I'm fairly inexperienced with Android programming and am having issues sending a JSONArray to my PHP server. I am using the following code to generate the JSONArray from my cursor:
public JSONArray matrixJSON(){
Cursor cursor = db.rawQuery("SELECT columnID,rowID,value FROM Matrix WHERE PolicyID=" + curPolicy,null);
JSONArray resultSet = new JSONArray();
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
int totalColumn = cursor.getColumnCount();
JSONObject rowObject = new JSONObject();
for (int i = 0; i < totalColumn; i++) {
if (cursor.getColumnName(i) != null) {
try {
rowObject.put(cursor.getColumnName(i),
cursor.getString(i));
} catch (Exception e) {
Log.d(TAG, e.getMessage());
}
}
}
resultSet.put(rowObject);
cursor.moveToNext();
}
cursor.close();
return resultSet;
}
I believe I am misunderstanding how to properly send data via JsonARrayRequest. Here is the following code that I am using to send the data.
public void sendData(JSONArray data) {
RequestQueue queue = Volley.newRequestQueue(this);
String url = "http://10.123.20.180:8080/insertmatrix.php";
JsonArrayRequest dataReq = new JsonArrayRequest(Request.Method.POST, url, data,
response -> Toast.makeText(MainActivity.this, "Success", Toast.LENGTH_LONG).show(),
error -> Toast.makeText(MainActivity.this, "Error", Toast.LENGTH_LONG).show()){
#Override
protected Response<JSONArray> parseNetworkResponse(NetworkResponse response) {
if (response.data == null || response.data.length == 0) {
return Response.success(null, HttpHeaderParser.parseCacheHeaders(response));
} else {
return super.parseNetworkResponse(response);
}
}
};
queue.add(dataReq);
}
Instead of sending the data, I am left with a blank array. The cursor to JSONarray function is working properly as I can see in debug, but the php server is receiving a blank array. I assume there is some essential functions I am missing.
Fixed it by switching my array into a string and then using a StringRequest to send the data.
Updated function:
public void sendData(JSONArray data) {
RequestQueue queue = Volley.newRequestQueue(this);
String url = "http://10.123.20.180:8080/insertmatrix.php";
String json = data.toString();
StringRequest dataReq = new StringRequest(Request.Method.POST,url,response -> Toast.makeText(MainActivity.this, "Success", Toast.LENGTH_LONG).show(),
error -> Toast.makeText(MainActivity.this, "Error", Toast.LENGTH_LONG).show()){
#Override
protected Map<String,String> getParams(){
Map<String,String> params = new HashMap<String,String>();
params.put("data",json);
return params;
}
};
queue.add(dataReq);
}
Related
Synchronize SQLite With MySql by sending array of ids for the quotes available in the SQLite to php script that will compare it with the available in the database and receive the missing quotes
this method will work in every moment when the app started
btw i know i have mistakes in the php script for that i'm asking now
im facing this error !
D/error: org.json.JSONException: Value Arraynull of type java.lang.String cannot be converted to JSONArray
thank you !
DatabaseHelper.java
public Map<String,String> readIds(){
SQLiteDatabase db=this.getReadableDatabase();
Cursor cursor=db.rawQuery("SELECT * FROM "+TABLE_NAME_QUOTES,null);
Map<String,String> QuotesModuleArray = new HashMap<String, String>();
if (cursor.moveToFirst()){
do {
QuotesModuleArray.put("quote_id"+"["+cursor.getString(0)+"]", cursor.getString(0));
}while (cursor.moveToNext());
}
cursor.close();
return QuotesModuleArray;
}
MainActivity.java
public void Quotes_SQLITE() throws UnsupportedEncodingException {
String url=".../android/checkquotes.php";
Map<String,String> arrayListQuotes;
dbHandler = new DataBaseHelper(MainActivity.this);
arrayListQuotes = dbHandler.readIds();
System.out.println(Arrays.toString(new Map[]{arrayListQuotes}));
quotesListSQLite.clear();
JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(Request.Method.GET, url, null,
response -> {
Log.e("Quotesqlite : ",response.toString());
progressBar.setVisibility(View.GONE);
swipeRefreshLayout.setRefreshing(false);
for (int i = 0 ; i < response.length() ; i++){
try {
JSONObject jsonObject = response.getJSONObject(i);
int quote_id = jsonObject.getInt("quote_id");
String quote_name = jsonObject.getString("quote_name");
String quote_details = jsonObject.getString("quote_details");
String status = jsonObject.getString("status");
String parent_id = jsonObject.getString("parent_id");
int language_id = jsonObject.getInt("language_id");
QuoteSQLite quote = new QuoteSQLite(quote_id , quote_name , quote_details , status,parent_id, language_id);
dbHandler.Add_Quote(quote_id,quote_name,quote_details, status,parent_id, language_id);
quotesListSQLite.add(quote);
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(context, error.getMessage()+"", Toast.LENGTH_SHORT).show();
Log.d("error",error.getMessage()+"");
if((error.getMessage()+"").equals("null")) {
try {
Quotes_SQLITE();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
}
})
{
#Override
protected Map<String, String> getParams() {
Map<String, String> params;
params=arrayListQuotes;
return params;
}
};
requestQueue.add(jsonArrayRequest);
}
PHP Script
<?php
header('Content-Type: application/json; charset=utf-8');
define('DB_HOST', 'localhost');
define('DB_USER', 'ibnabita_alihaydar');
define('DB_PASS', '81336874');
define('DB_NAME', 'ibnabita_secure_imam');
$conn = mysqli_connect(DB_HOST, DB_USER, DB_PASS, DB_NAME);
mysqli_query($conn,"SET NAMES 'utf8'");
mysqli_query($conn,'SET CHARACTER SET utf8');
$allarray = array();
$toaddarray = array();
$flag = [];
$i = 0 ;
if(mysqli_connect_error($conn))
{
echo "Failed to connect to database ".mysqli_connect_error();
}
$sql="select quote_id from quotes";
$result2=mysqli_query($conn,$sql);
if($result2)
{
while($row=mysqli_fetch_array($result2,MYSQLI_BOTH))
{
array_push($allarray,$row["quote_id"]);
}
}
$ids = array();
foreach($_POST as $key=>$value){
$ids[] = $_POST[$key];
}
$data = json_decode($ids,true);
foreach($data as $item) { //foreach element in $arr
echo $item."\n" ;
}
foreach($allarray as $item) { //foreach element in $arr
//echo $item."\n" ;
if(in_array( $item ,$data))
{
}
else
{
$sql23="select * from quotes where quote_id=".$item;
$result23=mysqli_query($conn,$sql23);
$row23=mysqli_fetch_array($result23,MYSQLI_BOTH);
$flag[]=$row23;
}
}
print(json_encode($flag,JSON_UNESCAPED_UNICODE));
mysqli_close($conn);
?>
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;
}
I am creating class which should send JSONArrayRequest using volley with specific params, then find mysql rows which equals these params and send it back. I wrote simple mysql function which receive POST params and Java method which send and receive JSONObjects. But it isn't working and I receive nothing.
This is my PHP file called details.php. It receive parameters from my Android App and send back an array.
require_once __DIR__ . '/db_connect.php'
$db = new DB_CONNECT();
$path= $_POST["path"];
$result = mysql_query("SELECT * FROM modx_ms2_product_files WHERE path = $path") or die(mysql_error());
// check for empty result
if (mysql_num_rows($result) > 0) {
// looping through all results
// products node
$json_response = array();
while ($row = mysql_fetch_array($result)) {
// temp user array
$product = array();
$product ["file"] = $row["file"];
// push single product into final response array
array_push($json_response, $product);
}
// echoing JSON response
echo json_encode($json_response);
$conn->close();
}
This is my method getArray(), which send request and receive response:
public void getarray() {
String path = "1578/";
final String URL = "http://myurl.io/details.php";
HashMap<String, String> params = new HashMap<String, String>();
params.put("path", path);
JsonArrayRequest customarray = new JsonArrayRequest(Request.Method.POST,URL,new JSONObject(params),new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
if (response.length() > 0) {
// Parsing json
for (int i = 0; i < response.length(); i++) {
try {
JSONObject Obj = response.getJSONObject(i);
pics pic = new pics();
pic.setFile(Obj.getString("file"));
Log.i("cmon", Obj.getString("file"));
pics.add(pic);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
AppController.getInstance().addToRequestQueue(customarray);
}
This is my modx_ms2_product_files table:
http://i.imgur.com/yl1f7Ze.png
http://i.imgur.com/9V6PrBU.png
Have you tried using StringRequest? For some reason when i used JsonArrayRequest i didn't get any response back from the server. If you decide to create a StringRequest you could convert your response to a JSONArray like this:
StringRequest get = new StringRequest(Method.POST, URL, new Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONArray myArray = new JSONArray(response);
for(int i = 0; i < myArray.length(); i++)
{
JSONObject jObj = myArray.getJSONObject(i);
// get your data here
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
Then of course add your request to the request queue.
I'm using Volley however I'm having some problems with the JSON parsed data most likely because volley doesn't implement something like AsyncTask's onPostExecute() and I'm getting some duplicated data on wrong list items.
Then I came across this: https://github.com/yakivmospan/volley-request-manager#custom-listener-implementation-
Has anyone use it? How can I add it to my current Volley code?
More details about my problem here Volley not sending correct data. How to implement an alternative to onPostExecute()?
UPDATE
As requested, some code. Here's a button that calls a method on another class that uses Volley to request some raw JSON data (NovaJSON) and then send the JSON to a parser class (NovaParser):
info.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String instanceDetail = NovaJSON.shared().receiveDetail(getId());
Dialog dialog = new Dialog(v.getContext());
dialog.setContentView(R.layout.instances_info);
TextView image = (TextView) dialog.findViewById(R.id.imageInstance);
TextView flavor = (TextView) dialog.findViewById(R.id.flavorInstance);
dialog.setTitle(name.getText() + " Details");
if (instanceDetail != null) {
image.setText(" \u2022 image : " + NovaParser.shared().parseImages(instanceDetail));
flavor.setText(" \u2022 flavor : " + NovaParser.shared().parseFlavor(instanceDetail));
}
dialog.show();
}
});
This is the method that does the Volley request on the NovaJSON class:
public void getJSONdetail() {
final String authToken = getAuth();
String novaURL = getNova();
novaURL = novaURL+"/servers/"+id;
JsonObjectRequest getRequest = new JsonObjectRequest(Request.Method.GET, novaURL, null,
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
Log.d("Nova on Response", response.toString());
setNovaJSONdetail(response.toString());
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
VolleyLog.d("Nova on Error", "Error: " + error.getMessage());
setNovaJSONdetail(error.toString());
}
}
) {
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String, String> params = new HashMap<String, String>();
params.put("X-Auth-Token", authToken);
params.put("User-Agent", "stackerz");
params.put("Accept", "application/json");
params.put("Content-Type", "application/json; charset=utf-8");
return params;
}
};
queue = VolleySingleton.getInstance(this).getRequestQueue();
queue.add(getRequest);
}
It then sends the JSON from the server as a string to be parsed using the following methods:
public static String parseImages(String imagesDetail){
ArrayList<HashMap<String, String>> imagesList = NovaParser.shared().getImagesList();
String temp = null;
JSONObject novaDetail = null;
try {
novaDetail = new JSONObject(imagesDetail);
JSONObject server = novaDetail.getJSONObject("server");
JSONObject image = server.getJSONObject("image");
if (imagesList !=null){
temp = image.getString("id");
for (Map<String,String> map : imagesList) {
if (map.containsValue(temp)) {
temp = map.get(NAME);
}
}
}
} catch (JSONException e) {
e.printStackTrace();
}
return temp;
}
public static String parseFlavor(String instanceDetail){
ArrayList<HashMap<String, String>> flavorList = NovaParser.shared().getFlavorList();
String temp = null;
JSONObject novaDetail = null;
try {
novaDetail = new JSONObject(instanceDetail);
JSONObject server = novaDetail.getJSONObject("server");
JSONObject flavor = server.getJSONObject("flavor");
if (flavorList !=null){
temp = flavor.getString("id");
for (Map<String,String> map : flavorList) {
if (map.containsValue(temp)) {
temp = map.get(NAME);
}
}
}
} catch (JSONException e) {
e.printStackTrace();
}
return temp;
}
When I press the button once the dialog is displayed with empty values. When I press it the second time I get the correct parsed data. Basically first time I click the button the instanceDetail string is null because Volley didn't finish doing its thing then I click the 2nd time it loads the values accordingly because it finally finished the 1st request.
I understand Volley is asynchronous, the requests happen in parallel and the responses sometimes are not immediate however I need some sort of progress bar or spinning wheel to give the user some feedback that the app is waiting for data. It could be done with AsyncTask however it doesn't seem to be possible with Volley.
I think your problem is not because of Volley.
Check the parameters you send and receive.
However if you need onPostExcecute you have Volley's callback:
Response.Listener<JSONObject> and Response.ErrorListener() which are called after the request.
About Volley request manager just switch all your volley calls with appropriate Volley request manager calls
I solved my problem by dumping Volley altogether and moving to Retrofit. I setup all the calls to be sync/blocking, worked out the exceptions/errors using try/catches and setup a short timeout on the OkHTTP client. Now it's working as I wanted.