如何通过屏幕旋转来存储分页视图的状态

public class MainActivity extends AppCompatActivity {
    private static final String KEY_PAGE_INDEX = "page_index";
    private int pageIndex;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        if (savedInstanceState != null) {
            // 从savedInstanceState中恢复之前保存的状态数据
            pageIndex = savedInstanceState.getInt(KEY_PAGE_INDEX);
        } else {
            // 初始化默认状态
            pageIndex = 0;
        }

        // 根据pageIndex显示对应的分页视图
        showPage(pageIndex);
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        // 将pageIndex保存到Bundle中
        outState.putInt(KEY_PAGE_INDEX, pageIndex);
    }

    private void showPage(int index) {
        // 根据index显示对应的分页视图
        // ...
    }
}