Develop Reference

Android ProgressDialog not dismissing from Thread

i'm developing an android App.
The user registration process calls a service that sends an email so it takes several seconds, like 5 or 6 seconds,that's why I execute that task within a thread. The problem is, the Dialog is never dismissing. It stays rolling and the user can do nothing. Here's my code:
try
{
final ProgressDialog progDailog = new ProgressDialog(ActividadAltaUsuario.this);
new Thread(new Runnable()
{
#Override
public void run()
{
try
{
URL url = new URL("slowWS");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
InputStream in = new BufferedInputStream(conn.getInputStream());
String response = IOUtils.toString(in, "UTF-8");
final JSONObject jsonPrincipal = new JSONObject(response);
Boolean success = jsonPrincipal.get("status").toString() == "true";
if (success)
{
ActividadAltaUsuario.this.runOnUiThread(new Runnable() {
#Override
public void run() {
progDailog.show(ActividadAltaUsuario.this, "Sendind email");
}
});
final String idUsuario = jsonPrincipal.get("idUsuario").toString();
URL url2 = new URL("anotherSlowWS");
HttpURLConnection conn2 = (HttpURLConnection) url2.openConnection();
conn2.setRequestMethod("POST");
InputStream in2 = new BufferedInputStream(conn2.getInputStream());
String response2 = IOUtils.toString(in2, "UTF-8");
JSONObject jsonRtaMail = new JSONObject(response2);
//finish();
}
else
{
//finish();
showToast(jsonPrincipal.get("message").toString());
}
ActividadAltaUsuario.this.runOnUiThread(new Runnable() {
#Override
public void run() {
progDailog.dismiss();
}
});
}
catch (Exception e)
{
e.printStackTrace();
}
}
}).start();
}
catch(Exception e)
{
Log.e("log_tag", "Error in http connection" + e.toString());
}
Can anybody help me?
Thanks!

AsyncTask would be a better approach instead of thread, Replace your network call from thread to use AsyncTask. You can use something like this
private class LongOperation extends AsyncTask<Void, Void, Void> {
#Override
protected String doInBackground(Void... params) {
//Main stuff that needs to be done in background
}
#Override
protected void onPostExecute(Void result) {
//Post Execution this method will be called, handle result accordingly
//You can dismiss your dialog here
}
#Override
protected void onPreExecute() {
//Do initialization relative stuff here
// Initialize your dialog here.
}
}
As both onPostExecute() and onPreExecute() work on main thread you can show and dismiss your dialog in this methods.

The UI controls have to be accessed only from the UI thread.
Usually I do this in class that extends AsyncTask
Something like:
public class MyTask extends AsyncTask {
protected void onPreExecute() {
//create and display your alert here
progDialog = ProgressDialog.show(MyActivity.this,"Please wait...", "Logging ...", true);
}
protected Void doInBackground(Void... unused) {
// here is the thread's work ( what is on your method run()
...
// if we want to show some progress in UI, then call
publishProgress(item)
}
protected void onProgressUpdate(Item... item) {
// theoretically you can show the progress here
}
protected void onPostExecute(Void unused) {
//dismiss dialog here where the thread has finished his work
progDialog.dismiss();
}
}
LE:
More detalis about AsyncTask https://developer.android.com/reference/android/os/AsyncTask
check especially the Protected Methods

AsyncTask always Running and it is not finish

This is my class that i have extended from Asynctask:
public class HttpAsyncTaskSendData extends AsyncTask<String, Void, String> {
public interface SendDataCallback {
void onComplete(AsyncTask task,String nidSave, String guid);
void onError(String msg);
}
...
#Override
protected String doInBackground(String... urls) {
Thread.currentThread().setPriority(Thread.MAX_PRIORITY);
return PostJson.POST(urls[0], urls[1]);
}
#Override
protected void onPostExecute(String result) {
if (result != null) {
...
dataCallback.onComplete(this,res.getString("NidSave"), guid);
} else {
dataCallback.onError("No response from server");
}
}
....
}
I am using this class in my activity like this:
sendDataQueue.add(httpAsyncTaskSendData = new HttpAsyncTaskSendData(cur.getString(cur.getColumnIndex("Guid")),
cur.getString(cur.getColumnIndex("SendStateGps")), datasource, database1
, Housing, new HttpAsyncTaskSendData.SendDataCallback() {
#Override
public void onComplete(AsyncTask task ,String nidSave, String guid) {
if (task.getStatus().equals(AsyncTask.Status.FINISHED) &&
!nidSave.equals("00000000-0000-0000-0000-000000000000")) {
sendDataQueue.remove(task);
} else {
queueHasError = true;
}
if (!queueHasError) {
if (sendDataQueue.size() == 0) {
SendGps(nidSave, guid);
}
}
}
#Override
public void onError(String msg) {
queueHasError = true;
toastError(DetailsActivity.this, msg);
}
}).executeOnExecutor((AsyncTask.THREAD_POOL_EXECUTOR),
AppUtil.getConfig(DetailsActivity.this,
MainActivity.SETTING_GEO_SERVICE) + "SaveVisit/",
json.toString()));
My question is why on onComplete callback when i check Asyncktask status , this is in Running mode? and it is not in Finnish.
My onComplete callback called on onPostExecute and in this section my task should be finished its job!!! but still is running? What's is happen and what's my problem?

onPostExecute is not yet finished, thus the state of the AsyncTask is not FINISH
AsyncTask.Status
FINISHED
Indicates that AsyncTask.onPostExecute(Result) has finished.

Series of AsyncTask does not go for execution instantaneously

My MainActivity has 2 views: TextView and a Button. On button click, I am running an AsyncTask which further creates 10 new AsyncTasks for network operations. Every new task creation is delayed by 1 sec. The code is:
public class MainActivity extends ActionBarActivity
{
TextView tv;
Button t;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.textView1);
t = (Button) findViewById(R.id.toggleButton1);
t.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v)
{
getData();
}
});
}
void getData()
{
SuperNetworkAsyncTask s = new SuperNetworkAsyncTask();
s.execute("");
}
private class SuperNetworkAsyncTask extends AsyncTask<String, Void, String>
{
#Override
protected String doInBackground(String... urls)
{
for(int i=0;i<10;i++)
{
{
nTask = new NetworkAsyncTask();
nTask.execute("");
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
return "";
}
#Override
protected void onPostExecute(String result)
{
}
}
private class NetworkAsyncTask extends AsyncTask<String, Void, String>
{
#Override
protected String doInBackground(String... urls)
{
return String.valueOf(System.currentTimeMillis());
}
#Override
protected void onPostExecute(String result)
{
tv.setText(result);
}
}
}
I was expecting that the moment first NetworkAsyncTask execute method is called, it will start execution. But when I run it, I do not find any NetworkAsyncTask begin its execution until the control comes out of SuperNetworkAsyncTask. Is there any way to push the execution of NetworkAsyncTask thread as soon as execute method is called?
Some clarifications:
Why NetworkAsyncTask are created by SuperNetworkAsyncTask? Because If I create the NetworkAsyncTask in main thread, I get my UI freeze for some time.
Why making 10 object? The purpose of NetworkAsyncTask is to read data from a server at interval of 1 sec for n seconds, here n=10.
Part 2: Updates after doing some tests.
Observation 1:
As a fellow Brian shared a way to avoid creating AsyncTasks in nested way, I tried his code:
void getData() {
Runnable runnable = new Runnable() {
#Override
public void run() {
for (int i = 0; i <= 10; i++) {
nTask = new NetworkAsyncTask();
nTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
try {
Thread.sleep(1000);
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
}
};
new Thread(runnable).start();
}
This freezes my UI for few seconds and then the screen is updated in a fraction of second. It is quite surprising to me too.
Observation 2:
With java.lang.Thread, I experimented to make sure that 1) The threads should be executed right away when run() called. 2) The next task will be created only after previous task is finished.
Code:
public static void main(String[] args) {
myThread m;
for (int i=0;i<10;i++)
{
m=new myThread(String.valueOf(i));
m.start();
synchronized (m)
{
try {
m.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
public class myThread extends Thread
{
public String name = "";
public myThread(String n)
{
name = n;
}
public void run()
{
synchronized (this)
{
System.out.println(" Thread Name = " + name);
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
notifyAll();
}
}
}
Output:
Thread Name = 0
Thread Name = 1
Thread Name = 2
Thread Name = 3
Thread Name = 4
Thread Name = 5
Thread Name = 6
Thread Name = 7
Thread Name = 8
Thread Name = 9
Based in this, I updated my NetworkAsyncTask & SuperNetworkAsyncTask as:
private class NetworkAsyncTask extends AsyncTask<String, Void, String>
{
#Override
protected String doInBackground(String... urls)
{
synchronized (this)
{
return String.valueOf(System.currentTimeMillis());
}
}
#Override
protected void onPostExecute(String result)
{
synchronized (this)
{
tv.setText(result);
notifyAll();
}
}
}
private class SuperNetworkAsyncTask extends AsyncTask<String, Void, String>
{
#Override
protected String doInBackground(String... urls)
{
for(int i=0;i<10;i++)
{
nTask = new NetworkAsyncTask();
nTask.execute(url);
synchronized (nTask)
{
try {
nTask.wait();
} catch (InterruptedException e1) {
e1.printStackTrace();
}
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
return "";
}
#Override
protected void onPostExecute(String result)
{
}
}
With this code the wait() keeps on waiting indefinitely.
Finally I replaced:
nTask.execute(url);
with
nTask.executeOnExecutor(THREAD_POOL_EXECUTOR, "");
This worked well as expected.

The UI will be updated only at onPostExecute(). See notes on AsyncTask
Click here! And Try to avoid 10 AysncTasks, it does not make any sense.

You don't need to use a "super async task" use a runnable and then create new async tasks in parallel
void getData() {
Runnable runnable = new Runnable() {
#Override
public void run() {
for (int i = 0; i <= 10; i++) {
nTask = new NetworkAsyncTask();
nTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
try {
Thread.sleep(1000);
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
}
};
new Thread(runnable).start();
}
Post honeycomb you can specify to run async tasks in parallel

An AsyncTask should be started in the UI thread, not on the one doInBackground runs on. You could call publishProgress after every sleep, and spawn each AsyncTask in the resulting calls to onProgressUpdate, which run on the UI thread.

show progress dialog while loading data

I want to show a progress dialog while loading some data from remote server :
I'm using the following thread in order to get the data and it's working, but i'm not able to show the progress bar on the activity:
public class Request {
public String text ;
public boolean downloadText(String urlStr) {
final String url = urlStr;
new Thread () {
public void run() {
int BUFFER_SIZE = 2000;
InputStream in = null;
Message msg = Message.obtain();
msg.what=2;
try {
in = openHttpConnection(url);
InputStreamReader isr = new InputStreamReader(in);
int charRead;
text = "";
char[] inputBuffer = new char[BUFFER_SIZE];
while ((charRead = isr.read(inputBuffer))>0)
{
//---convert the chars to a String---
String readString =
String.copyValueOf(inputBuffer, 0, charRead);
text += readString;
inputBuffer = new char[BUFFER_SIZE];
}
Bundle b = new Bundle();
b.putString("text", text);
msg.setData(b);
in.close();
}catch (IOException e) {
e.printStackTrace();
}
}
}.start();
}
would you please tell me how can i do it !!

create the class as below and just call the object of this class.
class MyTask extends AsyncTask<Void, Void, Void> {
ProgressDialog Asycdialog = new ProgressDialog(ActivityName.this);
#Override
protected void onPreExecute() {
super.onPreExecute();
Asycdialog.setMessage("Loading...");
Asycdialog.show();
}
#Override
protected Void doInBackground(Void... arg0) {
// do the task you want to do. This will be executed in background.
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
Asycdialog.dismiss();
}
}

Use progressDialog
final ProgressDialog progress=ProgressDialog.show(youractivity.this,"","message");
new Thread()
{
public void run()
{
try{
youractivity.this.runOnUiThread(new Runnable(){
#Override
public void run() {
// TODO Auto-generated method stub
// your code
}
});
}
catch(Exception e)
{
}
progress.dismiss();
}
}.start()
Also, note that if you want to use Toast, you should use runOnUiThread

If you do not want to change the structure of your code, you can use runOnUiThread or an Handler to show and dissmiss the progress dialog. Show it when the firs line of the run method is excuted and dismiss it in the finally block.
public void run() {
runOnUiThread(new Runnable() {
public void run(){
// show progress dialog
}
});
/// your code here
try {
} catch (IOException e) {
} finally {
runOnUiThread(new Runnable() {
public void run(){
// dismiss progress dialog
}
});
}
}

Create Progress Dialog in AsyncTask
private class YourAsyncTask extends AsyncTask<Void, Void, Void> {
protected Void doInBackground(Void... args) {
// do background work here
return null;
}
protected void onPostExecute(Void result) {
// do UI work here
}
}

pDialog = ProgressDialog.show(context, null, "Loading...", true);
pDialog.setCancelable(false);
new Thread() {
public void run() {
// handle the exception somehow, or do nothing
// run code on the UI thread
runOnUiThread(new Runnable() {
#Override
public void run() {
try {
// do yor ui part here
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
}.start();

ProgressDialog Android

I am trying to use ProgressDialog. when i run my app the Progress Dialog box show and disappear after 1 second. I want to show it on completion of my process.. Here is my code:
public class MainActivity extends Activity {
android.view.View.OnClickListener mSearchListenerListener;
private ProgressDialog dialog;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new YourCustomAsyncTask().execute(new String[] {null, null});
}
private class YourCustomAsyncTask extends AsyncTask <String, Void, Void> {
protected void onPreExecute() {
dialog = new ProgressDialog(MainActivity.this);
dialog.setMessage("Loading....");
dialog.setIndeterminate(true);
dialog.setCancelable(true);
dialog.show(); //Maybe you should call it in ruinOnUIThread in doInBackGround as suggested from a previous answer
}
protected void doInBackground(String strings) {
try {
// search(strings[0], string[1]);
runOnUiThread(new Runnable() {
public void run() {
// updateMapWithResult(); //Or call it onPostExecute before progressDialog's dismiss. I believe this method updates the UI so it should run on UI thread
}
});
} catch(Exception e) {
}
}
#Override
protected void onPostExecute(Void params) {
dialog.dismiss();
//result
}
#Override
protected Void doInBackground(String... params) {
// TODO Auto-generated method stub
return null;
}
}
}
Updated Question:
#Override
public void onCreate(SQLiteDatabase db) {
mDatabase = db;
Log.i("PATH",""+mDatabase.getPath());
mDatabase.execSQL(FTS_TABLE_CREATE);
loadDictionary();
}
/**
* Starts a thread to load the database table with words
*/
private void loadDictionary() {
new Thread(new Runnable() {
public void run() {
try {
loadWords();
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}).start();
}
private void loadWords() throws IOException {
Log.d(TAG, "Loading words...");
for(int i=0;i<=25;i++)
{ //***//
final Resources resources = mHelperContext.getResources();
InputStream inputStream = resources.openRawResource(raw_textFiles[i]);
//InputStream inputStream = resources.openRawResource(R.raw.definitions);
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
try {
StringBuilder sb = new StringBuilder();
while ((word = reader.readLine()) != null)
{
sb.append(word);
// Log.i("WORD in Parser", ""+word);
}
String contents = sb.toString();
StringTokenizer st = new StringTokenizer(contents, "||");
while (st.hasMoreElements()) {
String row = st.nextElement().toString();
String title = row.substring(0, row.indexOf("$$$"));
String desc = row.substring(row.indexOf("$$$") + 3);
// Log.i("Strings in Database",""+title+""+desc);
long id = addWord(title,desc);
if (id < 0) {
Log.e(TAG, "unable to add word: " + title);
}
}
} finally {
reader.close();
}
}
Log.d(TAG, "DONE loading words.");
}
I want to show ProgressDialogue box untill all words are not entered in the database. This code is in inner calss which extends SQLITEHELPER. so how to can i use ProgressDialogue in that inner class and run my addWords() method in background.

You cannot have this
runOnUiThread(new Runnable() {
public void run() {
// updateMapWithResult(); //Or call it onPostExecute before progressDialog's dismiss. I believe this method updates the UI so it should run on UI thread
}
});
in your doInBackground().
Progress dialog doesn't take priority when there is some other action being performed on the main UI thread. They are intended only when the actions are done in the background. runonUIthread inside doInBackground will not help you. And this is normal behavior for the progressdialog to be visible only for few seconds.

You have two doInBackground() methods inside your AsyncTask Class. Remove the runOnUiThread() from First doInBackground() and move it to second doInBackground() which has #Override annotation.
I don't know whether you wantedly written two doInBackground() methods or by mistake but it is not good to have such confusion between the Method. Your AsyncTask is not calling the first doInBackground() and it will call doInBackground() which has #Override annotation. So your ProgressDialog is dismissed in 1 second of time as it returns null immediately.