Fragment へBACK押下時イベントを通知する (Android)

BackPressedListener.java

public interface BackPressedListener {
    void onBackPressed();
}

TestActivity.java

// Activity
@Override
public void onBackPressed() {
    Fragment fragment = getFragmentManager().findFragmentByTag("");
    if (fragment != null && fragment instanceof BackPressedListener) {
        ((BackPressedListener) fragment).onBackPressed();
    } else {
        super.onBackPressed();
    }
}

TestFragment.java

// Fragment (implements BackPressedListener)
@Override
public void onBackPressed() {
    //TODO BACK押下時処理
}

Thanks. your code doesn't work on nested fragment sir. can you help me for this quastion?