swift 3 asking permission while using camera

Question

I have read many of articles regarding on this issues that only adds lines of code on plist like:

Key     :  Privacy - Camera Usage Description   
Value   :  $(PRODUCT_NAME) camera use

but i still got the same issue that

ERROR MESSAGE

'Attempted to start scanning on a device with no camera. Check requestCameraPermissionWithSuccess: method before calling startScanningWithResultBlock:'

It seems like it still do not have the permission on using the camera on the apps

but then actually how are we going to gain camera access on iOS device?

and this are my code

    MTBBarcodeScanner.requestCameraPermission(success: { success in
        if success {
            do {
                try self.scanner?.startScanning(resultBlock: { codes in
                    if let codes = codes {
                        for code in codes {
                            let stringValue = code.stringValue!
                            print("Found code: \(stringValue)")

                            if (stringValue != nil)
                            { ... }

                                    })
                                }))
                                self.present(alert, animated: true, completion: nil)
                            }
                        }
                    }
                })
            } catch {
                NSLog("Unable to start scanning")
            }
        } else {
            UIAlertView(title: "Scanning Unavailable", message: "This app does not have permission to access the camera", delegate: nil, cancelButtonTitle: nil, otherButtonTitles: "Ok").show()
        }
    })

Answer 1

in order to get access to the devices' camera you have to provide a Camera Usage Description. You do this in your Info.plist file.

Simply click the "+" icon next to where it says "Information Property List" and type Privacy - Camera Usage Description . Then as a value provide a short usage info, for example "We need access in order to scan barcodes."

Hope this helps.