系统提供的AVCaptureSession仅仅适用于iOS7.0以上的系统。之前的请用Zbar来替代
下载地址：http://download.csdn.net/detail/huobanbengkui/8881097
配置project：
引入：
import Foundation
import AVFoundation
接受AVCaptureMetadataOutputObjectsDelegate（如： class QrcodeVC: UIViewController,AVCaptureMetadataOutputObjectsDelegate, UIAlertViewDelegate）
定义属性：
let device = AVCaptureDevice.defaultDeviceWithMediaType(AVMediaTypeVideo)
let session = AVCaptureSession()
var layer: AVCaptureVideoPreviewLayer?
一. 二维码扫描
1.使用相机捕捉二维码
func setupCamera(){
self.session.sessionPreset = AVCaptureSessionPresetHigh
var error : NSError?
let input = AVCaptureDeviceInput(device: device, error: &error)
if (error != nil && input == nil) {
var errorAlert = UIAlertView(title: "提醒", message: "请在iPhone的\"设置-隐私-相机\"选项中,同意本程序訪问您的相机", delegate: self, cancelButtonTitle: "确定")
errorAlert.show()
return
}
if session.canAddInput(input) {
session.addInput(input)
}
layer = AVCaptureVideoPreviewLayer(session: session)
layer!.videoGravity = AVLayerVideoGravityResizeAspectFill
//能够看到的镜头区域
layer!.frame = CGRectMake(0, 0,320,568)
self.view.layer.insertSublayer(self.layer, atIndex: 0)
let output = AVCaptureMetadataOutput()
//设置响应区域
// output.rectOfInterest = CGRectMake(0, 0, 0, 0)
output.setMetadataObjectsDelegate(self, queue: dispatch_get_main_queue())
if session.canAddOutput(output) {
session.addOutput(output)
output.metadataObjectTypes = [AVMetadataObjectTypeQRCode];
}
session.startRunning()
}
2.识别二维码以后，解析数据（实现AVCaptureMetadataOutputObjectsDelegate的代理方法）
func captureOutput(captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [AnyObject]!, fromConnection connection: AVCaptureConnection!) {
var stringValue:String?
if metadataObjects.count > 0 {
var metadataObject = metadataObjects[0] as!AVMetadataMachineReadableCodeObject
stringValue = metadataObject.stringValue
if stringValue != nil{
self.session.stopRunning()
}
}
self.session.stopRunning()
var alertView = UIAlertView(title: "二维码", message: stringValue, delegate: self, cancelButtonTitle: "确定")
alertView.show()
}
最后在页面消失的时候：
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(animated)
if self.session.running {
self.session.stopRunning()
}
}
二. 二维码生成
func createQRForString(qrString: String?, qrImageName: String?) -> UIImage?{
if let sureQRString = qrString {
let stringData = sureQRString.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)
// 创建一个二维码的滤镜
let qrFilter = CIFilter(name: "CIQRCodeGenerator")
qrFilter.setValue(stringData, forKey: "inputMessage")
qrFilter.setValue("H", forKey: "inputCorrectionLevel")
let qrCIImage = qrFilter.outputImage
// 创建一个颜色滤镜,黑白色
let colorFilter = CIFilter(name: "CIFalseColor")
colorFilter.setDefaults()
colorFilter.setValue(qrCIImage, 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image
let codeImage = UIImage(CIImage: colorFilter.outputImage.imageByApplyingTransform(CGAffineTransformMakeScale(5, 5)))
// 通常,二维码都是定制的,中间都会放想要表达意思的图片
if let iconImage = UIImage(named: qrImageName!) {
let rect = CGRectMake(0, 0, codeImage!.size.width, codeImage!.size.height)
UIGraphicsBeginImageContext(rect.size)
codeImage!.drawInRect(rect)
let avatarSize = CGSizeMake(rect.size.width * 0.25, rect.size.height * 0.25)
let x = (rect.width - avatarSize.width) * 0.5
let y = (rect.height - avatarSize.height) * 0.5
iconImage.drawInRect(CGRectMake(x, y, avatarSize.width, avatarSize.height))
let resultImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return resultImage
}
return codeImage
}
return nil
}
怎样使用呢？？
var imageViewIcon = UIImageView(frame: CGRectMake(100, 100, 150, 150))
imageViewIcon.image = createQRForString("好好", qrImageName: "ocrBack") //“ocrBack” 放入二维码中间图片的名字
self.view.addSubview(imageViewIcon)
如图：
最后说明：
AVFoundation框架不仅支持二维码扫描。还支持非常多别的条码类别。比如Code39，Code128，Aztec，和PDF417。大家能够尝试改动。