android onScanCompleted fails

Question

My code:

    public class MarkersActivity extends Activity implements MediaScannerConnectionClient{

    public String[] allFiles;
    private String SCAN_PATH ;
    private String PACKAGE_NAME = "testing"
    private static final String FILE_TYPE = "image/*";
    private MediaScannerConnection conn;
    ...
        public void iconPhoto_Click(View v) {
            File directory = new File(Environment.getExternalStorageDirectory() + File.separator + PACKAGE_NAME + File.separator + String.valueOf(selectedID));
            String directory_string = Environment.getExternalStorageDirectory() + File.separator + PACKAGE_NAME + File.separator + String.valueOf(selectedID); 

            if (directory.exists()){
                allFiles = directory.list();
                SCAN_PATH = directory_string + File.separator + allFiles[0];
                startScan();
            }
        }
...
    private void startScan()
    {
        if(conn!=null){
            conn.disconnect();
        }
        conn = new MediaScannerConnection(this, this);
        conn.connect();
    }

    @Override
    public void onMediaScannerConnected()
    {
        conn.scanFile(SCAN_PATH, FILE_TYPE);    
    }

    @Override
    public void onScanCompleted(String path, Uri uri)
    {
        Log.d("!!!!!!!!!!!!!", "onScanCompleted");
        try{
            if (uri != null){
                Intent intent = new Intent(Intent.ACTION_VIEW);
                intent.setData(uri);
                startActivity(intent);
            }
        }finally{
            conn.disconnect();
            conn = null;
        }
    }   

onScanCompleted - not running

Log.d("!!!!!!!!!!!!!", "onScanCompleted"); - not running

I would like that when you click on the button displays the photos in the gallery of my folders. Code found in the answers to this site, but it does not work.

I ask you to tell me where the error.

Help me pls... Thank you!