UCVMWWQ985A_-SESZUy_SsVQ&maxResults=50&pageToken="+nextPageToken+"&order=date&pageToken=CAUQAA&key=API_KEY".
It should have only one for that to work OK; to be more precise, your URL should contain only this instance: pageToken="+nextPageToken+".
On the other hand, your code above does not show the loop implementing pagination. That is that you haven't shown the piece of code where you actually assign a valid value to the variable nextPageToken.
Therefore I cannot tell if your program will work or not.
The pagination loop would look like this:
// initially no pageToken
nextPageToken = null;
// URL as above, without the parameter pageToken
url = ...
do {
invoke the API on the URL: url + (nextPageToken != null ? "&pageToken=" + nextPageToken : "")
nextPageToken = jsonObject.get("nextPageToken");
} while (nextPageToken != null)

How to find specific data from a Volley Api string response

I am new to APIs and finally figured out how to successfully retrieve a request response from a website. The thing is I am completely lost on how I should handle the response. I don't know how to access certain values within the response
here is my API Volley code
RequestQueue requestQueue = Volley.newRequestQueue(this);
String uri = Uri.parse("https://chicken-coop.p.rapidapi.com/games/Fortnite?platform=pc")
.buildUpon()
.build().toString();
StringRequest stringRequest = new StringRequest(
Request.Method.GET, uri, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
displayResults.setText("Response: " + response.substring(0,500));
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
displayResults.setText( "" + error.toString());
}
}) {
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String, String> params = new HashMap<>();
params.put("X-RapidAPI-Key", "5cdb2bbe57mshd9242c8d3177cb3p16f2fbjsnd7c5829eb4ad");
params.put("X-RapidAPI-Host", "chicken-coop.p.rapidapi.com");
return params;
}
};
requestQueue.add(stringRequest);
Here is the response query that I received
"result":{10 items
"title":"Fortnite"
"releaseDate":"Jul 25, 2017"
"description":"Epic Games next project has you building forts and stopping a zombie invasion."
"genre":[...
]6 items
"image":"https://static.metacritic.com/images/products/games/5/c7eb46ceb7da9c72c5a95193e8621faf-98.jpg"
"score":81
"developer":"Epic Games"
"publisher":[...
]1 item
"rating":"T"
"alsoAvailableOn":[6 items
0:
"iPhone/iPad"
1:
"PlayStation 3"
2:
"PlayStation 4"
3:
"Switch"
4:
"Xbox 360"
5:
"Xbox One"
How would I go about finding an explicit value from the response query? I have been searching for how to do this online and there are so many different ways to go about and I have no clue what to do. For example, how would I be able to put the Release Date into its own text box? Most of the examples I see online use JsonObjects when I m using a string response

in your onResponse method you need to parse your result so you can extract any data you want
public void onResponse(String response) {
try {
JSONObject jsonObject = new JSONObject(response);
JSONArray jsonArray = jsonObject.getJSONArray("result");
// toaccess to your json data
String title = jsonArray.getString("title");
// your code
} catch (JSONException e) {
e.printStackTrace();
}
}

Get JSONArray with StringRequest from Android

I am trying to get hold of a JSONArray by using StringRequest in Android along with the POST-method.
The php-script is written like:
$statement = mysqli_prepare($con, "SELECT * FROM tickets WHERE user_id > 5 AND completed = 1");
mysqli_stmt_bind_param($statement, "i", $UID);
mysqli_stmt_execute($statement);
mysqli_stmt_store_result($statement);
mysqli_stmt_bind_result($statement, $user_id, $beacon_id, $timeFrom, $timeTo, $completed);
$jsonObject = array();
$response = array();
while($status = mysqli_stmt_fetch($statement)){
$jsonObject = null;
$jsonObject["beacon_id"]= $beacon_id;
$jsonObject["timeFrom"]= $timeFrom;
$jsonObject["timeTo"]= $timeTo;
$response[] = $jsonObject;
}
echo json_encode($response);?>
Accessing the web-page with the php-script, the following JSONArray is "echoed":
[{"beacon_id":10,"timeFrom":"2018-02-14 13:07:11","timeTo":"2018-02-14 14:32:53"},{"beacon_id":3,"timeFrom":"2018-02-24 13:33:37","timeTo":"2018-02-24 13:33:47"}]
And as I understand this is a normal JSONArray with square-brackets representing the array and curly-brackets for each JSONObject inside the array.
When I try to access this JSONArray through a StringRequest in Android Studio (Java), I do not get any results...
The StringRequest code:
public class HistoryRequest extends StringRequest {
private static final String HISTORY_REQUEST_URL = "http://myURL.../myPHPfile.php";
private Map<String, String> params;
public HistoryRequest(String user_id, String instanceID, Response.Listener<String> listener) {
super(Method.POST, HISTORY_REQUEST_URL, listener, null);
params = new HashMap<>();
params.put("user_id", user_id);
params.put("instanceID", instanceID);
}
#Override
public Map<String, String> getParams() {return params;}
}
The ResponseListener in the MainActivity is written like:
Response.Listener<String> responseListener = new Response.Listener<String>() {
#Override
public void onResponse(String response) {
JSONArray jsonArray = new JSONArray(response);
for(int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObject = jsonArray.getJSONObject(i);
String timeFrom = jsonObject.getString("timeFrom");
String timeTo = jsonObject.getString("timeTo");
textviewFrom.append(timeFrom);
textviewTo.append(timeTo);
}
}
};
Any tips why I can't make a JSONArray of the String that in the web-page URL looks like a beautiful JSONArray?
Thanks in advance!
UPDATE:
After switching to JSONArrayRequest instead of StringRequest, I can get the data if I change the MySQL part of the php-script to something static like:
SELECT * FROM tickets;
Then I can display all the entries. But I tend to send 1 parameter to the server (user_id), so that I can filter the entries based on the user that is logged in. [SELECT * FROM tickets where user_id = ?], like a traditional POST-method....
Someone who knows what to do? Read several places that you can not #Override the getParams()-method for this...
SOLVED:
I solved the issue by entering the keyvalue (user_id) into the URL.
//Instead of POST:
$user_id = $_POST["user_id"];
// I use SERVER to get the value after ? in the URL:
$user_id = $_SERVER['QUERY_STRING'];
Doing this with the following java-code:
public class HistoryRequest extends JsonArrayRequest {
private static final String HISTORY_REQUEST_URL = "http://myURLorIPaddress/getHistory.php?";
public HistoryRequest(String UID, Response.Listener<JSONArray> listener) throws JSONException {
super(Method.POST, HISTORY_REQUEST_URL + UID,null, listener, null);
}
}
This made it possible to filter the result based on user_id and works like a charm :D

I do not get to print anything, but I can see that the Volley library is complaining for some external errors (nothing referred to my code). The log.i("OnResponseLog", response) does not provide anything.
Picture of error from LogCat:

I am working in similar project did you check if there are some null entries? I think the problem might be there by checking your LogCat picture.
Check using isNull() function might be good idea.
https://processing.org/reference/JSONObject_isNull_.html

org.json.JSONException: End of input at character 0 of

There is some issue with the JSONObjectRequest in Volley library to receive the JSON data. I suppose I am going wrong somewhere in receiving the JSON object in the Java code. Following is my JSON output coming as a response from the php file hosted on server:
{"workers":[
{"id":"1","name":"Raja","phonenumber":"66589952","occupation":"Plumber","location":"Salunke Vihar","rating":"4","Review":"Hard Worker","price":"80"},
{"id":"2","name":"Aman","phonenumber":"789456","occupation":"Plumber","location":"Wakad","rating":"4","Review":"Good","price":"80"}
],
"success":1}
Following is clode from the Java file where I am using the JSON request using Volley library:
JsonObjectRequest jsonRequest = new JsonObjectRequest (Request.Method.POST, url,
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try {
// I should receive the success value 1 here
int success = response.getInt("success");
//and should receive the workers array here
Log.d("response",response.getJSONArray("workers").toString());
Log.d("success",""+success);
} catch (JSONException e) {
e.printStackTrace();
}
Toast.makeText(getApplicationContext(), response.toString(), Toast.LENGTH_LONG).show();
recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
recyclerView.setHasFixedSize(true);
layoutManager = new LinearLayoutManager(getApplicationContext());
recyclerView.setLayoutManager(layoutManager);
//Finally initializing our adapter
adapter = new WorkerAdapter(listWorkers);
recyclerView.setAdapter(adapter);
//adapter is working fine
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.d("error",error.toString());
Toast.makeText(getApplicationContext(),error.toString(),Toast.LENGTH_LONG).show();
}
}){
#Override
protected Map<String,String> getParams(){
Map<String,String> params = new HashMap<String, String>();
params.put("tag", "get_list");
params.put("service", service);
return params;
}
Running the above code it goes to the error listener and gives the output as org.json.JSONException: End of input at character 0 of.
But if I use StringRequest in place of JsonObjectRequest and receive the JSON response as a string then I am able to receive the output as a String but I can't use it further. So, please let me know where I am going wrong in receiving the JSONdata and suggest me the changes in the code that I must do.
EDIT- I am adding the php file which is returning the JSON object. Please let me know if there is some error over here:
<?php
error_reporting(0);
include("config.php");
if($_SERVER['REQUEST_METHOD']=='POST'){
$tag = $_POST['tag'];
// array for JSON response
$response = array();
if ($tag == 'get_list') {
// Request type is check Login
$service = $_POST['service'];
//echo json_encode($service);
// get all items from myorder table
$result = mysql_query("SELECT * FROM Workers WHERE Occupation = '$service'") or die(mysql_error());
if (mysql_num_rows($result) > 0) {
$response["workers"] = array();
while ($row = mysql_fetch_array($result)) {
// temp user array
$item = array();
$item["id"] = $row["wID"];
$item["pic"] = $row["Pic"];
$item["name"] = $row["Name"];
$item["phonenumber"] = $row["Phone Number"];
$item["occupation"] = $row["Occupation"];
$item["location"] = $row["Location"];
$item["rating"] = $row["Rating"];
$item["Review"] = $row["Review"];
$item["price"] = $row["Price"];
// push ordered items into response array
array_push($response["workers"], $item);
}
// success
$response["success"] = 1;
}
else {
// order is empty
$response["success"] = 0;
$response["message"] = "No Items Found";
}
}
echo json_encode($response);
}
?>

When I ran the api end point I have got the following result instead of the one that you have been telling so. So stop giving irrelevant data.
"Plumber"{"workers":[{"id":"1","pic":"ttp:\/\/vorkal.com\/images\/vorkal_cover.PNG","name":"Raja","phonenumber":"66589952","occupation":"Plumber","location":"Salunke Vihar","rating":"4","Review":"Hard Worker. Very Professional.","price":"80"},{"id":"2","pic":"http:\/\/vorkal.com\/images\/vorkal_cover.PNG","name":"Aman","phonenumber":"789456","occupation":"Plumber","location":"Wakad","rating":"4","Review":"Good","price":"80"}],"success":1}
Where Plumber is not the tag at all, hence throws error as the same is not valid json string. There's error in your server side scripting. I request you to send the complete script without modification.
If you are not getting the JSONObject that means the following is a malformed json. Thus you can try the following code in server side
function utf8ize($d) {
if (is_array($d)) {
foreach ($d as $k => $v) {
$d[$k] = $this->utf8ize($v);
}
} else if (is_string ($d)) {
return utf8_encode($d);
}
return $d;
}
where$d is the string/response. use it as echo json_encode($this->utf8ize($detail));
Also try the following in client side code
Gson gson = new Gson();
JsonReader reader = new JsonReader(new StringReader(result1));
reader.setLenient(true);
You may refer the solution to this question here click here

you can use Gson to convert json string to object
Gson gson = new Gson();
GetWorkersResponse getWorkersResponse =gson.fromJson(response,GetWorkersResponse.class);
class GetWorkersResponse {
public boolean success;
public List<Worker> workers = new ArryList<>();
}
It's work for me.

Can you check that server is returning you a JSONObject and not the string? In Volley if the type of response is different then it will return the error.

How do i split a string of jsonObjects into an array

I'm getting some data from the Trello API over HTTP. So an example of the response would be:
'[{"name":"asd","desc":"yes"},{"name":"xyz","desc":"no"}]'
I'm using the volley library for making the request and getting the response. Is there a way for me to get the response in the form of json objects directly instead of in a string?
If not how should I proceed?
Thanks!

You can use JSONArray(). And then you can use getString() so you can use all string function.
Example code:
JSONArray jsonArray = new JSONArray(responseString);
int i = 0;
while (i <jsonArray.length()) {
JSONObject jsonObj = jsonArray.getJSONObject(i);
String name = jsonObj.getString("name");
String description = jsonObj.getString("desc");
//TODO create your Java object and store these strings into it.
i++;
}

use volley can solve easily.
JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(url,new Response.Listener<JSONArray>(){
#Override
public void onResponse(JSONArray response) {
//the response is JsonArray
}
},new Response.ErrorListener(){
#Override
public void onErrorResponse(VolleyError error) {
}
});