clipChildren is not working even though set to false?

One of the parents of your RelativeLayout might be clipping children (sometimes compatibility libraries add a mystery ViewGroup such as NoSaveStateFrameLayout for example). I’ve used something like this in the past with success to disable clip on all parents of a view:

public void disableClipOnParents(View v) {
    if (v.getParent() == null) {
        return;
    }

    if (v instanceof ViewGroup) {
        ((ViewGroup) v).setClipChildren(false);
    }

    if (v.getParent() instanceof View) {
        disableClipOnParents((View) v.getParent());
    }
}