addOrRemove

 public void remove(PhotoCard card) {
        int position = getItemPosition(card);
        if (position != -1) {
            mPhotoCards.remove(position);
            notifyItemRemoved(position);
        }
    }

    public void add(PhotoCard card, int position) {
        mPhotoCards.add(position, card);
        notifyItemInserted(position);
    }