I have a problem with the AsyncTask. Sometimes the doInBackground() method is not called after onPreExecute().
AsyncTask
doInBackground()
onPreExecute()
I know this questio
Your code looks fine.
You can only run async tasks once. I'm guessing that you are trying to run them several times.
Create another instance and try again.
If it doesn't works, check the logcat and post it here if it's not enough for you to fix it.