QR Code reader & generator in Swift

Question

Currently in Objective-C, i use Zbar(http://zbar.sourceforge.net/) to generate & read QR Code. Now, i want to move on Swift development only, is there any 'how to' or library about generate and read QR Code in Swift ?

Answer 1

Beginning with iOS 7, iOS devices can read QR codes. However, there is no built-in way to generate a QR code. Here's a quick and dirty QR code reader.

First, import AVFoundation and add AVCaptureMetadataOutputObjectsDelegate

Next, setup the capture session:

func captureQRCode() {
    let session = AVCaptureSession()
    let device = AVCaptureDevice.defaultDeviceWithMediaType(AVMediaTypeVideo)

    let input = AVCaptureDeviceInput.deviceInputWithDevice(device, error: nil) as AVCaptureDeviceInput
    session.addInput(input)

    let output = AVCaptureMetadataOutput()
    output.setMetadataObjectsDelegate(self, queue: dispatch_get_main_queue())
    session.addOutput(output)
    output.metadataObjectTypes = [AVMetadataObjectTypeQRCode]

    let previewLayer = AVCaptureVideoPreviewLayer(session: session)
    let bounds = self.view.layer.bounds
    previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill
    previewLayer.bounds = bounds
    previewLayer.position = CGPointMake(CGRectGetMidX(bounds), CGRectGetMidY(bounds))

    self.view.layer.addSublayer(previewLayer)
    session.startRunning()
}

Finally, handle the delegate

func captureOutput(captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [AnyObject]!, fromConnection connection: AVCaptureConnection!) {
    for item in metadataObjects {
        if let metadataObject = item as? AVMetadataMachineReadableCodeObject {
            if metadataObject.type == AVMetadataObjectTypeQRCode {
                println("QR Code: \(metadataObject.stringValue)")
            }
        }
    }
}