title: Folder added on Android is not visible via USB
body: <p>I'm trying to save pictures in a subfolder on Android. Here's a bit of my code:</p>
  
  <pre><code>File path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM);
  path = new File(path, "SubDirName");
  path.mkdirs();
  </code></pre>
  
  <p>(I've tried <code>getExternalStorageDirectory</code> instead of <code>getExternalStoragePublicDirectory</code> and the Pictures folder instead of DCIM.)</p>
  
  <p>Any subfolder I add, including its contents, don't show up in Windows Explorer when the device is connected via USB. It does show in the Android File Manager, though.</p>
  
  <p>I've tried broadcasting the <code>ACTION_MEDIA_MOUNTED</code> intent on the new directory's parent. It didn't work.</p>
  
  <p>If I add a file in Windows, it shows up on Android. If I add a file on Android via the File Manager, it shows up in Windows. If I add the file programmatically, it shows up on the Android File Manager, but not in Windows Explorer. And I <em>need</em> to get it from Windows, and I don't want the final user to have to create the folder manually.</p>
  
  <p>What am I doing wrong?</p>