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Android - Call an Asynctask from an Asynctask with infinity loop

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.

simple process bar with asytask

I want to add a simple process bar to my code with asy task. I tryed some exampels but cant see that process bar working.
I post here my code hope you can help me.
I want to stop process bar when some of my code is done like with some flag to stop the proses bar.
plese post some code.
thanks a lot!
here my code:
private class loading extends AsyncTask<Void, Void, Integer> {
Context context;
ProgressBar progressBar;
static final long waitTime = 1 * 4000L;
long preTime;
int progress;
public loading(Context context) {
this.context = context;
progressBar = (ProgressBar) findViewById(R.id.progress_bar);
progressBar.setProgress(0);
}
protected void onPostExecute(Integer result) {
Intent intent = new Intent(this.context, first.class);
intent.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
context.startActivity(intent);
finish();
return;
}
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
preTime = System.currentTimeMillis();
}
protected void onProgressUpdate(Integer... values) {
progressBar.setProgress(values[0]);
}
#Override
synchronized protected Integer doInBackground(Void... arg0) {
int waited = 0;
while (waited < 3000) {
try {
// SystemClock.sleep(100);
this.wait(100);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
waited += 100;
}
return null;
}
}

Your doInBackground method needs to call publishProgress() in order for you to update the UI.
After the line waited += 100; add:
int progress = Math.round((float)waited / 3000 * 100);
publishProgress(progress);
Also, the signature of AsyncTask is wrong if you intend on using an integer to reflect your progress. The generic parameters are AsyncTask<Params, Progress, Result>, so in your case, you're not accepting any arguments, or returning any meaningful value from doInBackground, but, you do want to return an Integer to indicate progress. So, change your class declaration to match:
private class loading extends AsyncTask<Void, Integer, Integer>
{
//your implementation
}

You are not calling AsyncTask.publishProgress and that is why your onProgressUpdate method is never called.
And by the way, your class name loading brokes naming conventions, that's not a good practice.

ProgressDialog.dismiss() does not close in Async Class android

I have an inner class that downloads some images from the server. The problem is that the ProgressDialog does not dismiss() onPostExecute() method and don't understand why.
I understand that the progress dialog should be shown onPreExecute() method, and the after the code from the doInBackground() finished , in the onPostExecute() method the dialog should be dismiss. Do you have any idea what i am doing wrong here? Thank you.
/**
* Download images from server
*/
public class DownloadAsyncTask extends AsyncTask<Void, Integer, Void> {
private ProgressDialog mDialog;
// execution of result of Long time consuming operation
protected void onPostExecute(Void result) {
// progressDialog.show();
if (mDialog.isShowing()) {
mDialog.dismiss();
}
}
// Things to be done before execution of long running operation.
protected void onPreExecute() {
mDialog = ProgressDialog
.show(ImagesActivity.this, getString(R.string.pleasewait),
getString(R.string.loading));
}
// perform long running operation operation
protected Void doInBackground(Void... params) {
System.out.println("doInBackground loading.." + id);
String tempPath = FileUtils.createTempFile(id);
for (int i = 0; i < imagePaths.size(); i++) {
imagePaths.get(i).trim();
try {
Bitmap imgTemp;
imgTemp = FileUtils.downloadBitmapFromURL(id,
imagePaths.get(i), tempPath);
System.out.println("imgTemp: " + imgTemp);
if (imgTemp != null) {
// save image on sdcard.
// compress it for performance
Bitmap img = Bitmap.createScaledBitmap(imgTemp, 90, 80,
true);
imgTemp.recycle();
FileUtils.saveDataToFile(img, tempPath,
imagePaths.get(i));
} else {
continue;
}
} catch (IOException e) {
e.printStackTrace();
mDialog.dismiss();
}
}
Looper.prepare();
mDialog.dismiss();
return null;
}
/*
* Things to be done while execution of long running operation is in
* progress.
*/
protected void onProgressUpdate(Integer... values) {
if (mDialog.isShowing()) {
mDialog.dismiss();
}
}
}

actually what you are trying to do is to access the UI Thread from another thread and that is not possible , in your case you are using AsyncTask class enables proper and easy use of the UI thread without having to manipulate threads and/or handlers. use onPostExecute(Result) to access the UI Thread.
so this should work
protected void onPostExecute(Void result) {
progressDialog.show();
if (mDialog.isShowing()) {
mDialog.dismiss();
}
}

I've struggled with this same problem for quite a while. Here is how I got it solved, take a look at this part of the documentation:
A dialog is always created and displayed as a part of an Activity. You
should normally create dialogs from within your Activity's
onCreateDialog(int) callback method. When you use this callback, the
Android system automatically manages the state of each dialog and
hooks them to the Activity, effectively making it the "owner" of each
dialog
Note: If you decide to create a dialog outside of the onCreateDialog()
method, it will not be attached to an Activity. You can, however,
attach it to an Activity with setOwnerActivity(Activity).
from: http://developer.android.com/guide/topics/ui/dialogs.html#ShowingADialog
This is an example of what you have to set on your activity:
#Override
protected void onPrepareDialog(int id, Dialog dialog)
{
//This doesn't do anything
if (id == DIALOG_PROGRESS_ID) {
((ProgressDialog)dialog).setIndeterminate(true);
}
super.onPrepareDialog(id, dialog);
}
#Override
protected Dialog onCreateDialog(int id)
{
if (id == DIALOG_PROGRESS_ID) {
ProgressDialog dialog = new ProgressDialog(this);
dialog.setMessage("Loading");
dialog.setCancelable(false);
dialog.setIndeterminate(true);
return dialog;
}
return null;
}
You can then call
myActivity.showDialog(myActivity.DIALOG_PROGRESS_ID), myActivity.dismissDialog(myActivity.DIALOG_PROGRESS_ID) from any where as long as you have a reference to your activity instance.

Use a handler and onPostExecute() send the handler msg to dismiss the progress dialog.
You can get help from this link ProgressDialog dismissal in android

Your code is working fine but can you check that control are reaching in Post onPostExecute() method I have tried as
package com.alarm.activity;
import android.app.Activity;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.os.Bundle;
public class AlarmManagerActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//set up main content view
setContentView(R.layout.main);
new DownloadAsyncTask().execute();
}
/**
* Download images from server
*/
public class DownloadAsyncTask extends AsyncTask<Void, Integer, Void> {
private ProgressDialog mDialog;
// execution of result of Long time consuming operation
#Override
protected void onPostExecute(Void result) {
// progressDialog.show();
if (mDialog.isShowing()) {
mDialog.dismiss();
}
}
// Things to be done before execution of long running operation.
#Override
protected void onPreExecute() {
mDialog = ProgressDialog.show(AlarmManagerActivity.this, "Hello", "Test");
}
// perform long running operation operation
#Override
protected Void doInBackground(Void... params) {
//System.out.println("doInBackground loading.." + id);
/* String tempPath = FileUtils.createTempFile(id);
for (int i = 0; i < imagePaths.size(); i++) {
imagePaths.get(i).trim();
try {
Bitmap imgTemp;
imgTemp = FileUtils.downloadBitmapFromURL(id, imagePaths.get(i), tempPath);
System.out.println("imgTemp: " + imgTemp);
if (imgTemp != null) {
// save image on sdcard.
// compress it for performance
Bitmap img = Bitmap.createScaledBitmap(imgTemp, 90, 80, true);
imgTemp.recycle();
FileUtils.saveDataToFile(img, tempPath, imagePaths.get(i));
}
else {
continue;
}
}
catch (IOException e) {
e.printStackTrace();
mDialog.dismiss();
}
}
Looper.prepare();
mDialog.dismiss();*/
try {
Thread.sleep(5000);
}
catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
/*
* Things to be done while execution of long running operation is in
* progress.
*/
#Override
protected void onProgressUpdate(Integer... values) {
if (mDialog.isShowing()) {
mDialog.dismiss();
}
}
}
}
I think problem in doInbackground() method. I have simply run thread for sleep 5 sec and after control reaches in post() method and dissmiss progress dialog.

View ProgressBar on Gallery Intent

I'm using these codes to view an image from my application:
Intent intent = new Intent();
intent.setAction(android.content.Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(imgFile), "image/*");
startActivity(intent);
I have no problem viewing the picture but when the size is a little bit larger, the intent keeps blank until the image is ready to load and show.
My question is, how can I show a ProgressBar, or in more advanced way, show a temporary image, before the real image get shown?
Thanks for the answer.

Try Asynctask as shown here:
try{
class test extends AsyncTask{
TextView tv_per;
int mprogress;
Dialog UpdateDialog = new Dialog(ClassContext);
#Override
protected void onPreExecute() {
// TODO Auto-generated method stub
mprogress = 0;
UpdateDialog.setTitle(getResources().getString(R.string.app_name));
UpdateDialog.setContentView(R.layout.horizontalprogressdialog);
TextView dialog_message = (TextView)UpdateDialog.findViewById(R.id.titleTvLeft);
tv_per = (TextView)UpdateDialog.findViewById(R.id.hpd_tv_percentage);
dialog_message.setText(getResources().getString(R.string.dialog_retrieving_data));
dialog_message.setGravity(Gravity.RIGHT);
UpdateDialog.setCancelable(false);
UpdateDialog.show();
super.onPreExecute();
}
#Override
protected void onProgressUpdate(Object... values) {
// TODO Auto-generated method stub
ProgressBar update = (ProgressBar)UpdateDialog.findViewById(R.id.horizontalProgressBar);
update.setProgress((Integer) values[0]);
int percent = (Integer) values[0];
if(percent>=100)
{
percent=100;
}
tv_per = (TextView)UpdateDialog.findViewById(R.id.hpd_tv_percentage);
tv_per.setText(""+percent);
}
#Override
protected Object doInBackground(Object... params) {
// TODO Auto-generated method stub
//your code of UI operation
}
super.onPostExecute(result);
UpdateDialog.dismiss();
}
}
new test().execute(null);
}
catch(Exception e)
{
e.printStackTrace();
}
Also refer to this link: Fetch data from server and refresh UI when data is fetched?:)

Using of Toast with thread in android

progressDialog = ProgressDialog.show(GetResponse.this, "", "Loading...");
new Thread()
{
public void run()
{
try
{
// inside i have written code for making connection to the server using SSL connection.
}catch (Exception e)
{
progressDialog.dismiss();
exception(e.getMessage())
}.start();
}
private void exception(String msg)
{
Toast.makeText(this, msg, Toast.LENGTH_LONG).show();
this.finish();
Intent i = new Intent(getBaseContext(), LoginPage.class);
startActivity(i);
}
my LoginPage.java is previous activity.
If the connection is successfull it goes to the next activity ot doesnt give any error,
But if der is any prob with connection then i want progress bar should be stopped and go back to the LoginPage activity and also i want the error msg to be displayed.
From the above im getting some error.. Please help me out on this

Pass in and use the context from LoginPage. Also, use the 101010 button to format your code as code in your posts.

you can go up by using try catch mechanism where in your catch place your toast message and u can do it also by asynchronous task,
here simple code
private class Task_News_ArticleView extends AsyncTask<Void, Void, Void> {
private final ProgressDialog dialog = new ProgressDialog(
Bru_Sports_View.this);
// can use UI thread here
protected void onPreExecute() {
this.dialog.setMessage("Loading...");
this.dialog.setCancelable(false);
this.dialog.show();
}
#Override
protected Void doInBackground(Void... params) {
try {
//here the condition to check login details
}
} catch (Exception e) {
}
return null;
}
protected void onPostExecute(Void result) {
if (this.dialog.isShowing()) {
this.dialog.dismiss();
}
}
}
and u can also use try,catch in catch block you can place your toast message
with finsih() method