Get images thumbnail file paths

问题:

I'm trying to get the thumnail paths, not the bitmaps objects.
When I query for these, some of the thumbnail paths are null for some reason. (I have 1028 thumbnail images in my device, the cursor length is indeed 1028, but still returning nulls) I know there are 1028 thumbnail images because I checked. Here's my code:

     String[] projection = {MediaStore.Images.Thumbnails._ID};
  // Create the cursor pointing to the SDCard

  cursor = this.getContentResolver().query( MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI,
          projection, // Which columns to return
          null,       // Return all rows
          null,
          MediaStore.Images.Thumbnails.IMAGE_ID);
  // Get the column index of the Thumbnails Image ID
  Log.d(Global.TAG, "BEFORE");
  columnIndex = cursor.getColumnIndex(MediaStore.Images.Thumbnails._ID);
  Log.d(Global.TAG, "AFTER1");
  for(int i =0;i<cursor.getCount();i++){
      cursor.moveToPosition(i);

      Log.d("MyTag","BBABA" + i +" : " + getThumbnailPathForLocalFile(cursor.getLong(columnIndex)));
  }
  cursor.close();

My getThumbnailPathForLocalFile:

    String getThumbnailPathForLocalFile(long fileId)
 {
    // Log.d(Global., msg)
     Cursor thumbCursor = null;
     try
     {
         thumbCursor = this.getContentResolver().
                 query(MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI
                 , null
                 , MediaStore.Images.Thumbnails.IMAGE_ID + " = " + fileId+ " AND "
                   + MediaStore.Images.Thumbnails.KIND + " = "
                   + MediaStore.Images.Thumbnails.MINI_KIND , null, null);

         if(thumbCursor.moveToFirst())
         {
             // the path is stored in the DATA column
             int dataIndex = thumbCursor.getColumnIndexOrThrow( MediaStore.MediaColumns.DATA );
             String thumbnailPath = thumbCursor.getString(dataIndex);
             return thumbnailPath;
         }
     }
     finally
     {
         if(thumbCursor != null)
         {
             thumbCursor.close();
         }
     }

     return null;
 }

Here's my logcat: http://pastebin.com/UZLZF9Pg

After checking, I see that the ids I send are just like the index of the for loop. I'm not even sure that my code is supposed to work, so any other code will be great.

回答1:

You should query for MediaStore.Images.Thumbnails.DATA. To modify your example, it would look like this.

String[] projection = {MediaStore.Images.Thumbnails.DATA};
// Create the cursor pointing to the SDCard

    Cursor cursor = this.getContentResolver().query( MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI,
        projection, // Which columns to return
        null,       // Return all rows
        null,
        null);
// Get the column index of the Thumbnails Image ID
Log.d(TAG, "BEFORE");
int columnIndex = cursor.getColumnIndex(MediaStore.Images.Thumbnails.DATA);
Log.d(TAG, "AFTER1");
for(int i =0;i<cursor.getCount();i++){
    cursor.moveToPosition(i);

    Log.d("MyTag","BBABA" + i +" : " + cursor.getString(columnIndex));
}
cursor.close();

Reference: How to get imagepath from thumbnail path of a image?