调用父活动中的方法，并将值返回给fragment

public interface OnDataReceivedListener {
    void onDataReceived(String data);
}

public class MainActivity extends AppCompatActivity implements OnDataReceivedListener {
    // ...

    @Override
    public void onDataReceived(String data) {
        // 处理从Fragment传递回来的数据
    }
}

public class MyFragment extends Fragment {
    private OnDataReceivedListener mListener;

    // ...

    @Override
    public void onAttach(@NonNull Context context) {
        super.onAttach(context);
        if (context instanceof OnDataReceivedListener) {
            mListener = (OnDataReceivedListener) context;
        } else {
            throw new RuntimeException(context.toString()
                    + " must implement OnDataReceivedListener");
        }
    }

    private void sendDataToParentActivity(String data) {
        mListener.onDataReceived(data);
    }
}