Develop Reference

POST JSON data to server

I am working on POST JSON data to server. It is working fine with a tutorial this link but it is not working with this with some of the required data changes. Is there anything related to Javaservlet and PHP links , as the first link is designed using Javasevlet and the other is in PHP ?
public static String POST(String url)
{
InputStream inputStream = null;
String result = "";
try {
org.apache.http.client.HttpClient httpClient=new DefaultHttpClient();
HttpPost httpPost=new HttpPost(url);
String json = "";
JSONObject jsonObject=new JSONObject();
/*JSONArray jsonArray=jsonObject.getJSONArray("object");
JSONObject jsonObject2=jsonArray.getJSONObject(10);*/
jsonObject.putOpt("id",2);
jsonObject.putOpt("address","myaddress");
json=jsonObject.toString();
StringEntity se=new StringEntity(json);
httpPost.setEntity(se);
httpPost.setHeader("Accept", "application/json");
httpPost.setHeader("Content-type", "application/json");
HttpResponse httpResponse=httpClient.execute(httpPost);
inputStream = httpResponse.getEntity().getContent();
// 10. convert inputstream to string
if(inputStream != null)
result = convertInputStreamToString(inputStream);
else
result = "Did not work!";
} catch (JSONException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return result;
}
private class HttpAsyncTask extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... urls) {
// person = new PersonLocator();
// person.setAddresS(myLocationText.getText().toString());
return POST(urls[0]);
}
// onPostExecute displays the results of the AsyncTask.
#Override
protected void onPostExecute(String result) {
Toast.makeText(getBaseContext(), "Data Sent!", Toast.LENGTH_LONG).show();
}
}
Thanks for the help in advance

Why doesn't the function get data from php in android?

I want to get response after post data but it fails. I want to create a login system, I have successfully submited data to php file, everything is working fine now I want to get response from same function but I'm unable to know where the issue is.
Here is the Java function:
public class PostDataGetRes extends AsyncTask<String, String, String> {
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected String doInBackground(String... strings) {
try {
postRData();
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String lenghtOfFile) {
// do stuff after posting data
}
}
public void postRData() {
String result = "";
InputStream isr = null;
final String email = editEmail.getText().toString();
final String pass = editPass.getText().toString();
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://website.com/appservice.php");
try {
// Add your data
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
nameValuePairs.add(new BasicNameValuePair("id", email));
nameValuePairs.add(new BasicNameValuePair("stringdata", pass));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
resultView.setText("Inserted");
HttpEntity entity = response.getEntity();
isr = entity.getContent();
//convert response to string
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(isr,"iso-8859-1"),8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
isr.close();
result=sb.toString();
}
catch(Exception e){
Log.e("log_tag", "Error converting result "+e.toString());
}
//parse json data
try {
String s = "";
JSONArray jArray = new JSONArray(result);
for(int i=0; i<jArray.length();i++){
JSONObject json = jArray.getJSONObject(i);
s = s +
"Name : "+json.getString("first_name")+"\n\n";
//"User ID : "+json.getInt("user_id")+"\n"+
//"Name : "+json.getString("first_name")+"\n"+
//"Email : "+json.getString("email")+"\n\n";
}
resultView.setText(s);
} catch (Exception e) {
// TODO: handle exception
Log.e("log_tag", "Error Parsing Data "+e.toString());
}
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
} catch (IOException e) {
// TODO Auto-generated catch block
}
resultView.setText("Done");
}
And here is php code:
if($id){
$query = mysql_query("SELECT first_name FROM users where email = '$id' ");
while($row=mysql_fetch_assoc($query)){
$selectedData[]=$row;
}
print(json_encode($selectedData));
}
Please help me I have tried so far but could not achieve any results. Please help me how can I get response from php file after query execution.

At first be sure you get correct JSON object from your website - try printing it as Toast.makeText(). As far the web browsers keep the html comments away, android gets it in response.
AsyncTask objects and classes aren't designed to be made the way u provided and also you can't make any UI operations in doInBackground(). AsyncTask is made in a way to not to block GUI.
Here is a not much different example how it uses methods you have in AsyncTask class:
class Logging extends AsyncTask<String,String,Void>{
JSONObject json=null;
String output="";
String log=StringCheck.buildSpaces(login.getText().toString());
String pas=StringCheck.buildSpaces(password.getText().toString());
String url="http://www.mastah.esy.es/webservice/login.php?login="+log+"&pass="+pas;
protected void onPreExecute() {
Toast.makeText(getApplicationContext(), "Operation pending, please wait", Toast.LENGTH_SHORT).show();
}
#Override
protected Void doInBackground(String... params) {
HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet(url);
request.addHeader("User-Agent", "User-Agent");
HttpResponse response;
try {
response = client.execute(request);
BufferedReader br = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
String line="";
StringBuilder result = new StringBuilder();
while ((line = br.readLine()) != null) {
result.append(line);
}
output=result.toString();
} catch (ClientProtocolException e) {
Toast.makeText(getApplicationContext(), "Connection problems", Toast.LENGTH_LONG).show();
} catch (IOException e) {
Toast.makeText(getApplicationContext(), "Conversion problems", Toast.LENGTH_LONG).show();
}
return null;
}
#Override
protected void onPostExecute(Void w) {
try {
json = new JSONObject(output);
if(json.getInt("err")==1){
Toast.makeText(getApplicationContext(), json.getString("msg"), Toast.LENGTH_LONG).show();
}else{
String id_user="-1";
Toast.makeText(getApplicationContext(), json.getString("msg"), Toast.LENGTH_LONG).show();
JSONArray arr = json.getJSONArray("data");
for(int i =0;i<arr.length();i++){
JSONObject o = arr.getJSONObject(i);
id_user = o.getString("id_user");
}
User.getInstance().setName(log);
User.getInstance().setId(Integer.valueOf(id_user));
Intent i = new Intent(getApplicationContext(),Discover.class);
startActivity(i);
}
} catch (JSONException e) {
}
super.onPostExecute(w);
}
}
PHP file content:
$data = array(
'err' => 0,
'msg' => "",
'data' => array(),
);
$mysqli = new MySQLi($dbhost,$dbuser,$dbpass,$dbname);
if($mysqli->connect_errno){
$data['err'] = 1;
$data['msg'] = "Brak polaczenia z baza";
exit(json_encode($data));
}
if(isset($_GET['login']) && isset($_GET['pass'])){
$mysqli->query("SET CHARACTER SET 'utf8';");
$query = $mysqli->query("SELECT banned.id_user FROM banned JOIN user ON user.id_user = banned.id_user WHERE user.login ='{$_GET['login']}' LIMIT 1;");
if($query->num_rows){
$data['err']=1;
$data['msg']="User banned";
exit(json_encode($data));
}else{
$query = $mysqli->query("SELECT login FROM user WHERE login='{$_GET['login']}' LIMIT 1;");
if($query->num_rows){
$query = $mysqli->query("SELECT pass FROM user WHERE pass ='{$_GET['pass']}' LIMIT 1;");
if($query->num_rows){
$data['msg']="Logged IN!";
$query = $mysqli->query("SELECT id_user FROM user WHERE login='{$_GET['login']}' LIMIT 1;");
$data['data'][]=$query->fetch_assoc();
exit(json_encode($data));
}else{
$data['err']=1;
$data['msg']="Wrong login credentials.";
exit(json_encode($data));
}
}else{
$data['err']=1;
$data['msg']="This login doesn't exist.";
exit(json_encode($data));
}
}
}else{
$data['err']=1;
$data['msg']="Wrong login credentials";
exit(json_encode($data));
}
I have created there small dictionary $data for my app. I used its err key as a flag to know if any error appeared, msg to inform user about operation results and data to send JSON objects.
Thing you would want to do with if(response == true) if it had exist is similar to construction i used in my onPostExecute(Void w) method in AsyncTask:
if(json.getInt("err")==1){
//something went wrong
}else{
//everything is okay, get JSON, inform user, start new Activity
}
Also here is the way I used $data['data'] to get JSON response:
if($query->num_rows){
while($res=$query->fetch_assoc()){
$data['data'][]=$res;
}
exit(json_encode($data));
}

Android: JSONParser returns NullPointerException

I've read many other topics on SO from people who received the same exception, but none of the proposed solutions worked. So here's my problem:
I'm trying to download a userlist from my database through a function in my app. The JSONParser keeps returning a NullPointException on this particular table from the database. I've successfully used the JSONParser class on other queries, but it doesn't work on this one. I've tested the PHP file which handles the query, and it returns the exact values I want as a JSON OBject. If the table is empty, it returns:
{
"success":0,
"message":"No users found"
}
If the table contains user information, it returns:
{
"success":1,
"users":[
{
"ID":someID1,
"NAME":someName1
"PHONE":somePhoneNumber1
},
{
"ID":someID2,
"NAME":someName2
"PHONE":somePhoneNumber2
}]
}
I'm starting the request by calling
LoadAllUsers load = new LoadAllUsers();
load.execute();
in a certain method. This is my LoadAllUsers class:
public class LoadAllUsers extends AsyncTask<Void, Void, Boolean> {
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(allUsers.this);
pDialog.setMessage("Laden van alle gebruikers...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
#Override
protected Boolean doInBackground(Void... args) {
updateJSONData();
return null;
}
#Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
pDialog.dismiss();
updateList();
}
}
I receive a NullPointerException on the first line of my updateJSONdata() method, which is:
public void updateJSONData() {
JSONObject json = jParser.getJSONFromUrl(my_url);
try {
int success = json.getInt("success");
if (success == 1) {
JSONArray users = json.getJSONArray("users");
for (int i = 0; i<users.length(); i++) {
JSONObject c = users.getJSONObject(i);
String id = c.getString("ID");
String name = c.getString("NAAM");
String phone =c.getString("TELEFOON");
HashMap<String,String> map = new HashMap<String, String>();
map.put("ID",id);
map.put("name",name);
map.put("phonenumber",phone);
if (phoneNumber == phone) {
ID = Integer.parseInt(id);
this.name = name;
}
userlist.add(map);
}
} else {
Log.d("Geen succes!", "Helaas!");
}
} catch (JSONException e) {
e.printStackTrace();
}
}
So, the exception is thrown in the line with jParser.getJSONFromUrl(...).
My JSONParser class, of which jParser is an instance, is:
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
public JSONParser() {
}
public JSONObject getJSONFromUrl(final String url) {
// Making HTTP request
try {
// Construct the client and the HTTP request.
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
// Execute the POST request and store the response locally.
HttpResponse httpResponse = httpClient.execute(httpPost);
// Extract data from the response.
HttpEntity httpEntity = httpResponse.getEntity();
// Open an inputStream with the data content.
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
// Create a BufferedReader to parse through the inputStream.
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
// Declare a string builder to help with the parsing.
StringBuilder sb = new StringBuilder();
// Declare a string to store the JSON object data in string form.
String line = null;
// Build the string until null.
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
// Close the input stream.
is.close();
// Convert the string builder data to an actual string.
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// Try to parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// Return the JSON Object.
return jObj;
}
// function get json from url
// by making HTTP POST or GET mehtod
public JSONObject makeHttpRequest(String url, String method,
List<NameValuePair> params) {
// Making HTTP request
try {
// check for request method
if(method == "POST"){
// request method is POST
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}else if(method == "GET"){
// request method is GET
DefaultHttpClient httpClient = new DefaultHttpClient();
String paramString = URLEncodedUtils.format(params, "utf-8");
Log.d("Gemaakte paramstring",paramString);
url += "?" + paramString;
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
Log.d("httpResponse: ",httpResponse.toString());
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}
And the LogCat message is:
05-07 10:46:24.995 27615-27686/com.example.user.my_app E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
Process: com.example.user.my_app, PID: 27615
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:300)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:841)
Caused by: java.lang.NullPointerException
at com.example.user.my_appcenter_tile.updateJSONData(center_tile.java:376)
at com.example.user.my_app.center_tile$Memberlist.doInBackground(center_tile.java:419)
at com.example.user.my_app.center_tile$Memberlist.doInBackground(center_tile.java:406)
at android.os.AsyncTask$2.call(AsyncTask.java:288)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:841)
I would be very grateful if you could help me out with this problem.

Well, jParser is null in updateJSONdata().
Make sure to check if it's != null before using it.
And if it should not be null, then fix your code.
Your error is just a NullPointerException.

You can use 'has' keyword to check availability of json keys, then can parse Json to avoid exception,otherwise you can track via Null Pointer exception.
public void updateJSONData() {
JSONObject json = jParser.getJSONFromUrl(my_url);
try {
int success = json.getInt("success");
boolean isAvail=json.has("users");
if (success == 1) {
if(isAvail)
JSONArray users = json.getJSONArray("users");
for (int i = 0; i<users.length(); i++) {
}
}
}
catch(Exception e){
}
}

1. jParser is NULL so use
// make sure my_url has json string in it
// read json first and use in place of my_url
JSONObject jsonObjTokener = (JSONObject) new JSONTokener(my_url).nextValue();
// get success
String isSuccess = jsonObjTokener.getString("success");
// get users
JSONObject mUser = jsonObjTokener.getJSONObject("users");
at that line
2. You did spelling mistake at
String name = c.getString("NAAM");
correct to
String name = c.getString("NAME");

Android AsyncTask: How to handle the return type

I am working on an Android application that executes an http POST request, and the tutorial I followed was resulting in an android.os.NetworkOnMainThreadException
The original code was something like this.
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
public JSONObject getJSONFromUrl(String url, List<NameValuePair> params) {
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
Log.e("JSON", json);
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}
And this class was invoked with this line.
JSONObject json = jsonParser.getJSONFromUrl(loginURL, params);
After changing this to an AsyncTask class, the code looks like this.
class JSONParser extends AsyncTask<String, Void, JSONObject>{
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// variables passed in:
String url;
List<NameValuePair> params;
// constructor
public JSONParser(String url, List<NameValuePair> params) {
this.url = url;
this.params = params;
}
#Override
protected JSONObject doInBackground(String... args) {
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
Log.e("JSON", json);
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
#Override
protected void onPostExecute(JSONObject jObj) {
return;
}
}
My question is, how do I return a JSONObject from this new AsyncTask class?I can see that jObj is being returned in doInBackground(), but I am not sure where it is being returned to.
What do I need to modify or how do I need to call my new JSONParser class so that it is returning a JSONObject?

Have a look at this code, it may give you an insight as to how to deal with the parsing of JSON objects. I am just posting the onPostExecute function for now because you seemed to have all the rest figured correctly.
As for your doubt as to where the data object from the doInBackground is returned, it is automatically sent to the onPostExecute where you can further on parse it.
#Override
protected void onPostExecute(JSONObject result)
{
try
{
JSONObject data = result.getJSONObject("data");
// whatever your JSON tag may be, in this case its data.
if (data.isNull("data"))
{
// action to handle null JSON object.
}
else
{
JSONArray jarray = data.getJSONArray("data");
int len=jarray.length();
for (int i = 0; i < jarray.length(); i++)
{
JSONObject obj = (JSONObject) jarray.get(i);
String instanceName = obj.getString("instanceName");
//extract data by whatever tag names you require, in this case instanceName.
}
}
}
catch (JSONException je)
{
je.printStackTrace();
Log.d(TAG, "Error: " + je.getMessage());
}
}
}

from your doInBackground Method
#Override
protected JSONObject doInBackground(String... args) {
return jObj;
}
your return your JsonObject to
#Override
protected void onPostExecute(JSONObject jObj) {
// Here you get your return JsonObject
}

An Async Task has 3 attribures
Params, the type of the parameters sent to the task upon execution.
Progress, the type of the progress units published during the background computation.
Result, the type of the result of the background computation.
The point you need to understand is that you are creating a object of Async Task Class While calling new JSONParser(loginURL, params);
The solution is that create a public result variable in your Async class and the call execute() on the object of class and then access the public object from the object.

I can see that jObj is being returned in doInBackground() but I am not
sure where it is being returned to.
The result of doinBackground() is received as a parameter in onPostExecute(). You are returning a json object in doinBackground() which is a parameter to onPostExecute().
#Override
protected void onPostExecute(JSONObject jObj) {
return;
}
Usage
new JSONParser().execute("url);
class JSONParser extends AsyncTask<String, Void, JSONObject>{
//string parameter to doInBackground()
//JSONObject - result returned in doInBackground() received as a param in onPostExecute()
}
You can also pass paramters to the constructor of your asynctask
new JSONParser("url",params).execute();
In your asynctask;
String url;
List<NameValuePair> params;
// constructor
public JSONParser(String url, List<NameValuePair> params) {
this.url = url;
this.params = params;
}

httpPost not working using asynctask - giving invalid index, size is 0 exception

In order to avoid executing the http relating things in the UI thread, i migrated my code inside asynctask, before that, it was working fine on versions before 3.0 -- however, after literally copy pasting the code inside asynctask, it started to giving the invalid index, size is 0 exception. Whenever I need to use the method I am applying the call --
new dataRetrievalViaAsyncTask().execute(url, null, null); --
Whats wrong down there ?
class dataRetrievalViaAsyncTask extends AsyncTask<String, Void, Void>
{
#Override
protected void onPreExecute()
{
super.onPreExecute();
}
#Override
protected Void doInBackground(String... f_url)
{
Log.i("tag", "inside doInBackground");
String url2 = f_url[0];
Log.i("tag", url2);
HttpClient httpclient = new DefaultHttpClient();
Log.i("tag", "done : HttpClient httpclient = new DefaultHttpClient();");
HttpPost httppost = new HttpPost(url2);
Log.i("tag", "done : HttpPost httppost = new HttpPost(url);");
try
{
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
Log.i("tag", "done : httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));");
HttpResponse response = httpclient.execute(httppost);
Log.i("tag", "done : HttpResponse response = httpclient.execute(httppost);");
HttpEntity entity = response.getEntity();
Log.i("tag", "done : HttpEntity entity = response.getEntity();");
is = entity.getContent();
Log.i("tag", "after : is = entity.getContent();");
} catch (Exception e)
{
Log.e("log_tag", "Error in http connection", e);
}
// convert response to string
return null;
}
protected void onPostExecute()
{
try
{
Log.i("tag","before : BufferedReader reader = new BufferedReader(new Inp");
BufferedReader reader = new BufferedReader(new InputStreamReader(is, "iso-8859-1"), 8);
sb = new StringBuilder();
sb.append(reader.readLine() + "\n");
String line = "0";
while ((line = reader.readLine()) != null)
{
sb.append(line + "\n");
}
is.close();
result = sb.toString();
} catch (Exception e)
{
Log.e("log_tag", "Error in http connection", e);
}
try
{
Log.i("tag", "before : jsons ");
jArray = new JSONArray(result);
JSONObject json_data = null;
Log.i("tag", Integer.toString(jArray.length()));
for (int i = 0; i < jArray.length(); i++)
{
json_data = jArray.getJSONObject(i);
uid = json_data.getInt("uid");
item1= json_data.getString("item1");
item2 = json_data.getString("item2");
item3 = json_data.getString("item3");
item4 = json_data.getString("item4");
item5 = json_data.getString("item5");
item6 = json_data.getString("item6");
favorited = json_data.getString("favorited");
currentList.add(new itemClass(uid, item1 item2)); //there is a constructor for this in the itemClass
itemClass toSendToOffline = new itemsClass(uid, item1, item2, item3, item4, item5, item6, favorited);
myDBHelper.insertFromOnlineToDBtoSendToOffline();
}
} catch (JSONException e1)
{
Toast.makeText(getBaseContext(), "Not Found", Toast.LENGTH_LONG).show();
} catch (ParseException e1)
{
e1.printStackTrace();
}
super.onPostExecute(null);
}
}
(mainly the code is stopping at --
HttpResponse response = httpclient.execute(httppost);

I can not see nameValuePairs variable initialized anywhere, which is actually causing problem.

class dataRetrievalViaAsyncTask extends AsyncTask<Void, Void, String>
{
String URL = "";
public dataRetrievalViaAsyncTask( String url )
{
URL = url;
}
#Override
protected void onPreExecute()
{
}
#Override
protected String doInBackground(Void... f_url)
{
String result="";
try
{
result=fetchdataFromServer(URL);
}
catch (JSONException e)
{
e.printStackTrace();
}
return result;
}
protected void onPostExecute(String result)
{
// See your results as string //result
}
public JSONObject getJsonObjectToRequestToServer(String plid) throws JSONException
{
JSONObject parms = new JSONObject();
parms.put("user_id", "");
parms.put("app_key", "xyz");
parms.put("secret", "abc");
parms.put("token", "");
parms.put("playurl", "1");
parms.put("mode", "playlistdetail");
parms.put("playlist_id", plid);
return parms;
}
public String fetchdataFromServer(String url) throws JSONException
{
String stringresponce = null;
try
{
HttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(URL);
JSONObject parms = getJsonObjectToRequestToServer("1");
StringEntity se;
se = new StringEntity(parms.toString());
httpPost.setEntity(se);
httpPost.setHeader("Content-type", "application/json");
#SuppressWarnings("rawtypes")
ResponseHandler responseHandler = new BasicResponseHandler();
stringresponce = httpClient.execute(httpPost, responseHandler);
}
catch (UnsupportedEncodingException e)
{
e.printStackTrace();
}
catch (ClientProtocolException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
return stringresponce;
}
}
put this code in your code and pass arguments ass you need this is the way how i request to server and get json response as string from result variable pass arguments to your url as i passed by making json object then convert them to string
then execute like this............
dataRetrievalViaAsyncTask asyncTask=new dataRetrievalViaAsyncTask(Yoururl);
asyncTask.execute();
hope this will help if you have some issues please post here thanks......