How to stop the QR reader ZbarScannerView, problem with stopCamera ()

Create an app ... qr selector with zbarscannerview is in a fragment specifically in a RelativeLayout, I already get the QR code, but it freezes when I get it .. with stopCamera () does not stop it .. help please urgently thanks .. So I start the camera by means of a zbarScannerr class () ...

btnEscanear.setOnClickListener(new View.OnClickListener() {
   @Override
   public void onClick(View v) {
   Toast.makeText(getContext(), "onclick",Toast.LENGTH_SHORT).show();
    vistaEscaner = new ZBarScannerView(getContext());
    vistaEscaner.setResultHandler(new zbarScannerr());
    RelativeLayout rl=vista.findViewById(R.id.idRlayoutQR);
    rl.addView(vistaEscaner);
    vistaEscaner.startCamera();
    } });
    return vista;
    }
public class zbarScannerr implements ZBarScannerView.ResultHandler {
@Override
public void handleResult(Result result) {
     vistaEscaner.stopCamera();
     //timbre();
 String dato=result.getContents();//obtenemos el codigoQR
}
}