Develop Reference

Simplest straight forward way to get a JSON String from a REST URL

I am trying to get a JSON string from a url and save it into SQLite in my android app.
I was trying some tutorials then realize the suggested methods has a void return type. Are there a more simple straight forward way of getting a JSON String and putting it into an arraylist ready to be saved into SQLite?
Below is what I was stuck at a helper class that gets the data from the url
as they said that the main thread OnCreate does not allow a background process like this. Is there a way to change the return type of AsyncTask or is there a more simple way to fetch JSON String with android?
public class FetchData extends AsyncTask<Void, Void, Void> {
#Override
protected void doInBackground(ArrayList<String>... voids) {
try {
URL url = new URL("http://192.168.403.211/api/wordsupdate.php");
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
InputStream inputStream = httpURLConnection.getInputStream();
BufferedReader bufferedReader = new BufferedReader (new InputStreamReader(inputStream));
String line ="";
while (line != null) {
line = bufferedReader.readLine();
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}

Go with Volley API. Check the code below which demonstrate POST request. Hope you'll get useful information.
public void getAddress(final String uid) {
String url = "Add Url Here"; // Request a string response from the provided URL.
StringRequest stringRequest = new StringRequest(Request.Method.POST, url,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
JSONArray dataArray;
JSONObject jsonObject;
address_ids = new ArrayList<>();
address_names = new ArrayList<>();
address_line1 = new ArrayList<>();
address_line2 = new ArrayList<>();
address_state = new ArrayList<>();
address_district = new ArrayList<>();
address_taluka = new ArrayList<>();
address_pincode = new ArrayList<>();
address_status = new ArrayList<>();
address_default = new ArrayList<>();
try {
jsonObject = new JSONObject(response);
dataArray = jsonObject.getJSONArray(JSON_ARRAY);
//adding response values to respective array
for (int i = 0; i < dataArray.length(); i++) {
//Creating a json object of the current index
JSONObject obj;
try {
//getting json object from current index
obj = dataArray.getJSONObject(i);
address_ids.add(obj.getString(TAG_ADDRESS_ID));
address_names.add(obj.getString(TAG_ADDRESS_NAME));
address_line1.add(obj.getString(TAG_ADDRESSLINE_FIRST));
address_line2.add(obj.getString(TAG_ADDRESSLINE_SECOND));
address_state.add(obj.getString(TAG_STATE));
address_district.add(obj.getString(TAG_DISTRICT));
address_taluka.add(obj.getString(TAG_TALUKA));
address_pincode.add(obj.getString(TAG_PINCODE));
address_status.add(obj.getString(TAG_ADDRESS_STATUS));
} catch (JSONException e) {
e.printStackTrace();
}
}
} catch (JSONException e) {
e.printStackTrace();
}
//setting up response values to the fragment
//Toast.makeText(getActivity(), "Error:"+response, Toast.LENGTH_LONG).show();
Log.e(TAG, "onResponse: " + response);
address_name.setText("Name : " + address_names.get(0));
address.setText("Address : " + address_line1.get(0) + "," + address_line2.get(0) + "-" + address_pincode.get(0));
taluka.setText("Taluka : " + address_taluka.get(0));
district.setText("District : " + address_district.get(0));
state.setText("State : " + address_state.get(0));
mCircularProgressBar.setIndeterminate(false);
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getApplication(), "Taking bit longer", Toast.LENGTH_LONG).show();
}
}) {
#Override
protected Map<String, String> getParams() {
Map<String, String> params = new HashMap<String, String>();
params.put("mk_address_id", address_id);
return params;
}
};
queue.add(stringRequest);
}

Check this link from Android developer, you can find more info their.
In your code change the "extends" from
AsyncTask<Void, Void, Void>
to
AsyncTask<Void, Void, String>
and the doInBackground method to
protected String doInBackground(ArrayList<String>... voids)
and you will get the string back in the onPostExecute method

Yes there is a way to change the return types: Have a look at your extends AsyncTask: It says AsyncTask<Void, Void, Void>.
According to Android Developers, this means <Params, Progress, Result>.
This means that your
ArrayList<String>... voids won't work too, because you have the Params part set to Void but try to get an ArrayList<String>.
So, to solve your problem, change the three Voids to whatever you need it to input and output.
However, to deserialize JSON you should use an external library (or use a 3rd party library for REST calls altogether).

//AsyncTask has onPostExecute which will be called after background execution, where you will get the result in mainthread
class FetchData extends AsyncTask<Void, Void, String> {
#Override
protected String doInBackground(Void... voids) {
try {
URL url = new URL("http://192.168.403.211/api/wordsupdate.php");
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
InputStream inputStream = httpURLConnection.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
StringBuilder builder = new StringBuilder();
String line;
while ((line = bufferedReader.readLine()) != null) {
builder.append(line);
}
return builder.toString();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String result) {
//Your result String is here which runs on MAIN THREAD
super.onPostExecute(result);
}
}

Retrofit 2 will help you - easy and simple
Edit : For Async task see the top answer here
What arguments are passed into AsyncTask<arg1, arg2, arg3>?

In your code snippet , you specified AsyncTask params types are Void. Void means , it does't have any return value. As per AsyncTask Syntax,
You have to specify three arguments.
1- InputType- DoInBanckground
2- ProgressType - Publish Progress.
3- OutputType - OnPostExecute.
The three types used by an asynchronous task are the following:
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.
In your snippet doInBackground method and AsycTask types are mismatching .
For more information : https://developer.android.com/reference/android/os/AsyncTask.html

Retrieve data from Google Books API

I'm new to Android and using web APIs, and I'm writing an Android App that scans a barcode from a book and then search its ISBN in Google Books API.
I have this url after the barcode scan: https://www.googleapis.com/books/v1/volumes?q=isbn:9788432250651&AIzaSyCpYez5556X4UzPV6rF4kkspj9DsCs_Q_c
And the next code:
private class GetBookInfo extends AsyncTask <View, Void, Integer> {
#Override
protected Integer doInBackground(View... urls) {
// make Call to the url
makeCall("https://www.googleapis.com/books/v1/volumes?" +
"q=isbn:" + ean_content + "&AIzaSyCpYez5556X4UzPV6rF4kkspj9DsCs_Q_c");
//print the call in the console
System.out.println("https://www.googleapis.com/books/v1/volumes?" +
"q=isbn:" + ean_content + "&AIzaSyCpYez5556X4UzPV6rF4kkspj9DsCs_Q_c");
return null;
}
#Override
protected void onPreExecute() {
// we can start a progress bar here
}
#Override
protected void onPostExecute(Integer result) {
String ruta = save_cover(getApplicationContext(), title, book_cover);
Intent intent = new Intent(MainActivity.this, Spreadsheets.class);
// intent.putExtra(title,title);
// intent.putExtra(author,authors);
// intent.putExtra(date,date);
// intent.putExtra(category,categories);
// intent.putExtra(description,description);
//finish();
startActivity(intent);
finish();
}
}
public void makeCall(String stringURL) {
URL url = null;
BufferedInputStream is = null;
JsonReader jsonReader;
try {
url = new URL(stringURL);
} catch (Exception ex) {
System.out.println("Malformed URL");
}
try {
if (url != null) {
HttpsURLConnection urlConnection = (HttpsURLConnection) url.openConnection();
is = new BufferedInputStream(urlConnection.getInputStream());
}
} catch (IOException ioe) {
System.out.println("IOException");
}
if (is != null) {
try {
jsonReader = new JsonReader(new InputStreamReader(is, "UTF-8"));
jsonReader.beginObject();
while (jsonReader.hasNext()) {
String name = jsonReader.nextName();
if (name.equals("title")) {
title = jsonReader.nextString();
}
else if (name.equals("authors")) {
authors = jsonReader.nextString();
}
else if (name.equals("publishedDate")) {
date = jsonReader.nextString();
}
else if (name.equals("categories")) {
categories = jsonReader.nextString();
}
else if (name.equals("description")) {
description = jsonReader.nextString();
}
// else if (name.equals("averageRating")) {
// rating = jsonReader.nextString();
// }
else if (name.equals("thumbnail")) {
image = jsonReader.nextString();
book_cover = download_cover(image);
}
else {
jsonReader.skipValue();
}
}
jsonReader.endObject();
}
catch (Exception e) {
System.out.println("Exception");
}
}
}
This isn't retrieving anything from the API. I would appreciate your help, thank you!

I think what you need to do next is request a connection from the API, open the connection, using JSON retrieve data from the API and use the inputStream to get the data stored in an array.
something like :Implement these methods in a class:
private static String makeHttpRequest(URL url) throws IOException
private static String readFromStream(InputStream inputStream) throws IOException
private static List extractFeatureFromJson(String booksJson)
public static List featchBookData(String requestUrl)

Here is a full code example of how to use Google Books API in Android with Feign or Retrofit. These libraries provide a higher level abstraction on top of HTTP so that you can use simple method calls and objects in your code, instead of messing with requests, responses and JSON deserialization.

"Standard simple" interfaces in Java?

So here in Java I've written a typical class, to send json to a rest server. (I'll include the whole class below for clarity.) So that's a file "Fetcher.java"
Now for the callback you need an interface. The interface is trivial, just one function with a string.
public interface FetcherInterface {
public void fetcherDone(String result);
}
Annoyingly you need a whole file for that, "FetcherInterface.java"
So this interface is nothing but "one callback with a string". Often all you need is just "one callback with no arguments".
In fact ........ are there some sort of standard interfaces I can use, or something like that?
It seems kind of annoying to have to put in a whole interface for such a simple "standard" interface.
What's the deal on this? What's the javaly solution?
It seems you CAN NOT put it in the same file:
Perhaps I misunderstand something there. If you could put it in the same file, that would be convenient at least.
(Lambdas are not yet practically available. Anyway, sometimes you want an interface.)
Just for clarity, here's how you call the class
JSONObject j = new JSONObject();
try {
j.put("height", 2.1);
j.put("width", 2.5);
j.put("command", "blah");
} catch (JSONException e) {
e.printStackTrace();
}
new Fetcher("mobile/login", j, new FetcherInterface() {
#Override
public void fetcherDone(String result) {
Log.d("DEV","all done");
doSomething(result);
}
}
).execute();
or indeed
public class HappyClass extends Activity implements FetcherInterface {
...
private void someCall() {
JSONObject j = new JSONObject();
try {
j.put("height", 2.1);
j.put("width", 2.5);
j.put("command", "blah");
} catch (JSONException e) {
e.printStackTrace();
}
new Fetcher("mobile/data", j, this).execute();
devBlank();
}
#Override
public void fetcherDone(String result) {
Log.d("DEV","all done" +result);
doSomething(result);
}
Here's the whole class... Fetcher.java file
public class Fetcher extends AsyncTask<Void, Void, String> {
private String urlTail;
private JSONObject jsonToSend;
private FetcherInterface callback;
// initializer...
Fetcher(String ut, JSONObject toSend, FetcherInterface cb) {
urlTail = ut;
jsonToSend = toSend;
callback = cb;
}
#Override
protected String doInBackground(Void... params) {
HttpURLConnection urlConnection = null; // declare outside try, to close in finally
BufferedReader reader = null; // declare outside try, to close in finally
String rawJsonResultString = null;
String json = jsonToSend.toString();
Log.d("DEV","the json string in Fetcher is " +json);
try {
URL url = new URL("https://falcon.totalfsm.com/" + urlTail);
Log.d("DEV","the full URL in Fetcher is " +url);
// open a json-in-the-body type of connection.......
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("POST");
urlConnection.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
urlConnection.setDoOutput(true);
urlConnection.setDoInput(true);
urlConnection.setConnectTimeout(5000);
// urlConnection.setDoOutput(false); // can be important?
urlConnection.connect();
OutputStream os = urlConnection.getOutputStream();
os.write(json.getBytes("UTF-8"));
os.close();
// annoyingly, you have to choose normal versus error stream...
InputStream inputStream;
int status = urlConnection.getResponseCode();
if (status != HttpURLConnection.HTTP_OK)
inputStream = urlConnection.getErrorStream();
else
inputStream = urlConnection.getInputStream();
if (inputStream == null) { // nothing to do.
return null;
}
StringBuffer buffer = new StringBuffer();
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) { // adding newlines makes debugging easier
buffer.append(line + "\n");
}
if (buffer.length() == 0) { // stream was empty
return null;
}
rawJsonResultString = buffer.toString();
return rawJsonResultString;
} catch (IOException e) {
Log.e("PlaceholderFragment", "Error ", e);
return null;
} finally{
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e("PlaceholderFragment", "Error closing stream", e);
}
}
}
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
Log.d("DEV", "Fetcher done");
if (s==null) {
Log.d("DEV","applying anti-null measures in Fetcher!");
s = "message from app communications layer: 'null' returned from servers for that call at " +urlTail;
}
callback.fetcherDone(s);
}
}

I feel bad answering my own question, but as there were no other answers this info may be helpful.
DaveNewton and Rowtang have supplied the exact answers here:
(Point 1) If you want a genuinely public interface, it goes in its own file. That's how Java works. There's no alternative.
(Point 2) Normally, use protected interface and declare the interface inside the class. It can then be used throughout the app.
So...
public class Fetcher extends AsyncTask<Void, Void, String> {
protected interface FetcherInterface {
public void fetcherDone(String result);
}
private String urlTail;
private JSONObject jsonToSend;
private FetcherInterface callback;
Fetcher(String ut, JSONObject toSend, FetcherInterface cb) {
urlTail = ut;
jsonToSend = toSend;
callback = cb;
}
#Override
protected String doInBackground(Void... params) {
....
(c# programmers would maybe call it "IFetcher".)

JSoup parsed elements empty

I am trying to parse some data using JSoup, this is all happening in a asynctask (doInBackground) part of my MainActivity.
Unfortunately all the elements (9) are empty when I execute the app.
When I debug below codeline, I actually get the complete website, it`s all there.
The method readMultipleLinesRespone() is located in another class HttpUtility where I also call my Post and Get requests.
I tested this upfront by saving the website as a file and using JSoups assets ability, it worked perfectly then.
The setupAdapter() method in onPostExecute fills a ExpandableListview with data, should this info be nessecary. If you need more info pls ask.
Can somebody assist and tell me what I am doing wrong?
response1 = util.readMultipleLinesRespone(); <--- debugged and all data (seems) to be there but isn`t.
Edit: If I print response1, there is indeed no data to parse.
Logcat output:
E/Resonse:: [Ljava.lang.String;#3d3410a
Below is the method readMultipleLinesRespone from HttpUtility class:
public String[] readMultipleLinesRespone() throws IOException {
InputStream inputStream = null;
if (httpConn != null) {
inputStream = httpConn.getInputStream();
} else {
throw new IOException("Connection is not established.");
}
BufferedReader reader = new BufferedReader(new InputStreamReader(
inputStream));
List<String> response = new ArrayList<String>();
String line = "";
while ((line = reader.readLine()) != null) {
response.add(line);
}
reader.close();
return (String[]) response.toArray(new String[0]);
}
The asynctask where it`s all hapening:
private class FetchWebsiteData extends AsyncTask<Void, Void, Void> {
ProgressDialog mProgressDialog;
#Override
protected void onPreExecute() {
this.mProgressDialog = new ProgressDialog(getActivity());
mProgressDialog.setMessage("Laden...");
mProgressDialog.setIndeterminate(false);
mProgressDialog.show();
}
#Override
protected Void doInBackground(Void... result) {
try {
util.sendGetRequest("https://mobile.somesite.nl/Data", null);
response1 = util.readMultipleLinesRespone();
} catch (IOException e) {
e.printStackTrace();
}
if (response1.length > 0) {
Document doc = Jsoup.parse(response1.toString());
// Get the html document title
Elements els = doc.select("span[class=item-value pull-right]");
if (els.size() > 0) {
fac_naam = els.get(0).text();
fac_straat = els.get(1).text();
fac_post = els.get(2).text();
con_tel = els.get(3).text();
con_email = els.get(4).text();
betaal_reknr = els.get(5).text();
betaal_houd = els.get(6).text();
zig_gebruiker = els.get(7).text();
zig_wacht = els.get(8).text();
}
}
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPreExecute();
setupAdapter();
mProgressDialog.dismiss();
}
}

In the meantime I solved the problem.
I did not pass the response string correctly to the asynctask which parses the required elements.
Just required a public string in which the response is being set and passed (not an elegant way but it works):
public static String HttpResponse = "";
In the HttpUtility class:
public String[] readMultipleLinesRespone() throws IOException {
...
TabFragment1.HttpResponse = response.toString();
...
return (String[]) response.toArray(new String[0]);
}
Then pass it to the asynctask:
#Override
protected Void doInBackground(Void... result) {
try {
util.sendGetRequest(LoginActivity.PersData_URL, null);
util.readMultipleLinesRespone();
} catch (IOException e) {
e.printStackTrace();
}
if (HttpResponse.length() > 0) {
Document doc = Jsoup.parse(HttpResponse.toString());
// Get the html document title
Elements els = doc.select("span[class=item-value pull-right]");
...
}
return null;
}

Can I use AsyncTask inside ListFragment? or should I use AsyncTaskLoader?

I tried the code below and also tried the AsyncTaskLoader approach. The app crashes when I instantiate the AsyncTask. Pleas advise me on the best approach to load JSON in a list fragment inside tab host.
The code below is the tab fragment (I use action bar tabs in main activity):
public class TabTop extends ListFragment {
Context context = getActivity().getBaseContext();
String API_URL = "http://api.rottentomatoes.com/api/public/v1.0/movies/770672122/similar.json?apikey=crhhxb4accwwa6cy6fxrm8vj&limit=1";
ArrayList<Deal> deals;
DealsListAdapter adapter;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
#SuppressWarnings("unused")
int a = 0;
return super.onCreateView(inflater, container, savedInstanceState);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
GetTopDeals getTopDeals = new GetTopDeals(context);
getTopDeals.execute(API_URL);
super.onActivityCreated(savedInstanceState);
}
class GetTopDeals extends AsyncTask<String, Void, ArrayList<Deal>>{
ProgressDialog progressDialog;
public GetTopDeals(Context activity) {
this.progressDialog = new ProgressDialog(activity);
}
#Override
protected void onPostExecute(ArrayList<Deal> result) {
adapter = new DealsListAdapter(context, result);
setListAdapter(adapter);
super.onPostExecute(result);
}
#Override
protected void onPreExecute() {
progressDialog.setCancelable(true);
progressDialog.setProgress(0);
progressDialog.setMessage("loading Top deals...");
progressDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
super.onPreExecute();
}
#Override
protected ArrayList<Deal> doInBackground(String... urls) {
String response = sendRequest(urls[0]); // make request for json
return processResponse(response); // parse the Json and return ArrayList to postExecute
}
private String sendRequest(String apiUrl) {
BufferedReader input = null; // get the json
HttpURLConnection httpCon = null; // the http connection object
StringBuilder response = new StringBuilder(); // hold all the data from the jason in string separated with "\n"
try {
URL url = new URL(apiUrl);
httpCon = (HttpURLConnection) url.openConnection();
if (httpCon.getResponseCode() != HttpURLConnection.HTTP_OK) { // check for connectivity with server
return null;
}
input = new BufferedReader(new InputStreamReader(httpCon.getInputStream())); // pull all the json from the site
String line;
while ((line = input.readLine()) != null) {
response.append(line + "\n");
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (input != null) {
try {
input.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (httpCon != null) {
httpCon.disconnect();
}
}
return response.toString();
}
}
public ArrayList<Deal> processResponse(String response) {
try {
JSONObject responseObject = new JSONObject(response); // Creates a new JSONObject with name/value mappings from the JSON string.
JSONArray results = responseObject.getJSONArray("movies"); // Returns the value mapped by name if it exists and is a JSONArray.
deals = new ArrayList<Deal>();
for (int i = 0; i < results.length(); i++) { // in this loop i copy the json array to movies arraylist in order to display listView
JSONObject jMovie = results.getJSONObject(i);
int api_id = jMovie.getInt("id");
String name = jMovie.getString("title");
String content = jMovie.getString("synopsis");
JSONObject posters = jMovie.getJSONObject("posters");
String image_url = posters.getString("profile");
}
}catch (JSONException e) {
e.printStackTrace();
}
return deals;
}
#Override
public void onStart() {
super.onStart();
}
#Override
public void onListItemClick(ListView l, View v, int position, long id) {
Intent intent = new Intent(getActivity().getBaseContext(), DealInformation.class);
startActivity(intent);
super.onListItemClick(l, v, position, id);
}
}

Make your asynctask in his own file.
And when your asynctask is finish, implement OnPostExecute which is automatically call. Notify your adapter by a notifyDataSetChanged like that :
#Override
protected void onPostExecute(List<NewItem> list) {
Adapter.getListe().clear();
Adapter.getListe().addAll(list);
Adapter.notifyDataSetChanged();
}

thank you guys,
i want to post my answer. after some research i decided to go with AsyncTaskLoader.
this is my code
public class TabOurPicks extends ListFragment implements LoaderCallbacks<String[]> {
// when activity loads- onActivityCreated() calls the initLoader() who activate onCreateLoader()
#Override
public void onActivityCreated(Bundle savedInstance) {
super.onActivityCreated(savedInstance);
setListAdapter(new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, new String[]{}));
getLoaderManager().initLoader(0, null,this).forceLoad();
}
// onCreateLoader instantiate the asynctaskloaser who work in bg
#Override
public RSSLoader onCreateLoader(int arg0, Bundle arg1) {
return new RSSLoader(getActivity()); //
}
// after bg process invoke onLoadFinished() who work in ui thread
#Override
public void onLoadFinished(Loader<String[]> loader, String[] data) {
setListAdapter(new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, data
) );
}
#Override
public void onLoaderReset(Loader<String[]> arg0) {
// TODO Auto-generated method stub
}
and this is the inner class for the loader:
static public class RSSLoader extends AsyncTaskLoader<String[]>
{
public RSSLoader(Context context) {
super(context);
}
#Override
public String[] loadInBackground() {
String url = "http://api.rottentomatoes.com/api/public/v1.0/movies/770672122/similar.json?apikey=crhhxb4accwwa6cy6fxrm8vj&limit=1";
String response = sendRequest(url);
return processResponse(response);
}
private String sendRequest(String url) {
BufferedReader input = null; // get the json
HttpURLConnection httpCon = null; // the http connection object
StringBuilder response = new StringBuilder(); // hold all the data from the jason in string separated with "\n"
try {
URL apiUrl = new URL(url);
httpCon = (HttpURLConnection) apiUrl.openConnection();
if (httpCon.getResponseCode() != HttpURLConnection.HTTP_OK) { // check for connectivity with server
return null;
}
input = new BufferedReader(new InputStreamReader(httpCon.getInputStream())); // pull all the json from the site
String line;
while ((line = input.readLine()) != null) {
response.append(line + "\n");
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (input != null) {
try {
input.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (httpCon != null) {
httpCon.disconnect();
}
}
return response.toString();
}
private String[] processResponse(String response) {
String[] deals = null;
try {
JSONObject responseObject = new JSONObject(response); // Creates a new JSONObject with name/value mappings from the JSON string.
JSONArray results = responseObject.getJSONArray("movies"); // Returns the value mapped by name if it exists and is a JSONArray.
deals = new String[10];
for (int i = 0; i < 9; i++) { // in this loop i copy the json array to movies arraylist in order to display listView
JSONObject jMovie = results.getJSONObject(i);
String name = jMovie.getString("title");
deals[i] = name;
}
}catch (JSONException e) {
e.printStackTrace();
}
return deals;
}
}
}

It doesn't matter if your asynctask has its own file. You just don't want your activity to extends asynctask as this would make your activity asynchronous - but this is impossible to do anyways due to java's double inheritance rule.
Based on the architecture of your app and your programming style the asyntask can be an inner class in the activity. on the PostExecute method make sure you have given data to your adapter and that the adapter is set to the list, then just run notifyDataSetChanged().
Assuming your asynctask is loading data from cache or the network you are on the right track with your approach to this.