前不久有网友跟我说，demo有bug不能运行，所以抽空改了一下，主要原因是swift版本问题，当初我写这个demo的时候是Swift3.0 贝塔版，所以有些语法上的更新。
在过去的WWDC2016中，Apple Inc推出了新版Swift--Swift3.0；对于Swift3.0的语法什么的，在此就不聊了，毕竟人家还是个小白。
Apple Inc WWDC2016
书归正传，iOS7.0以前要使用二维码扫描功能，需要借助两大开源的组件ZBar和ZXing来实现，自iOS7.0之后可以使用自带的AVFoundation框架实现二维码扫描，而且效率更高。
因此实现二维码扫描首先需要导入AVFoundation框架
- 1 导入AVFoundation框架
import AVFoundation
- 2 创建视图预览显示并设置想实现的UI效果
//屏幕扫描区域视图
//屏幕扫描区域视图
let barcodeView = UIView(frame: CGRect(x: UIScreen.main.bounds.size.width * 0.2, y: UIScreen.main.bounds.size.height * 0.35, width: UIScreen.main.bounds.size.width * 0.6, height: UIScreen.main.bounds.size.width * 0.6))
//扫描线
let scanLine = UIImageView()
var scanning : String!
var timer = Timer()
override init(frame: CGRect) {
super.init(frame: frame)
barcodeView.layer.borderWidth = 1.0
barcodeView.layer.borderColor = UIColor.white.cgColor
self.addSubview(barcodeView)
//设置扫描线
scanLine.frame = CGRect(x: 0, y: 0, width: barcodeView.frame.size.width, height: 5)
scanLine.image = UIImage(named: "QRCodeScanLine")
//添加扫描线图层
barcodeView.addSubview(scanLine)
self.createBackGroundView()
self.addObserver(self, forKeyPath: "scanning", options: .new, context: nil)
timer = Timer.scheduledTimer(timeInterval: 2, target: self, selector: #selector(moveScannerLayer(_:)), userInfo: nil, repeats: true)
}
- 3 实现背景灰色半透明，分四个View,设置所需要实现的样式；同样的也可以采用重写drawRect方法来实现。
func createBackGroundView() {
let topView = UIView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.size.width, height: UIScreen.main.bounds.size.height * 0.35))
let bottomView = UIView(frame: CGRect(x: 0, y: UIScreen.main.bounds.size.width * 0.6 + UIScreen.main.bounds.size.height * 0.35, width: UIScreen.main.bounds.size.width, height: UIScreen.main.bounds.size.height * 0.65 - UIScreen.main.bounds.size.width * 0.6))
let leftView = UIView(frame: CGRect(x: 0, y: UIScreen.main.bounds.size.height * 0.35, width: UIScreen.main.bounds.size.width * 0.2, height: UIScreen.main.bounds.size.width * 0.6))
let rightView = UIView(frame: CGRect(x: UIScreen.main.bounds.size.width * 0.8, y: UIScreen.main.bounds.size.height * 0.35, width: UIScreen.main.bounds.size.width * 0.2, height: UIScreen.main.bounds.size.width * 0.6))
topView.backgroundColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.4)
bottomView.backgroundColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.4)
leftView.backgroundColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.4)
rightView.backgroundColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.4)
let label = UILabel(frame: CGRect(x: 0, y: 10, width: UIScreen.main.bounds.size.width, height: 21))
label.textAlignment = .center
label.font = UIFont.systemFont(ofSize: 14)
label.textColor = UIColor.white
label.text = "将二维码/条形码放入扫描框内，即自动扫描"
bottomView.addSubview(label)
self.addSubview(topView)
self.addSubview(bottomView)
self.addSubview(leftView)
self.addSubview(rightView)
}
- 4 在初始化视图的时候添加观察者，用于实现暂停扫描时，扫描线停止滚动
self.addObserver(self, forKeyPath: "scanning", options: .new, context: nil)
override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
if scanning == "start" {
timer.fire()
}else{
timer.invalidate()
}
}
- 5 扫描线滚动动画
//让扫描线滚动
func moveScannerLayer(_ timer : Timer) {
scanLine.frame = CGRect(x: 0, y: 0, width: self.barcodeView.frame.size.width, height: 12)
UIView.animate(withDuration: 2) {
self.scanLine.frame = CGRect(x: self.scanLine.frame.origin.x, y: self.scanLine.frame.origin.y + self.barcodeView.frame.size.height - 10, width: self.scanLine.frame.size.width, height: self.scanLine.frame.size.height)
}
}
- 6 声明背景视图
//相机显示视图
let cameraView = ScannerBackgroundView(frame: UIScreen.main.bounds)
- 7 初始化捕捉设备、创建捕捉会话、输入媒体类型、设置代理等
let captureDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)
let input :AVCaptureDeviceInput
let output = AVCaptureMetadataOutput()
//捕捉异常,并处理异常
do{
input = try AVCaptureDeviceInput(device: captureDevice)
captureSession.addInput(input)
captureSession.addOutput(output)
}catch {
print("异常")
}
let dispatchQueue = DispatchQueue(label: "queue", attributes: [])
output.setMetadataObjectsDelegate(self, queue: dispatchQueue)
output.metadataObjectTypes = NSArray(array: [AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code,AVMetadataObjectTypeEAN8Code, AVMetadataObjectTypeCode128Code]) as [AnyObject]
let videoPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
videoPreviewLayer?.videoGravity = AVLayerVideoGravityResizeAspectFill
videoPreviewLayer?.frame = cameraView.bounds
cameraView.layer.insertSublayer(videoPreviewLayer!, at: 0)
output.rectOfInterest = CGRect(x: 0.2, y: 0.2, width: 0.6, height: 0.6)
- 8 扫描结果处理(根据不同扫描结果，执行不同的操作)
if metadataObjects != nil && metadataObjects.count > 0 {
let metaData : AVMetadataMachineReadableCodeObject = metadataObjects.first as! AVMetadataMachineReadableCodeObject
print(metaData.stringValue)
DispatchQueue.main.async(execute: {
let result = WebViewController()
result.url = metaData.stringValue
self.navigationController?.pushViewController(result, animated: true)
})
captureSession.stopRunning()
}
- 9 从相册中获取二维码图片进行识别，在此需要判断相册中获取的图片是否具有二维码信息
let image = info[UIImagePickerControllerOriginalImage]
let imageData = UIImagePNGRepresentation(image as! UIImage)
let ciImage = CIImage(data: imageData!)
let detector = CIDetector(ofType: CIDetectorTypeQRCode, context: nil, options: [CIDetectorAccuracy: CIDetectorAccuracyLow])
let array = detector?.features(in: ciImage!)
let result : CIQRCodeFeature = array!.first as! CIQRCodeFeature
let resultView = WebViewController()
resultView.url = result.messageString
self.navigationController?.pushViewController(resultView, animated: true)
picker.dismiss(animated: true, completion: nil)
欧了，所有工作都已完成；由于本人是个菜鸟，思路仅供参考，如果有更好的思路，欢迎交流。
附上：
demo地址：demo下载
