Activity and Fragment handle same menu item.

MainActivity.java

public class MainActivity extends Activity {

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.action_a:
                return true;
            case R.id.action_b:
                return true;
        }

        return false;
    }
}

TopFragment.java

public class TopFragment extends Fragment {

    public TopFragment() {}

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setHasOptionsMenu(true);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // This fragment can handle item that except R.id.action_a and R.id.action_b.
        return super.onOptionsItemSelected(item);
    }
}