I'm trying to make a barcode scanner where they read the barcode number and if it in the list it produce a specific comment

I need help with the bar code scanner to scan a product, but every time i try to used it, it say error. i tried to used zyxing scanview one also but it didnt manage to read the barcode

There are lots of errors to choose from.

Which was yours?

Show us the blocks and the aia