AlertDialog’s setCancelable(false) method not working

Is this your complete code? then please change your code for setting setCancelable(false) like this

void showDialog() {
    DialogFragment newFragment = MyAlertDialogFragment.newInstance(
            R.string..alert_dialog_two_buttons_title);
    newFragment.setCancelable(false);
    newFragment.show(getFragmentManager(), "dialog");
}