private View rootView;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    if (rootView == null){
        rootView = inflater.inflate(R.layout.fragment_on_visit, container, false);
        ButterKnife.bind(this, rootView);
        init();
    }else {
        return rootView;
    }
    return rootView;
}