Develop Reference

How to cancel the async task with tab host

I am currently working with the tab host and fragment. Currently I set fragment a to download json A and fragment B to download json B , the problem is when I switch fragment, the fragment A onPostExecute function will fall into the fragment B one , is there any way to fix this?
Thanks
Tab host:
tabHost = (FragmentTabHost) findViewById(R.id.tabhost);
tabHost.setup(this, getSupportFragmentManager(), R.id.tabcontent);
tabHost.addTab(
tabHost.newTabSpec("Home").setIndicator("",
res.getDrawable(R.drawable.btn_about)), Home.class,
null);
tabHost.addTab(
tabHost.newTabSpec("About").setIndicator("",
res.getDrawable(R.drawable.btn_about)), About.class,
null);
The async task
public class JSONReader {
public static final String TAG = "JSONReader";
public ArrayList<Record> records;
public Record myRecordObj;
public ArrayList<GalleryImage> images;
public String url;
public int failCount = 0; // retry twice
public Context ctx;
public String readCase;
public JSONReader(String _url, Context _ctx , String _readCase) {
url = _url;
ctx = _ctx;
readCase = _readCase;
}
public void getJSON() {
new JSONDownload().execute(url);
}
private class JSONDownload extends AsyncTask<String, Void, JSONObject> {
// TODO Auto-generated method stub
StringBuilder builder = new StringBuilder();
String temp = "";
String json = ""; // json content
InputStream input = null;
OutputStream output = null;
HttpURLConnection connection = null;
#Override
protected JSONObject doInBackground(String... params) {
// TODO Auto-generated method stub
try {
Log.d(TAG, "Start reading: " + url);
URL url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK)
return null;
// return "Server returned HTTP " + connection.getResponseCode()
// + " " + connection.getResponseMessage();
input = connection.getInputStream();
BufferedReader reader = new BufferedReader(
new InputStreamReader(input));
while ((temp = reader.readLine()) != null) {
builder.append(temp);
}
json = builder.toString();
} catch (Exception e) {
return null;
} finally {
try {
if (input != null)
input.close();
if (output != null)
output.close();
} catch (IOException ignored) {
}
if (connection != null)
connection.disconnect();
}
try {
return new JSONObject(json);
} catch (JSONException e) {
e.printStackTrace();
return null;
}
}
#Override
protected void onPostExecute(JSONObject result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
onJSONDownloaded(result);
}
}
public void onJSONDownloaded(JSONObject result) {
// TODO Auto-generated method stub
if (result != null) {
failCount = 0;
if (readCase.equals("leaderBoard")){
records = new ArrayList<Record>();
try {
JSONObject myRecord = result.getJSONObject("myRecord");
if (myRecord != null) {
myRecordObj = new Record(myRecord.getString("pic"),myRecord.getString("name"),myRecord.getString("score"));
}
JSONArray topRecords = result.getJSONArray("topRecord");
for (int i = 0; i < topRecords.length(); i++) {
JSONObject topRecord = topRecords.getJSONObject(i);
String topName = topRecord.getString("name");
String topPic = topRecord.getString("pic");
String topScore = topRecord.getString("score");
records.add(new Record(topPic, topName, topScore));
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
((LeaderBoardDetail)ctx).setData(records,myRecordObj);
} else if (readCase.equals("galleryList")){
images = new ArrayList<GalleryImage>();
try {
JSONArray imageList = result.getJSONArray("images");
for (int i = 0; i < imageList.length(); i++) {
JSONObject image = imageList.getJSONObject(i);
images.add(new GalleryImage(image.getString("url"),image.getString("thumbUrl"),image.getString("category"),image.getString("userPic"),image.getString("name")));
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//exception
if (((FragmentActivity) ctx).getSupportFragmentManager().findFragmentById(R.id.tabcontent).getTag().equals("Gallery")) {
PhotoGallery galleryFragment = (PhotoGallery) ((FragmentActivity) ctx).getSupportFragmentManager().findFragmentById(R.id.tabcontent);
galleryFragment.setData(images);
}
}
} else {
if (failCount <= 1) { // check global_conf twice if fail
failCount++;
Log.d(TAG, "No of retry" + failCount);
new JSONDownload().execute(url); // Retry download json
} else {
failCount = 0;
}
}
}
}

I used it in my app this way which works for me and answer is a bit similar to another answer but few additions and more detail. Hope it help you too.
NOTE: This is just a idea, u need to try, it may vary as per your app architect.
At your activity make the task object global [make sure set task obj null once task is finish]
JSDownload js = null;
public void getJSON() {
if(js != null && js.getStatus() == AsyncTask.Status.RUNNING)
{
js.cancel(true);
if(js.isCancelled())
{
js = new JSONDownload();
js.execute(url);
}
else
{
js = new JSONDownload();
js.execute(url);
}
}
At the Async class side....[make sure u take care null result # onpostExcute]
class JSONDownload extends AsyncTask<String, Void, JSONObject>
{
protected JSONObject doInBackground(String... params) {
// TODO Auto-generated method stub
try {
if(!this.isCancelled())
{
//make http connection ..
URL url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
//as we are in steps in bg check iscancel .. again
//if its a loop here we call break; and return null once only..
if(this.isCancelled())
return null;
// connection status check and get buffer etc .. code here
if(this.isCancelled())
return null;
//read data
return data;
}
} catch (Exception e) {
return null;
}
}
#Override
protected void onCancelled(){
// If you write your own implementation, do not call super.onCancelled(result).
}
}

Use the global async task variable
LongOperation LongOperationOdeme = new LongOperation();
and set:
LongOperationOdeme.cancel(true);
This will stop any async task running at that moment, it's what the back button does

If you are not looking for a simplest answer but for a maybe more interesting and elegant, have a peek at this article, especially if you find functional programming interesting.
It's easier than it looks, i was almost unfamiliar to FP before this article but it covers common problems related to AsyncTask and asynchronicity in Android in general, so I got the gist and consider to use Observables instead of AsyncTask in the future projects myself. It is RxJava and it can solve your problem gracefully: "The fromFragment call transforms the given source observable in such a way that events will only be emitted to the fragment if it’s still alive and attached to its host activity."
One more citation form the article: "What if the user decides to back out of the Activity that triggered the task, and we are holding on to a stale reference. This not only creates a substantial memory leak, but is also worthless because meanwhile it has been detached from the application window. A problem that everyone is well aware of."

App with json and sqlite crashes if internet connection is not available

I am working on JSON data fetching and displaying but before that I store it in Sqlite.
After fetching from that Sqlite table, it works fine when internet is available but app automatically closed when internet connection is not available. I am using hash-map custom adapter to showing data in listview. I have created a fetchdata method from SqlHelper class
protected Void doInBackground(Void... params)
{
// Create an array
arraylist = new ArrayList<HashMap<String, String>>();
int state = NetworkUtilClass.checkInternetConenction(getActivity());
if (state == 1) {
// jsonobject = new JSONObject(str1);
jsonobject = JSONFunction.getJSONfromURL("url");
JSONObject collection = null;
try {
collection = jsonobject.getJSONObject("collection");
}
catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
JSONArray response = null;
try {
response = collection.getJSONArray("response");
}
catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
for (int i = 0; i < response.length(); i++) {
HashMap<String, String> map = new HashMap<String, String>();
JSONObject jsonobject1 = null;
try {
jsonobject1 = (JSONObject) response.get(i);
noticeId = jsonobject1.getString("id").toString();
noticeTitle = jsonobject1.getString("title").toString();
noticeDescription = jsonobject1.getString("description").toString();
noticePublishedBy = jsonobject1.getString("publishedBy").toString();
noticeValidFrom = jsonobject1.getString("validFrom").toString();
noticeValidTo = jsonobject1.getString("validTo").toString();
Log.e(noticeId, "show");
Log.e(noticeTitle, "show");
Log.e(noticeDescription, "show");
//demo_database.insertData(noticeTitle,noticeDescription,noticePublishedBy,noticeValidFrom,noticeValidTo);
demo_database.insertNoticeData(noticeId,noticeTitle,noticeDescription, noticePublishedBy,
noticeValidFrom, noticeValidTo);
}
catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
else{
onPostExecute(null);
}
return null;
}
#Override
protected void onPostExecute(Void args)
{
// Locate the listview in listview_main.xml
getData();
demo_database.close();
// Close the progressdialog
mProgressDialog.dismiss();
}
}
private void getData() {
// TODO Auto-generated method stub
try {
arraylist = demo_database.fetchNoticeData();
} catch (Exception e) {
e.printStackTrace();
}
listview = (ListView) getActivity().findViewById(R.id.listview);
listview.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View arg1,int arg2, long arg3) {
Toast.makeText(getActivity(), "ListView clicked", Toast.LENGTH_SHORT).show();
}
});
// Pass the results into ListViewAdapter.java
adapter = new NoticeListViewAdapter(getActivity(), arraylist);
// Set the adapter to the ListView
listview.setAdapter(adapter);
}
}

Actually the thing is that when you are trying to access the json through url when internet is not available so the json Array with name response get no items in that so it got Null and when you try to execute For loop in which you give the length of json array it would be crash because of null pointer exception..
Your App is Crashing on the for Loop Right?

How to pass string array to my adapter in android

I am trying to pass a string array to my adapter. My problem is i initialized globally and try to create string array in my asynchronous task below. But i am getting as null. Below is my code. Actually in this example they taking it from resource folders bu i want it from my json response. Any help is appreciated.
String[] mString;
public ActionsAdapter(Context context) {
mInflater = LayoutInflater.from(context);
session = new SessionManager(context);
final Resources res = context.getResources();
new ConnectAppMenu(context).execute();
// mTitles = res.getStringArray(R.array.actions_names);
// mUrls = res.getStringArray(R.array.actions_links);
// mIcons = res.obtainTypedArray(R.array.actions_icons);
System.out.println("Menus"+ mString);
}
public class ConnectAppMenu extends AsyncTask<String, Void, String> {
private ProgressDialog dialog;
private final Context context;
public ConnectAppMenu(Context context) {
this.context = context;
}
#Override
protected void onPreExecute() {
// UI work allowed here
dialog = new ProgressDialog(context);
// setup your dialog here
dialog.setMessage("Connecting....");
dialog.setCancelable(false);
dialog.show();
}
#Override
protected String doInBackground(String... params) {
String returnConnect = doConnectAppMenu();
return returnConnect;
}
public String doConnectAppMenu() {
HashMap<String, String> user = session.getUserDetails();
String client_url = user.get(SessionManager.KEY_CLIENT);
// if(connection) {
HttpParams connectionParameters = new BasicHttpParams();
int timeoutConnection = 8000;
HttpConnectionParams.setConnectionTimeout(connectionParameters, timeoutConnection);
int timeoutSocket = 10000;
HttpConnectionParams.setSoTimeout(connectionParameters, timeoutSocket);
HttpClient httpClient = new DefaultHttpClient(connectionParameters);
HttpPost httpPost = new HttpPost(client_url+"/api/common/app_menu");
JSONObject json = new JSONObject();
try{
json.put("data", 1);
json.put("versionid", 1);
StringEntity se = new StringEntity(json.toString());
se.setContentType(new BasicHeader(HTTP.CONTENT_TYPE, "application/json"));
httpPost.setEntity(se);
//Execute HTTP post request
appmenu_res = httpClient.execute(httpPost);
appmenu_obj = new org.json.JSONObject(org.apache.http.util.EntityUtils.toString(appmenu_res.getEntity()));
appmenu_result = appmenu_obj.toString();
}
catch(JSONException ex) {
// TODO Auto-generated catch block
ex.printStackTrace();
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// }
return appmenu_result;
}
#Override
public void onPostExecute(String result) {
int status_code = appmenu_res.getStatusLine().getStatusCode();
if (status_code == 200) {
dialog.dismiss();
try {
menuObject = new JSONObject(result);
JSONArray names= menuObject.names();
JSONArray values = menuObject.toJSONArray(names);
for (int i = 0; i< values.length(); i++) {
JSONObject json2 = (JSONObject) values.get(i);
int menu_id = json2.getInt("menu_id");
if (menu_id > 0) {
if (json2.has("menu_name")) {
menu_list = json2.get("menu_name").toString();
mString = new String[] { menu_list };
//mUrls = menu_list.length();
}
}
}
System.out.println("Json Menu" + Arrays.toString(mString));
/*Iterator<String> iter = menuObject.keys();
while (iter.hasNext()) {
String key = iter.next();
try {
Object value = menuObject.get(key);
//System.out.println("Hai" +value);
System.out.println("Post Execute" + value);
} catch (JSONException e) {
// Something went wrong!
}
}*/
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//dialog.dismiss();
}
}
}

well first of all if you're looking for the JSON object as a String don't do what you did here:
appmenu_obj = new org.json.JSONObject(org.apache.http.util.EntityUtils.toString(appmenu_res.getEntity()));
I'd suggest doing the following:
String Json = EntityUtils.toString(appmenu_res.getEntity());
return Json;
Now if you want to do the processing of your JSON on the UI thread (as you seem to want to based on the return type being a string) this should work. However this method is not recommended since the Json will need to be processed into objects which will take time and clog the UI thread.
A better solution would be to serialize your Json on the background thread and then pass the serialized object back to the main thread to update the UI.
If you have many types I would suggest using generics. I've already built a Loader which can do what you want if you want here. You will need touse the GSON library and build appropriate seralizers. Also working with the loader class is different to working with the AsyncTaskClass so please read the documentation here
Edit
Ok so what you want to do if you want get the Activity to have a callback from the AsyncTask is to do something along the lines of:
public class MyActivity extends Activity implements AsyncTaskCallback
where AsyncTaskCallback looks something like :
public interface AsyncTaskCallback
{
public processData(Object responseObject);
}
now in your onPostExecute code you'll need to do somehting like:
#Override
protected void onPostExecute(Object r){
if (r != null) {
l.processData(data);
}
}
and add the following function to your async task
public void addAsyncTaskListener (final AsyncTaskListener l){
mCallback = l;
}
and then finally add the listner and process the data as required in the Activity in the function processData function that the interface forces your activity to implement.

Instead of using String[] you can use ArrayList for Setting list in adaptor.

Android App: JSON array from web to listview

I'm just trying to get a simple JSON array in the following format: ["Country1","Country2","Country3"] from the web and then use that array as a listview in my android app. I'm not stuck on how to make this JSON array, i'm just confused on how to get it into a listview in the app.
I have tried a few different tutorials, but none of them are using the same layout as such as mine.
My app is using a viewflipper, to keep a tabbased layout in view at all times throughout the app, therefore none of the tutorials seem to be working with my layout.
Any help is much appreciated.
EDIT:
Here's some code, yes i want to parse it from a web service and display it in a listview.
public class Activity extends TabActivity implements OnClickListener {
Button doSomething;
TabHost tabHost;
ViewFlipper flipper;
ListView listview;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.tablayout_1);
doSomething = (Button) findViewById(R.id.btn_do_something);
doSomething.setOnClickListener(this);
flipper = (ViewFlipper) findViewById(R.id.layout_tab_one);
listview = (ListView) findViewById(R.id.listview);
#SuppressWarnings("unchecked")
ListAdapter adapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1,fetchTwitterPublicTimeline());
//ListAdapter adapter = new SimpleAdapter(this, this.fetchTwitterPublicTimeline() , R.layout.main, new int[] { R.id.item_title, R.id.item_subtitle });
listview.setAdapter(adapter);
flipper.setOnClickListener(this);
String tabname1 = getString(R.string.tabexample_tab1);
String tabname2 = getString(R.string.tabexample_tab2);
String tabname3 = getString(R.string.tabexample_tab3);
String tabname4 = getString(R.string.tabexample_tab4);
tabHost = getTabHost();
tabHost.addTab(tabHost.newTabSpec("tab1").setContent(R.id.layout_tab_one).setIndicator(tabname1));
tabHost.addTab(tabHost.newTabSpec("tab2").setContent(R.id.layout_tab_two).setIndicator(tabname2));
tabHost.addTab(tabHost.newTabSpec("tab3").setContent(R.id.layout_tab_three).setIndicator(tabname3));
tabHost.addTab(tabHost.newTabSpec("tab4").setContent(R.id.layout_tab_four).setIndicator(tabname4));
tabHost.setCurrentTab(0);
listview.setOnItemClickListener(new OnItemClickListener(){
public void onItemClick(AdapterView<?> a, View v, int position, long id) {
flipper.showNext();
}});
}
public ArrayList<String> fetchTwitterPublicTimeline()
{
ArrayList<String> listItems = new ArrayList<String>();
try {
URL twitter = new URL(
"JSON.php");
URLConnection tc = twitter.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(
tc.getInputStream()));
String line;
while ((line = in.readLine()) != null) {
JSONArray ja = new JSONArray(line);
for (int i = 0; i < ja.length(); i++) {
JSONObject jo = (JSONObject) ja.get(i);
listItems.add(jo.getString(""));
}
}
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return listItems;
}
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
}
}
UPDATE: I still can't get it working, any ideas what's wrong in the code below?
public class Activity extends TabActivity implements OnClickListener {
Button doSomething;
TabHost tabHost;
ViewFlipper flipper;
ListView listview;
HttpResponse re;
String json;
JSONObject j;
#SuppressWarnings("deprecation")
#Override
protected void onCreate(Bundle savedInstanceState) {
//final String TAG = "MainActivity";
//final String URL = "JSON.php";
super.onCreate(savedInstanceState);
setContentView(R.layout.tablayout_1);
final String[] listItems = new String[] { };
/*========================================
// JSON object to hold the information, which is sent to the server
JSONObject jsonObjSend = new JSONObject();
try {
// Add key/value pairs
jsonObjSend.put("key_1", "value_1");
jsonObjSend.put("key_2", "value_2");
// Add a nested JSONObject (e.g. for header information)
JSONObject header = new JSONObject();
header.put("deviceType","Android"); // Device type
header.put("deviceVersion","2.0"); // Device OS version
header.put("language", "es-es"); // Language of the Android client
jsonObjSend.put("header", header);
// Output the JSON object we're sending to Logcat:
Log.i(TAG, jsonObjSend.toString(2));
} catch (JSONException e) {
e.printStackTrace();
}
// Send the HttpPostRequest and receive a JSONObject in return
JSONObject jsonObjRecv = HTTPClient.SendHttpPost(URL, jsonObjSend);
String temp = jsonObjRecv.toString();
/*==============================================*/
doSomething = (Button) findViewById(R.id.btn_do_something);
doSomething.setOnClickListener(this);
flipper = (ViewFlipper) findViewById(R.id.layout_tab_one);
listview = (ListView) findViewById(R.id.listview);
/* try {
JSONArray array = jsonObjRecv.getJSONArray(""); //(JSONArray) new JSONTokener(json).nextValue();
String[] stringarray = new String[array.length()];
for (int i = 0; i < array.length(); i++) {
stringarray[i] = array.getString(i);
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, stringarray);
listview.setAdapter(adapter);
} catch (JSONException e) {
// handle JSON parsing exceptions...
}*/
//#SuppressWarnings("unchecked")
ListAdapter adapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1,fetchTwitterPublicTimeline());
//ListAdapter adapter = new SimpleAdapter(this, this.fetchTwitterPublicTimeline() , R.layout.main, new int[] { R.id.item_title, R.id.item_subtitle });
listview.setAdapter(adapter);
flipper.setOnClickListener(this);
String tabname1 = getString(R.string.tabexample_tab1);
String tabname2 = getString(R.string.tabexample_tab2);
String tabname3 = getString(R.string.tabexample_tab3);
String tabname4 = getString(R.string.tabexample_tab4);
tabHost = getTabHost();
tabHost.addTab(tabHost.newTabSpec("tab1").setContent(R.id.layout_tab_one).setIndicator(tabname1));
tabHost.addTab(tabHost.newTabSpec("tab2").setContent(R.id.layout_tab_two).setIndicator(tabname2));
tabHost.addTab(tabHost.newTabSpec("tab3").setContent(R.id.layout_tab_three).setIndicator(tabname3));
tabHost.addTab(tabHost.newTabSpec("tab4").setContent(R.id.layout_tab_four).setIndicator(tabname4));
tabHost.setCurrentTab(0);
listview.setOnItemClickListener(new OnItemClickListener(){
public void onItemClick(AdapterView<?> a, View v, int position, long id) {
flipper.showNext();
}});
}
public ArrayList<String> fetchTwitterPublicTimeline()
{
ArrayList<String> listItems = new ArrayList<String>();
try {
URL twitter = new URL(
"JSON.php");
URLConnection tc = twitter.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(
tc.getInputStream()));
String line = null;
//make sure youe String line is completely filled after that..
if (!line.equals(null) && !line.equals("") && line.startsWith("["))
{
JSONArray jArray = new JSONArray(line);
for (int i = 0; i < jArray.length(); i++)
{
JSONObject jobj = jArray.getJSONObject(i);
// also make sure you get the value from the jsonObject using some key
// like, jobj.getString("country");
listItems.add(jobj.getString(""));
}
}
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return listItems;
}
/* public ArrayList<String> fetchTwitterPublicTimeline()
{
ArrayList<String> listItems = new ArrayList<String>();
try {
URL twitter = new URL(
"JSON.php");
URLConnection tc = twitter.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(
tc.getInputStream()));
//make sure youe String line is completely filled after that..
if (!line.equals(null) && !line.equals("") && line.startsWith("["))
{
JSONArray jArray = new JSONArray(line);
for (int i = 0; i < jArray.length(); i++)
{
JSONObject jobj = jArray.getJSONObject(i);
// also make sure you get the value from the jsonObject using some key
// like, jobj.getString("country");
listItems.add(jobj.getString(""));
}
}
/* String line;
while ((line = in.readLine()) != null) {
JSONArray ja = new JSONArray(line);
for (int i = 0; i < ja.length(); i++) {
JSONObject jo = (JSONObject) ja.get(i);
listItems.add(jo.getString(""));
}
}
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return listItems;
}*/
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
}
}
Update, here are the values of jArray as reported by Logcat:
08-26 16:49:07.246: VERBOSE/app(472): jarray value: ["Country1","Country2","Country3"]
These are the correct values!

This works in a simple test app I just created...
ListView list = (ListView) findViewById(...);
String json = "[\"Country1\",\"Country2\",\"Country3\"]";
try {
JSONArray array = (JSONArray) new JSONTokener(json).nextValue();
String[] stringarray = new String[array.length()];
for (int i = 0; i < array.length(); i++) {
stringarray[i] = array.getString(i);
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, stringarray);
list.setAdapter(adapter);
} catch (JSONException e) {
// handle JSON parsing exceptions...
}

From JSONObject to ListView()

basically I have some data stories in an API in JSON format.
I have managed to get the data from the JSON, loop through the, put them into a TextView, add onClick() on the textView.
but I want to be able to use the optical button on the phone to scroll, so I been told I need a ListView()
So I put the text I want into an array and added the array to the listView
As the example shows below
But how do I add onClick for each Item and pass the ID (intStoryID)?????????
My Code Example
BufferedReader jsonBr = null;
ArrayList arrStoryList = null;
public void onCreate(Bundle savedInstancesState){
super.onCreate(savedInstancesState);
setContentView(R.layout.stories_main);
if(setTopStoryData()){
setStoriesArray();
buildPage();
}else{
// TODO add Error Handling
}
}
public boolean setTopStoryData(){
String strURL = "http://www.example.com/api/index.php?my=params";
JSONConn jsonConn = new JSONConn();
JSONConn.setURL(strURL);
if(jsonConn.setData()){
jsonBr = jsonConn.Br();
return true;
}else{
// my Error Handling
return false;
}
}
public void setStoriesArray(){
String line;
String strAddDate;
String strCurrentStatus;
String strStatusRead;
int intStoryID;
int intNumStories;
arrStoryList = new ArrayList();
JSONObject arrStories;
JSONObject arrAllStories;
JSONObject arrSingleStory;
try{
while((line = jsonBr.readLine()) != null){
arrStories = new JSONObject(line);
intNumStories = Integer.parseInt(arrStories.optString("NumStories"));
arrAllStories = arrStories.getJSONObject("StoryData");
if(intNumStories > 0){
for(int i = 0; i < intNumStories; i++){
arrSingleStory = arrAllStories.getJSONObject("Story"+i);
intStoryID = Integer.parseInt(arrSingleStory.getString("ID"));
strAddDate = arrSingleStory.getString("ADDEDDATE");
strCurrentStatus = arrSingleStory.getString("CURRENTSTATUS");
if(strCurrentStatus.equals("y")){
strStatusRead = "Online";
}else if(strCurrentStatus.equals("n")){
strStatusRead = "Offline";
}else{
strStatusRead = "Pending";
}
String strStoryText = strAddDate+" - " +strCurrentStatus;
arrStoryList.add(strStoryText));
} // end FOR loop
}
} //End while loop
} catch (IOException e) {
// TODO Auto-generated catch block
strDEBUG += "Error (2)";
} catch (JSONException e) {
// TODO Auto-generated catch block
strDEBUG += "Error (3) "+e.getLocalizedMessage()+"\n";
}
}
public void buildPage(){
if(this.arrStoryList != null){
ListView lv1 = (ListView)findViewById(R.id.listView1);
lv1.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,this.arrStoryList));
}
}

use onItemClickListener() to the list view to get click event on each item
listview.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> arg0, View view,
int position, long id) {
// do whatever you want here
}
});