尝试使用onSaveInstanceState()恢复String[][]时出现"java.lang.NullPointerException:尝试获取空数组的长度“

@Override
protected void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    // 保存String[][]数据
    if (stringArray != null) {
        Parcelable[] parcelableArray = new Parcelable[stringArray.length];
        for (int i = 0; i < stringArray.length; i++) {
            parcelableArray[i] = stringArray[i];
        }
        outState.putParcelableArray("stringArray", parcelableArray);
    }
}

@Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
    super.onRestoreInstanceState(savedInstanceState);
    // 恢复String[][]数据
    Parcelable[] parcelableArray = savedInstanceState.getParcelableArray("stringArray");
    if (parcelableArray != null) {
        stringArray = new String[parcelableArray.length][];
        for (int i = 0; i < parcelableArray.length; i++) {
            stringArray[i] = (String[]) parcelableArray[i];
        }
    }
}