ios - 如何使用 swift 在 iOS 应用程序中生成 QR 图像

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您好，我正在开发一个 iOS 项目，我想生成自定义的二维码，但不知道该怎么做。我还附上了一个示例。

我想用 Swift 语言生成这样的二维码。谢谢

Answer 1

以下是生成中心带有 Logo 图像的二维码的代码:

import UIKit
import EventKit
import CoreImage

class ViewController: UIViewController {

@IBOutlet weak var imageView: UIImageView!

  override func viewDidLoad() {
    super.viewDidLoad()

    guard let qrURLImage = URL(string: "https://www.thepramodkumar.com/")?.qrImage(using: #colorLiteral(red: 0.3490196078, green: 0.768627451, blue: 0.6823529412, alpha: 1), logo: #imageLiteral(resourceName: "logo")) else { return }
    
    imageView.image = qrURLImage
    
   }
}


extension URL {

   /// Creates a QR code for the current URL in the given color.
   func qrImage(using color: UIColor, logo: UIImage? = nil) -> UIImage? {
    
      guard let tintedQRImage = qrImage?.tinted(using: color) else {
         return nil
      }
    
      guard let logo = logo?.cgImage else {
         return UIImage(ciImage: tintedQRImage)
      }
    
      guard let final = tintedQRImage.combined(with: CIImage(cgImage: logo)) else {
        return UIImage(ciImage: tintedQRImage)
      }
    
    return UIImage(ciImage: final)
  }

  /// Returns a black and white QR code for this URL.
  var qrImage: CIImage? {
    guard let qrFilter = CIFilter(name: "CIQRCodeGenerator") else { return nil }
    let qrData = absoluteString.data(using: String.Encoding.ascii)
    qrFilter.setValue(qrData, forKey: "inputMessage")
    
    let qrTransform = CGAffineTransform(scaleX: 12, y: 12)
    return qrFilter.outputImage?.transformed(by: qrTransform)
  }
}

extension CIImage {
  /// Inverts the colors and creates a transparent image by converting the mask to alpha.
  /// Input image should be black and white.
  var transparent: CIImage? {
     return inverted?.blackTransparent
  }

  /// Inverts the colors.
  var inverted: CIImage? {
      guard let invertedColorFilter = CIFilter(name: "CIColorInvert") else { return nil }
    
    invertedColorFilter.setValue(self, forKey: "inputImage")
    return invertedColorFilter.outputImage
  }

  /// Converts all black to transparent.
  var blackTransparent: CIImage? {
      guard let blackTransparentFilter = CIFilter(name: "CIMaskToAlpha") else { return nil }
    blackTransparentFilter.setValue(self, forKey: "inputImage")
    return blackTransparentFilter.outputImage
  }

  /// Applies the given color as a tint color.
  func tinted(using color: UIColor) -> CIImage? {
     guard
        let transparentQRImage = transparent,
        let filter = CIFilter(name: "CIMultiplyCompositing"),
        let colorFilter = CIFilter(name: "CIConstantColorGenerator") else { return nil }
    
    let ciColor = CIColor(color: color)
    colorFilter.setValue(ciColor, forKey: kCIInputColorKey)
    let colorImage = colorFilter.outputImage
    
    filter.setValue(colorImage, forKey: kCIInputImageKey)
    filter.setValue(transparentQRImage, forKey: kCIInputBackgroundImageKey)
    
    return filter.outputImage!
  }
}

extension CIImage {

  /// Combines the current image with the given image centered.
  func combined(with image: CIImage) -> CIImage? {
    guard let combinedFilter = CIFilter(name: "CISourceOverCompositing") else { return nil }
    let centerTransform = CGAffineTransform(translationX: extent.midX - (image.extent.size.width / 2), y: extent.midY - (image.extent.size.height / 2))
    combinedFilter.setValue(image.transformed(by: centerTransform), forKey: "inputImage")
    combinedFilter.setValue(self, forKey: "inputBackgroundImage")
    return combinedFilter.outputImage!
  }
}

Github 存储库: https://github.com/bestiosdeveloper/QACodeDemo