qrGen.java

private void qrGeneration(String qrText) {
        QRCodeWriter writer = new QRCodeWriter();
        try {
            BitMatrix bitMatrix = writer.encode(qrText, BarcodeFormat.QR_CODE, 564, 564);
            int width = bitMatrix.getWidth();
            int height = bitMatrix.getHeight();
            Bitmap bmp = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565);
            for (int x = 0; x < width; x++) {
                for (int y = 0; y < height; y++) {
                    bmp.setPixel(x, y, bitMatrix.get(x, y) ? Color.BLACK : Color.WHITE);
                }
            }
            bitmap = bmp;
            ((ImageView) findViewById(R.id.qrImage)).setImageBitmap(bmp);

        } catch (WriterException e) {
            e.printStackTrace();
        }
    }
// Just set the bitmap to any imageView you want it to show.