Barcode Scanner with Ionic 3 docs

[samever1]

Could you please have a look at this link? @rapropos?
Or anyone else can help?
I checked the doc and nothing there about this, and the error really confused me.

Why can't using BarcodeScanner inside a service?

As title, I got a runtime error: Can’t resolve all parameters for ScannerService: (?). codes : import { BarcodeScanner } from '@ionic-native/barcode-scanner'; export class ScannerService{ constructor( private barcodeScanner: BarcodeScanner ) { console.log('Hello ScannerService Provider'); } ... } If I remove private barcodescanner, it runs fine. Anyone can help?