Is there a way to generate QR code image on iOS

Since iOS 7, you can use a Core Image filter to generate QR images. See the final tip here:

- (CIImage *)createQRForString:(NSString *)qrString {    NSData *stringData = [qrString dataUsingEncoding: NSISOLatin1StringEncoding];    CIFilter *qrFilter = [CIFilter filterWithName:@"CIQRCodeGenerator"];    [qrFilter setValue:stringData forKey:@"inputMessage"];    return qrFilter.outputImage;}

For Obj-C version that perfectly works for me, I've mixed answers पवन and Teja Kumar Bethina:

NSString *qrString = @"My string to encode";NSData *stringData = [qrString dataUsingEncoding: NSUTF8StringEncoding];CIFilter *qrFilter = [CIFilter filterWithName:@"CIQRCodeGenerator"];[qrFilter setValue:stringData forKey:@"inputMessage"];[qrFilter setValue:@"H" forKey:@"inputCorrectionLevel"];CIImage *qrImage = qrFilter.outputImage;float scaleX = self.qrImageView.frame.size.width / qrImage.extent.size.width;float scaleY = self.qrImageView.frame.size.height / qrImage.extent.size.height;qrImage = [qrImage imageByApplyingTransform:CGAffineTransformMakeScale(scaleX, scaleY)];self.qrImageView.image = [UIImage imageWithCIImage:qrImage                                             scale:[UIScreen mainScreen].scale                                       orientation:UIImageOrientationUp];

Using Swift 2

import UIKitimport CoreImagefunc createQRFromString(str: String) -> CIImage? {    let stringData = str.dataUsingEncoding(NSUTF8StringEncoding)        let filter = CIFilter(name: "CIQRCodeGenerator")        filter?.setValue(stringData, forKey: "inputMessage")        filter?.setValue("H", forKey: "inputCorrectionLevel")        return filter?.outputImage}if let img = createQRFromString("Hello world program created by someone") {    let somImage = UIImage(CIImage: img, scale: 1.0, orientation: UIImageOrientation.Down)}

Swift 3.0

import UIKitimport CoreImagefunc createQRFromString(_ str: String) -> CIImage? {        let stringData = str.data(using: String.Encoding.utf8)                let filter = CIFilter(name: "CIQRCodeGenerator")                filter?.setValue(stringData, forKey: "inputMessage")                filter?.setValue("H", forKey: "inputCorrectionLevel")                if let img = createQRFromString("Hello world program created by someone") {            let somImage = UIImage(ciImage: img, scale: 1.0, orientation: UIImageOrientation.down)        }                return filter?.outputImage    }if let img = createQRFromString("Hello world program created by someone") {            let somImage = UIImage(ciImage: img, scale: 1.0, orientation: UIImageOrientation.down)        }

Swift 4.2

private func createQRFromString(str: String) -> CIImage? {        let stringData = str.data(using: .utf8)                let filter = CIFilter(name: "CIQRCodeGenerator")        filter?.setValue(stringData, forKey: "inputMessage")        filter?.setValue("H", forKey: "inputCorrectionLevel")                return filter?.outputImage    }        var qrCode: UIImage? {        if let img = createQRFromString(str: "Hello world program created by someone") {            let someImage = UIImage(                ciImage: img,                scale: 1.0,                orientation: UIImage.Orientation.down            )            return someImage        }                return nil    }

Xcode 12.4 or Swift version >= 5.2

import UIKitimport CoreImagefunc createQRFromString(str: String) -> CIImage? {  let stringData = str.data(using: .utf8)    let filter = CIFilter(name: "CIQRCodeGenerator")    filter?.setValue(stringData, forKey: "inputMessage")    filter?.setValue("H", forKey: "inputCorrectionLevel")    return filter?.outputImage}if let img = createQRFromString(str: "Hello world program created by someone") {  let somImage = UIImage(ciImage: img, scale: 1.0, orientation: .down)}