AsyncTask will always run even if app is destroyed?
I have an application and because you can't do network operations on the main thread I'm using AsyncTask, so the question is once I execute() the AsyncTask and right after that I finish() the activity, and maybe the user will finish() the whole app, so what I'm wondering is:
- Will
AsyncTaskalways finishdoInBackground()andonPostExecute()even if the app is closed as long asexecute()was called when the app was running?
Answer
You will be able to test this. And yes It does. If execute was called you can see Asynctask will still execute UNLESS it does something to the forground or UI related. (it may cause launcher to crash).
However, if it was close by the system. It may or may not continue executing the method. I have already tested and answered here.
Reply to comment:
Tested:
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new Worker().execute();
}
private class Worker extends AsyncTask<Void, Void, String> {
@Override
protected String doInBackground(Void... arg0) {
Log.i("SomeTag",
"start do in background at " + System.currentTimeMillis());
String data = null;
try {
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(
"https://stackoverflow.com/questions/tagged/android");
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
data = EntityUtils.toString(httpEntity);
Log.i("SomeTag",
"doInBackGround done at " + System.currentTimeMillis());
} catch (Exception e) {
}
return data;
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
Log.i("SomeTag", System.currentTimeMillis() / 1000L
+ " post execute \n" + result);
}
}
@Override
protected void onDestroy() {
super.onDestroy();
Log.i("SomeTag", System.currentTimeMillis() / 1000L + " onDestory()");
}
04-24 21:42:57.981: I/SomeTag(5961): start do in background at 1366854177994
04-24 21:43:00.974: I/SomeTag(5961): 1366854180 onDestory()
04-24 21:43:02.946: I/SomeTag(5961): doInBackGround done at 1366854182946
04-24 21:43:02.946: I/SomeTag(5961): 1366854182 post execute
04-24 21:43:02.946: I/SomeTag(5961): <!DOCTYPE html>
04-24 21:43:02.946: I/SomeTag(5961): <html>
04-24 21:43:02.946: I/SomeTag(5961): <head>
04-24 21:43:02.946: I/SomeTag(5961):
04-24 21:43:02.946: I/SomeTag(5961): <title>Newest 'android' Questions - Stack Overflow</title>
04-24 21:43:02.946: I/SomeTag(5961): <link rel="shortcut icon" href="http://cdn.sstatic.net/stackoverflow/img/favicon.ico">
//....