How can I generate a barcode from a string in Swift?

Question

I am a new iOS developer. I was wondering how can I generate a barcode in Swift.

I have the code already, there are multiple resources from where to learn how to read a barcode, but I didn't find any that talks about generating one from a string.

Thanks a lot!

P.S. I know there is a similar question about this, but it's for Objective-C. I don't know Obj-C and I find it difficult coming from .NET.

Answer 1

You could use a CoreImage (import CoreImage) filter to do that!

    class Barcode {         class func fromString(string : String) -> UIImage? {              let data = string.data(using: .ascii)              if let filter = CIFilter(name: "CICode128BarcodeGenerator") {                   filter.setValue(data, forKey: "inputMessage")                   if let outputCIImage = filter.outputImage {                        return UIImage(ciImage: outputCIImage)                   }              }              return nil         }     }      let img = Barcode.fromString("whateva") 

A newer version, with guard and failable initialiser:

extension UIImage {      convenience init?(barcode: String) {         let data = barcode.data(using: .ascii)         guard let filter = CIFilter(name: "CICode128BarcodeGenerator") else {             return nil         }         filter.setValue(data, forKey: "inputMessage")         guard let ciImage = filter.outputImage else {             return nil         }         self.init(ciImage: ciImage)     }  } 

Usage:

let barcode = UIImage(barcode: "some text") // yields UIImage? 

According to the docs :

Generates an output image representing the input data according to the ISO/IEC 15417:2007 standard. The width of each module (vertical line) of the barcode in the output image is one pixel. The height of the barcode is 32 pixels. To create a barcode from a string or URL, convert it to an NSData object using the NSASCIIStringEncoding string encoding.