Question

Is it possible to cancel AsyncTask that has one line command in doInBackground that performs a very long operation,like

@Override
protected Boolean doInBackground(String... filename) {
    fetchfile(filename[0]);
    // ...
    // ...
    return ...;
}

Answer 1

You can AsyncTask.cancel() to cancel. You can cancel it inside the fetchFile method at an appropriate place where you feel it will not introduce inconsistencies in your data or at a place where its easier to rollback.