Android - Call an Asynctask from an Asynctask with infinity loop - android

I have 2 Asynctask, 1 for get data (location) from server then set a marker on map with this location and another call 1st Asyntask in a loop for updating location.
Here my code:
public class AsynComp extends AsyncTask<Void, Void, Void> {
ProgressDialog taxiDialog;
#Override
protected Void doInBackground(Void... params) {
jsonComp = new JSONComp(find_url);
find_status = jsonComp.getJsonStatus(txt_search);
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
if (find_status.equals("2013")) {
Toast.makeText(getBaseContext(), "no result",
Toast.LENGTH_SHORT).show();
} else if (find_status.equals("2012")) {
for (Marker marker:markers){
if(marker.getTitle().equals(compFollow)){
marker.remove();
}
}
for (int i=0; i<number;i++){
comp = new Comp(jsonComp.getJsondata(i));
SetMarkerComp(comp);
try {
Thread.sleep(1400);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
}
public class AsynFollow extends AsyncTask<Void, Void, Void> {
#Override
protected Void doInBackground(Void... params) {
if (!taxiFollow.equals("")) {
number = 1;
txt_search = compFollow;
find_url = "http://192.111.125.80:8001/Default.aspx?username="
+ Id + "&password=" + Pass + "&sohieuxe="+txt_search;
while (!stop){
new AsynComp().execute();
try {
Thread.sleep(1500);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
taxiFollow = "";
}
return null;
}
protected void onPostExecute(Void result) {
super.onPostExecute(result);
if (!compFollow.equals("")) {
Toast.makeText(getBaseContext(), "Follow "+compFollow, Toast.LENGTH_SHORT).show();
} else {
iv_theodoi.setVisibility(View.VISIBLE);
iv_theodoif.setVisibility(View.GONE);
Toast.makeText(getBaseContext(), "Plz choose a marker", Toast.LENGTH_SHORT).show();
}
}
}
And i have 2 buuton, 1 to call AsynFollow.execute(), another to stop it.
This code can run but app will force close after awhile.
Any solution? thanks.
P/s: i'm a newbie in android.

You shoulnd you asyncTask for this. For repetitive action, like changing status in some interval, use Timer class. In this way you can implement repetitive action which can be repeated in intervals.
In this way you can stop this time by on click listener. You can run two times and specify it's realtions using other variables.
If you're newbe, you should read about multitasking in Android: Timer, AsyncTask, Handler.
In my opinion this docs will tell you much more than thousands of comments in stackoverflow.

Related

java.lang.IllegalStateException:The content of the adapter has changed but ListView did not receive a notification

*java.lang.IllegalStateException: The content of the adapter has changed but ListView did not receive a notification. Make sure the content of your adapter is not modified from a background thread, but only from the UI thread.
1.My app is Navigation app using GPS location, marker will animate from source to destination according to user car drive, hence the highway details will get populated using RightsideDrawer listview in same activity, once the current location fetched: it automatically updates the nearby shop location in right side listview with its detail and update distance calculation using current location for all list items in listview(in RightNavigationSubViewAdapter -customadapter class).
2.Location updates for every 3000ms, CurrentLocationUpdateList is called for 3 sec once. while updating rightside drawer sublistview (when user is in driving) it occurs crash on some mobiles like Micromax TAB, Samsung Grand Prime and HTC 4.4.2. while driving, Only these mobiles occuring crash on very rare case, i need to fix it soon. kindly help me to resolve it.
#Override
public void onLocationChanged(Location location) {
try {
mCurrentLocation = location;
Singleton.getInstance().mCurrentLocation = location;
final LatLng position = new LatLng(location.getLatitude(), location.getLongitude());
if (isMapReady) {
runOnUiThread(new Runnable() {
#Override
public void run() {
try {
CurrentLocationUpdateList();
} catch (Exception e) {
Log.d(TAG_MSG, "Error", e);
e.printStackTrace();
}
checkAlertView();
updateMarker(mCurrentLocation);
updateCamera(position);
updatePolyLine(position);
}
});
}
} catch (Exception e) {
Log.d(TAG_MSG, "Error", e);
e.printStackTrace();
}
}
3.Right Side Drawer Layout for sublistview, when rightside drawer is opened below functionality will do its UpdateRightSideOpenView work. i.e Singleton.getInstance().drawerOpenRightSubList = true.
public void CurrentLocationUpdateList {
if (Singleton.getInstance().drawerOpenRightSubList) {
try {
new UpdateRightSideOpenView().execute();
}
catch (IllegalStateException e) {
e.printStackTrace();
}
}
else {
try {
new UpdateRightSideSubView().execute();
}
catch (IllegalStateException e) {
e.printStackTrace();
}
}
}
4.Right side Subview func call, RightNavigationSubViewAdapter is used for open right drawer, RightNavigationViewAdapter is used for closed right drawer, 2 adapter for 2 listview, one is for drawer open view and another is for drawer closed view, hence openview will get extra data.
public class UpdateRightSideOpenView extends AsyncTask<Void, Void, Void> {
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... params) {
return null;
}
protected void onPostExecute(Void result) {
try {
subAdapter = new RightNavigationSubViewAdapter(mContext, wayPoints);
mListSub.setAdapter(subAdapter);
mListSub.requestLayout();
subAdapter.notifyDataSetChanged();
adapter = new RightNavigationViewAdapter(mContext, wayPoints);// load new data
adapter.notifyDataSetChanged();
mList.requestLayout();
}
catch (IllegalStateException e) {
e.printStackTrace();
}
}
}
public class UpdateRightSideSubView extends AsyncTask<Void, Void, Void> {
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... params) {
return null;
}
protected void onPostExecute(Void result) {
try {
/*mListSub.invalidateViews(); *///invalidate old
subAdapter = new RightNavigationSubViewAdapter(mContext, wayPoints);
mListSub.setAdapter(subAdapter);
subAdapter.notifyDataSetChanged(); // call notifydatasetChanged
}
catch (IllegalStateException e) {
e.printStackTrace();
}
}
}

How to set time out for AsyncTask execution?

I have been trying to create time out while AsyncTask execution more than 1 minute. If the time up, then should exit with Notification.
This is my code:
private class GetLongLat extends AsyncTask<Void, Void, Void> {
#Override
protected void onPreExecute() {
super.onPreExecute();
longlatDialog = new ProgressDialog(MainActivity.this);
longlatDialog.setMessage("Fetching Data. Please wait..");
longlatDialog.setCancelable(false);
longlatDialog.show();
}
#Override
protected Void doInBackground(Void... arg0) {
GPSTracker gpsTracker;
//This is the timer to set time out
Timer timer = new Timer();
timer.schedule(new TaskKiller(this), 3000);
timer.cancel();
do{
gpsTracker = new GPSTracker(MainActivity.this);
gpsTracker.getLocation();
}while(!String.valueOf(gpsTracker.latitude).equals("0.0"));
return null;
}
protected void onCancelled() {
// do something, inform user etc.
Toast.makeText(getApplicationContext(), "Failed getting long lat. Please check your internet connection", Toast.LENGTH_LONG).show();
System.exit(1);
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
if (longlatDialog.isShowing())
longlatDialog.dismiss();
}
}
And this is a class called in doInBackground to set the time up.
class TaskKiller extends TimerTask {
private AsyncTask<?, ?, ?> mTask;
public TaskKiller(AsyncTask<?, ?, ?> task) {
this.mTask = task;
}
public void run() {
mTask.cancel(true);
}
}
But when i run the code, nothing happen. I mean the progress dialog always run very long time.
EDIT
I have edit my code to call GetLongLat something like this:
GetLongLat n = new GetLongLat();
n.execute();
try {
n.get(3000, TimeUnit.MILLISECONDS);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ExecutionException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (TimeoutException e) {
// TODO Auto-generated catch block
Toast.makeText(getApplicationContext(), "Failed getting long lat. Please check your internet connection", Toast.LENGTH_LONG).show();
System.exit(1);
}
But also, doesn't work.
I think you can use AsyncTask.get()
GetLongLat n = new GetLongLat();
n.get(30000, TimeUnit.MILLISECONDS);
you will have to use the n.get in a separate Thread..
Edited: one more different method but not efficient.,
GetLongLat n = new GetLongLat();
n.execute();
Handler handler = new Handler();
handler.postDelayed(new Runnable()
{
#Override
public void run() {
if ( n.getStatus() == AsyncTask.Status.RUNNING )
n.cancel(true);
}
}, 30000 );
why are you canceling the timer? just after calling schedule()?
Cancels the Timer and all scheduled tasks
timer.cancel(); should be removed. check docs for cancel()
You can achieve this behaviour in many ways.
Here's an example using CountDownTimer
// Start your AsyncTask
private YourAsyncTask mTask = new YourAsyncTask().execute();
// Run a timer after you started the AsyncTask
new CountDownTimer(60000, 1000) {
public void onTick(long millisUntilFinished) {
// Do nothing
}
public void onFinish() {
mTask.cancel(true);
}
}.start();
You are cancelling the timer just after initiating it. You can do it like this too. But this type of busy waiting is not recommended at all.
#Override
protected Void doInBackground(Void... arg0) {
GPSTracker gpsTracker;
//This is the timer to set time out
new CountDownTimer(60000, 1000) {
public void onTick(long millisUntilFinished) {
// Do nothing
}
public void onFinish() {
// Set latitude to zero to finish the while loop outside.
// gpsTracker.latitude = "0.0"; // Something like this
}
}.start();
do{
gpsTracker = new GPSTracker(MainActivity.this);
gpsTracker.getLocation();
}while(!String.valueOf(gpsTracker.latitude).equals("0.0"));
return null;
}
Here's another approach. In your doInBackground method, you can use System.currentTimeMillis to check whether 1 minute has elapsed or not.
protected Void doInBackground(Void... arg0) {
GPSTracker gpsTracker;
long startTime = System.currentTimeMillis();
do{
gpsTracker = new GPSTracker(MainActivity.this);
gpsTracker.getLocation();
}while(!String.valueOf(gpsTracker.latitude).equals("0.0")
&& ((System.currentTimeMillis() - startTime) <= 60000);//60000 millisecond = 1 minute
return null;
}
`
Just alter your code like this and check whether your async task is getting cancelled or not.
GetLongLat getLongLatAsync = new GetLongLat();
getLongLatAsync.execute();
try {
Handler handler = new Handler();
/** 1st method **/
handler.postDelayed(new Runnable()
{
#Override
public void run() {
if (getLongLatAsync.getStatus() == AsyncTask.Status.RUNNING )
getLongLatAsync.cancel(true);
}
}, 3000 ); //3 Seconds
/** 1st method ends **/
/** second method */
handler.post(new Runnable()
{
#Override
public void run() {
getLongLatAsync.get(3000, TimeUnit.MILLISECONDS);//You should run it in seperated thread or else it will block ui thread.
}
});
/** Second method ends**/
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ExecutionException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (TimeoutException e) {
// TODO Auto-generated catch block
Toast.makeText(getApplicationContext(), "Failed getting long lat. Please check your internet connection", Toast.LENGTH_LONG).show();
}
and in the onCancelld method write your logic
#Override
protected void onCancelled() {
Log.d(TAG,"Asynctask has been cancelled.");
}

how to make one asynctask to start after the other one?

what i have is two asynctask each one call a function to parse some data ... and i want the asynctask starts after asynctasknew finish how can i do this??? here is my code ..
send.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
AsyncCallWS task = new AsyncCallWS();
try{
Intent newintent = getIntent();
mixlist=newintent.getStringArrayListExtra("listmix");
Log.e("listmix",mixlist+"");
for(int i=0;i<=mixlist.size();i++){
if(i==mixlist.size()){
Log.d("states","finished");
Item_Name="0";
Item_Price="0";
Item_Quantity="0";
Total_Price="0";
Customer_Name=name.getText().toString();
Log.e("customer_name",Customer_Name);
Customer_Number=mobile.getText().toString();
Customer_Address=addressnew.getText().toString();
//Call execute
task.execute();
}
else{
Item_Name=mixlist.get(i);
i++;
Item_Price=mixlist.get(i);
i++;
Item_Quantity=mixlist.get(i);
i++;
Total_Price=mixlist.get(i);
Customer_Name="0";
Customer_Number="0";
Customer_Address="0";
// AsyncCallWSnew tasknew = new AsyncCallWSnew();
//Call execute
AsyncCallWSnew tasknew = new AsyncCallWSnew();
tasknew.execute();
}
}
}
catch(Exception e){
e.printStackTrace();
}
}
});
}
private class AsyncCallWS extends AsyncTask<Void, Void, Void> {
protected void onPostExecute(Void result) {
//Make Progress Bar invisible
Toast.makeText(getApplicationContext(), "order has been sent + item price", Toast.LENGTH_LONG).show();
Intent intObj = new Intent(PersonalInfo.this,MainActivity.class);
startActivity(intObj);
//Error status is false
}
//Make Progress Bar visible
protected void onPreExecute() {
}
#Override
protected Void doInBackground(Void... params) {
// TODO Auto-generated method stub
loginStatus = WebService.invokeLoginWS(Item_Name,Item_Price,Item_Quantity, Total_Price, Customer_Name,
Customer_Number, Customer_Address,"InsertData");
return null;
}
}
private class AsyncCallWSnew extends AsyncTask<Void, Void, Void> {
protected void onPostExecute(Void result) {
//Make Progress Bar invisible
Toast.makeText(getApplicationContext(), "order has been sent", Toast.LENGTH_LONG).show();
Intent intObj = new Intent(PersonalInfo.this,MainActivity.class);
startActivity(intObj);
//Error status is false
}
//Make Progress Bar visible
protected void onPreExecute() {
}
#Override
protected Void doInBackground(Void... params) {
// TODO Auto-generated method stub
loginStatus = WebService.invokeLoginWS(Item_Name,Item_Price,Item_Quantity, Total_Price, Customer_Name,
Customer_Number, Customer_Address,"InsertData");
return null;
}
}
}
when i make a debug my code works just fine .. but in normal run .. it doesn't can any help me?
There are basically two possibilities:
Simply start the next AsyncTask from onPostExecute() of the previous one
Use AsyncTask.executeOnExecutor() with SerialExecutor and start all of them in a row.
Hi You can use AsyncTask executeonExecutor method to start the async task. But it will require minimum API version 11. Kindly refer the following code.
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
new YourFirstTask().executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,params...);
new YourSecondTask().executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR,params...);
}else{
new YourFirstTask().execute(params...);
new YourSecondTask().execute(params...);
}
For Lower version you can call directly. automatically system will process one by one.

Main UI freezes even when tasks are handled by AsyncTask

I made Service that runs on the background collecting data from internet using AsyncTask and storing them in Shared Preferences. Even though the work is done in AsyncTask it still freezes my main activity.
Here is the code for Service:
public class GetterService extends Service {
SharedPreferences.Editor editor;
HashMap<Integer,String> links = new HashMap<Integer,String>();
#Override
public void onCreate() {
editor = PreferenceManager.getDefaultSharedPreferences(this).edit();
populateLinks();
}
private void populateLinks(){
// Here I add links to HashMap
}
#Override
public IBinder onBind(Intent intent) {
Toast.makeText(this, "GetterService ON BIND", Toast.LENGTH_LONG).show();
return null;
}
#Override
public void onDestroy() {
super.onDestroy();
Toast.makeText(this, "GetterService ON DESTROY", Toast.LENGTH_LONG).show();
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
doTasks();
return super.onStartCommand(intent, flags, startId);
}
#Override
public boolean onUnbind(Intent intent) {
Toast.makeText(this, "GetterService ON UNBIND", Toast.LENGTH_LONG).show();
return super.onUnbind(intent);
}
private void doTasks(){
for (Integer in : links.keySet()) {
Document doc = null;
try {
doc = new NetTask().execute(links.get(in)).get();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ExecutionException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if (doc != null) {
Elements names = doc.select("strong, li");
if(names != null && names.size() > 0) {
for (int j = 0; j < names.size(); j++) {
editor.putString("header"+j, names.get(j).text().toString());
}
}
editor.commit();
}
}
}
public class NetTask extends AsyncTask<String, Integer, Document>
{
#Override
protected Document doInBackground(String... params)
{
Document doc = null;
try {
doc = Jsoup.connect(params[0]).timeout(5000).get();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return doc;
}
}
}
and here is how I start the service from main activity:
Intent startServiceIntent = new Intent(this, GetterService.class);
this.startService(startServiceIntent);
Even though the work is done in AsyncTask it still freezes my main activity.
You are using get():
doc = new NetTask().execute(links.get(in)).get();
And get() blocks the UI thread until the AsyncTask has completed, to me this method defeats the purpose of using a AsyncTask...
You should move this logic:
if (doc != null) {
Elements names = doc.select("strong, li");
if(names != null && names.size() > 0) {
for (int j = 0; j < names.size(); j++) {
editor.putString("header"+j, names.get(j).text().toString());
}
}
editor.commit();
}
Inside your NetTask's onPostExecute() method and remove get(). Now your AsyncTask won't bind-up the main thread.
It's because of the
new NetTask().execute(links.get(in)).get();
call.
AsyncTask.get() blocks until the async call has been completed. To be asynchronous you need to implement
onPostExecute()
and process the results there.
Don't call get(), just call execute(). Implement and overridden onPostExecute() to take a Document object as a parameter. onPostExecute() is called automatically when doInBackground() returns. Code in onPostExecute() is executed on the UI thread, so you can interact with the UI that way.
I suggest you take a look at the AsyncTask section in this document, http://developer.android.com/guide/components/processes-and-threads.html and the AsyncTask API page here, http://developer.android.com/reference/android/os/AsyncTask.html.
I had the similar problem and figured out what's going on. This code will not freeze UI, but if you put 'for loop' and sleep inside onProgressUpdate, then UI will be frozen during the process.
public class Karaoke extends AsyncTask<Void, Integer, Void> {
private Handler mHandler = new Handler(Looper.getMainLooper());
protected Void doInBackground(Void... urls) {
animating = true;
{
for (int i = 0;i < 6; i++)
{
publishProgress(i);
try
{
Thread.sleep(1000);
publishProgress(i);
}
catch (Exception xx){
}
}
}
animating = false;
return null;
}
#Override
protected void onProgressUpdate(Integer... values) {
if (light)
{
light = false;
iv_array[findview(egtxts[values[0]].getText() + "")].setImageResource(onpress);
}
else
{
light = true;
iv_array[findview(egtxts[values[0]].getText() + "")].setImageResource(onup);
}
}
protected void onPostExecute(Long result) {
//showDialog("Downloaded " + result + " bytes");
}
}

asyncTask and progressDialog : Freeze

please see my code .. and if you can, tell me why my progressDialog stopped when the function is halfway done in the background, the screen hangs (nothing is displayed, the logcat shows all logs i put in the background function).
Then, right before the end, the progressDialog starts animating again and closes after a couple seconds (the function is finished and the result is displayed normally)
public class changeWall extends AsyncTask<Integer, Integer, Integer> {
protected Integer doInBackground(Integer... urls) {
int totalSize=0;
try {
if(s.loadBoolean() == false)
{
log("IF = false");
log("tempLogin = "+tempLogin);
log("tempPassword = "+tempPassword);
getNewResponse(tempLogin,tempPassword);
if(needSave)
{
s.saveBoolean(true);
}
}
else
{
if(s.loadLogin()==null)
{
getNewResponse(tempLogin,tempPassword);
}else
{
getNewResponse(s.loadLogin(),s.loadPassowrd());
}
}
parser.setLol(0);
parser.startParse(RESULT_STRING);
log("end parse");
} catch (ClientProtocolException e) {
log("internet connection lost");
} catch (IOException e) {
// TODO Auto-generated catch block
log(" connection lost");
}
log("count = "+parser.getFacebookId(1));
publishProgress();
totalSize=1;
log("end of start");
return totalSize;
}
protected void onProgressUpdate(Integer... progress) {
log("wall click ON PROGRESS UPDATE");
wall.setBackgroundResource(R.drawable.tabbuttonon);
messages.setBackgroundResource(0);
activity.setBackgroundResource(0);
profile.setBackgroundResource(0);
l1_1.setBackgroundResource(R.drawable.tabbuttononleft);
l1_2.setBackgroundResource(R.drawable.tabbuttononright);
l2_1.setBackgroundResource(0);
l2_2.setBackgroundResource(0);
l3_1.setBackgroundResource(0);
l3_2.setBackgroundResource(0);
l4_2.setBackgroundResource(0);
l4_2.setBackgroundResource(0);
wall.setTextColor(Color.BLACK);
messages.setTextColor(Color.WHITE);
profile.setTextColor(Color.WHITE);
activity.setTextColor(Color.WHITE);
try {
loadWall();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
wallProgres.dismiss();
}
protected void onPostExecute(Long result) {
if(result==1)
{
log("end WallChange");
}
}
}
simple map as this showed :
----start progress(progress.show())
----start function
--- animation (progressDialog)
---animation(---)
---animation(---)
---FREEZ
---FREEZ(Function steel working normal, progressDialog in freeze mode)
---animation
---end function
---progress.dismis();//
similar problem i found here..(this problem = my problem but without download) Freezing UI Thread with AsyncTask
Regards,Peter.
It may not be correct but place
wallProgres.dismiss();
in onPostExecute rather than in onProgessUpdate method.
beacuse onProgressUpdate calls while running , but onPostExecute calls after execution.
Hope it helps..
place this line "wallProgres.dismiss()" in onPostExecute().
protected void onPostExecute(Long result) {
if(result==1)
{
log("end WallChange");
}
if(wallProgress.isShowing())
wallProgres.dismiss();
}
put this line
wallProgres.dismiss();
in onPostExecute() method
protected void onPostExecute(Long result) {
if(result==1)
{
log("end WallChange");
wallProgres.dismiss();
}
}

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