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POAndroid AsyncTask threads limits?
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copied!<p>I am developing an application where I need to update some info every time user logs in to the system, I also use database in the phone. For all those operations (updates, retrieving data from db and etc.) I use async tasks. As up till now I didn't see why I shouldn't use them, but recently I experienced that if I do some operations some of my async tasks simply stop on pre-execute and don't jump to doInBackground. That was just too strange to leave it like that, so I developed another simple application just to check whats wrong. And strange enough, I get the same behavior when count of total async tasks reach 5, the 6th one stops on pre-execute.</p> <p>Does android have a limit of asyncTasks on Activity/App? Or is it just some bug and it should be reported? Did anyone experience the same problem and maybe found a workaround to it?</p> <p>Here is the code:</p> <p>Simply create 5 of those threads to work in a background:</p> <pre><code>private class LongAsync extends AsyncTask<String, Void, String> { @Override protected void onPreExecute() { Log.d("TestBug","onPreExecute"); isRunning = true; } @Override protected String doInBackground(String... params) { Log.d("TestBug","doInBackground"); while (isRunning) { } return null; } @Override protected void onPostExecute(String result) { Log.d("TestBug","onPostExecute"); } } </code></pre> <p>And then create this thread. It will enter preExecute and hang (it will not go to doInBackground).</p> <pre><code>private class TestBug extends AsyncTask<String, Void, String> { @Override protected void onPreExecute() { Log.d("TestBug","onPreExecute"); waiting = new ProgressDialog(TestActivity.this); waiting.setMessage("Loading data"); waiting.setIndeterminate(true); waiting.setCancelable(true); waiting.show(); } @Override protected String doInBackground(String... params) { Log.d("TestBug","doInBackground"); return null; } @Override protected void onPostExecute(String result) { waiting.cancel(); Log.d("TestBug","onPostExecute"); } } </code></pre>

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