swift UIImageExtension

UIImageExtension.swift

// MARK: 颜色转UIImage
extension UIImage {
    
    public convenience init?(color: UIColor, size: CGSize = CGSize(width: 1.0, height: 1.0)) {
        UIGraphicsBeginImageContextWithOptions(size, true, UIScreen.main.scale)
        defer {
            UIGraphicsEndImageContext()
        }
        let context = UIGraphicsGetCurrentContext()
        context?.setFillColor(color.cgColor)
        context?.fill(CGRect(origin: CGPoint.zero, size: size))
        context?.setShouldAntialias(true)
        let image = UIGraphicsGetImageFromCurrentImageContext()
        guard let cgImage = image?.cgImage else {
            self.init()
            return nil
        }
        self.init(cgImage: cgImage)
    }
    
}

// MARK: 图片设置圆角
extension UIImage {
    
    public func roundImage(byRoundingCorners: UIRectCorner = UIRectCorner.allCorners, cornerRadi: CGFloat) -> UIImage? {
        return roundImage(byRoundingCorners: byRoundingCorners, cornerRadii: CGSize(width: cornerRadi, height: cornerRadi))
    }
    
    public func roundImage(byRoundingCorners: UIRectCorner = UIRectCorner.allCorners, cornerRadii: CGSize) -> UIImage? {
        
        let imageRect = CGRect(origin: CGPoint.zero, size: size)
        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        defer {
            UIGraphicsEndImageContext()
        }
        let context = UIGraphicsGetCurrentContext()
        guard context != nil else {
            return nil
        }
        context?.setShouldAntialias(true)
        let bezierPath = UIBezierPath(roundedRect: imageRect,
                                      byRoundingCorners: byRoundingCorners,
                                      cornerRadii: cornerRadii)
        bezierPath.close()
        bezierPath.addClip()
        self.draw(in: imageRect)
        return UIGraphicsGetImageFromCurrentImageContext()
    }
}

// MARK: 通过String生成二维码
extension UIImage {
    
    public static func generateQRImage(QRCodeString: String, logo: UIImage?, size: CGSize = CGSize(width: 50, height: 50)) -> UIImage? {
        guard let data = QRCodeString.data(using: .utf8, allowLossyConversion: false) else {
            return nil
        }
        let imageFilter = CIFilter(name: "CIQRCodeGenerator")
        imageFilter?.setValue(data, forKey: "inputMessage")
        imageFilter?.setValue("H", forKey: "inputCorrectionLevel")
        let ciImage = imageFilter?.outputImage
        
        // 创建颜色滤镜
        let colorFilter = CIFilter(name: "CIFalseColor")
        colorFilter?.setDefaults()
        colorFilter?.setValue(ciImage, forKey: "inputImage")
        colorFilter?.setValue(CIColor(red: 0, green: 0, blue: 0), forKey: "inputColor0")
        colorFilter?.setValue(CIColor(red: 1, green: 1, blue: 1), forKey: "inputColor1")
        
        // 返回二维码图片
        let qrImage = UIImage(ciImage: (colorFilter?.outputImage)!)
        let imageRect = size.width > size.height ?
            CGRect(x: (size.width - size.height) / 2, y: 0, width: size.height, height: size.height) :
            CGRect(x: 0, y: (size.height - size.width) / 2, width: size.width, height: size.width)
        UIGraphicsBeginImageContextWithOptions(imageRect.size, false, UIScreen.main.scale)
        defer {
            UIGraphicsEndImageContext()
        }
        qrImage.draw(in: imageRect)
        if logo != nil {
            let logoSize = size.width > size.height ?
                CGSize(width: size.height * 0.25, height: size.height * 0.25) :
                CGSize(width: size.width * 0.25, height: size.width * 0.25)
            logo?.draw(in: CGRect(x: (imageRect.size.width - logoSize.width) / 2, y: (imageRect.size.height - logoSize.height) / 2, width: logoSize.width, height: logoSize.height))
        }
        return UIGraphicsGetImageFromCurrentImageContext()
    }
    
}