ok, there aren't any mistakes. You did some easy typo mistakes.
2) You still had project created with xcode3. That file created by you and then I modified for you. But I updated the library and method. I hardly suggest you to create new project and I did it for you below for download and it works charm. (works with the package installer of barcode library not previous one)
3) If you have problems, I will always help you and you can send me private messages. You put the file with error here and people downloading error file (I do not know why). This mislead others, so you can private message and email me in any issues.
One more thing; while testing, After you press scan button, be careful the cam is not viewing the qr code at that time. Get the alert, press ok, then scan the qr code. This only apply for running without license.