화면 아래쪽에 framelayout을 놓고 그 안에 코드로 fragment 2개를 추가해서 replace해가면서 사용하려고 합니다. 지금

private BestCommentsFragment bestCommentsFragment;
private RecentCommentFragment recentCommentFragment;

bestCommentsFragment = new BestCommentsFragment().newInstance();
recentCommentFragment = new RecentCommentFragment().newInstance();

getSupportFragmentManager().beginTransaction()
        .replace(R.id.comments_frameLayout, bestCommentsFragment).commit();


@Override
public void onClick(View v) {
    switch (v.getId()) {
        case R.id.best_comments_Txv:
            transactionMenuFragment(bestCommentsFragment);
            Log.e("tag", "    d" + " daf");
            break;
        case R.id.recent_comments_Txv:
            transactionMenuFragment(recentCommentFragment);
            break;
    }
}

/*
프래그먼트 replace 메소드
 */
public void transactionMenuFragment(Fragment fragment) {
    getSupportFragmentManager()
            .beginTransaction()
            .replace(R.id.comments_frameLayout, fragment)
            .addToBackStack(null)
            .commit();
}

이렇게 코딩을 했는데 프래그먼트와 액티비티 간의 통신이 안되는 것 같아요 ㅜ 관리를 어떻게 해야하나요?