@Override
 protected Void doInBackground(String... params) {
   mFileSize.clear();
   mFileTime.clear();
   ArrayList<String> fileList = (ArrayList<String>) FileUtils.getVideoFileName();
   for (String str : fileList) {
     mFileSize.add(FileUtils.getFileSize(str));
     mFileTime.add(FileUtils.getVideoTime(getContentResolver(), getResources(), str));
   }
   mFileList = fileList;
   return null;
 }