无法创建新文件夹

Question

我正在创建一个图库应用程序。我已经在我的应用程序（在相应文件夹中）中显示了手机中的图像。我是通过获取哑剧Hash.new { |h, k| h[k] = h.dup.clear }的文件来完成此操作的。现在，我要添加“添加新文件夹”功能。我添加了一个加号按钮。因此，应创建新文件夹。它的工作，新文件夹正在创建。问题是当运行应用程序时，创建的新文件夹未显示。原因是新文件夹内没有文件。因此无法检查MIME类型。如何实现此功能？谁能帮我吗？

这是我创建文件夹的方式：

SELECT company_name AS company,
       DOMAIN,
       city_name AS city,
       state_province_code AS state,
       country_code AS country,
       location_revenue AS revenueRange,
       location_TI_industry AS industry,
       location_employeecount_range AS employeeSize,
       topic,
       location_duns AS duns,
       rank AS intensityRank,
       dnb_status_code AS locationStatus,
       rank_delta AS intensityRankDelta,
       company_id,
       ROW_NUMBER() OVER (PARTITION BY DOMAIN) AS rowNumberFROM company_intent c
 WHERE c.rank > 0
   AND c.rank <= 10
   AND c.signal_count > 0
   AND c.topic IN ('Cloud Computing')
   AND c.country_code = 'US'
   AND c.rank IN (7, 8, 9, 10)
 GROUP BY c.location_duns,
          company_name,
          DOMAIN,
          city_name,
          state_province_code,
          country_code,
          location_revenue,
          location_TI_industry,
          location_employeecount_range,
          topic,
          rank,
          dnb_status_code,
          rank_delta,
          company_id
 ORDER BY intensityRank DESC
 LIMIT 15 SELECT COUNT (DISTINCT c.company_id) AS COUNT
  FROM company_intent c
 WHERE c.rank > 0
   AND c.rank <= 10
   AND c.signal_count > 0
   AND c.topic IN ('Cloud Computing')
   AND c.country_code = 'US'
   AND c.rank IN (7, 8, 9, 10)