Rather than QRCODE ZXing library integration You are able to open camera and scan QRCode from anywhere:
The code i found below will may be helps to you for scanning QRCode :
try {
Intent intent = new Intent("com.google.zxing.client.android.SCAN");
intent.putExtra("SCAN_MODE", "QR_CODE_MODE"); // "PRODUCT_MODE for bar codes
startActivityForResult(intent, 0);
} catch (Exception e) {
Uri marketUri = Uri.parse("market://details?id=com.google.zxing.client.android");
Intent marketIntent = new Intent(Intent.ACTION_VIEW,marketUri);
startActivity(marketIntent);
}
Please remember that You must have a barcode scanner application by "Zxing" in Mobile Phone else it will firstly redirect to Google play store link for download it.