swift 3.0 Xcode 8.1

需要在info.plist 添加 Privacy - Camera Usage Description YES

import UIKit
import AVFoundation
 
class ViewController: UIViewController,AVCaptureMetadataOutputObjectsDelegate {
   
    var session: AVCaptureSession!  //输入输出的中间桥梁
   
    var myInput: AVCaptureDeviceInput!  //创建输入流
    var myOutput: AVCaptureMetadataOutput!  //创建输出流
   
    var bgView = UIView()
    var barcodeView = UIView()
   
    var timer = Timer()
    var scanLine = UIImageView()
   
    override func viewDidLoad() {
        super.viewDidLoad()
       
        //设置定时器，延迟2秒启动
        self.timer = Timer.scheduledTimer(timeInterval: 2,target: self,selector: #selector(moveScannerLayer(_:)),userInfo: nil,repeats: true)
       
        //初始化链接对象
        self.session = AVCaptureSession.init()
        //设置高质量采集率
        self.session.canSetSessionPreset(AVCaptureSessionPresetHigh)
       
        //获取摄像设备
        let device: AVCaptureDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)
       
        //捕捉异常，并处理
        do {
            self.myInput = try AVCaptureDeviceInput.init(device: device)
            self.myOutput = AVCaptureMetadataOutput.init()
            self.session.addInput(self.myInput)
            self.session.addOutput(self.myOutput)
        } catch {
            print("error")
        }
       
        //创建预览视图
        self.createBackGroundView()
       
        //设置扫描范围(横屏)
        self.myOutput.rectOfInterest = CGRect(x: 0.35,y: 0.2,width: UIScreen.main.bounds.width * 0.6 / UIScreen.main.bounds.height,height: 0.6)
      
        //设置扫码支持的编码格式(如下设置条形码和二维码兼容)
        myOutput.MetadataObjectTypes = [AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code,AVMetadataObjectTypeEAN8Code,AVMetadataObjectTypeCode128Code]
       
        //创建串行队列
        let dispatchQueue = DispatchQueue(label: "queue",attributes: [])
        //设置输出流的代理
        self.myOutput.setMetadataObjectsDelegate(self,queue: dispatchQueue)
       
        //创建预览图层
        let myLayer = AVCaptureVideoPreviewLayer.init(session: self.session)
        myLayer?.videoGravity = AVLayerVideoGravityResizeAspectFill  //设置预览图层的填充方式
        myLayer?.frame = self.view.layer.bounds  //设置预览图层的frame
        self.bgView.layer.insertSublayer(myLayer!,at: 0)  //将预览图层(摄像头画面)插入到预览视图的最底部
       
        //开始扫描
        self.session.startRunning()
        self.timer.fire()
    }
   
   
    //扫描结果，代理
    func captureOutput(_ captureOutput: AVCaptureOutput!,didOutputMetadataObjects MetadataObjects: [Any]!,from connection: AVCaptureConnection!) {
       
        if MetadataObjects != nil && MetadataObjects.count > 0 {
           
            //停止扫描
            self.session.stopRunning()
            timer.invalidate()
           
            //获取第一个
            let MetaData = MetadataObjects.first as! AVMetadataMachineReadableCodeObject
            print(MetaData.stringValue)
           
            DispatchQueue.main.async(execute: {
                //扫描到之后的操作
                //......
                print(MetaData.stringValue)
            })
        }
    }
   
    //创建预览视图
    func createBackGroundView() {
       
        self.bgView.frame = UIScreen.main.bounds
        self.bgView.backgroundColor = UIColor.black
        self.view.addSubview(self.bgView)
       
        //灰色蒙版
        let topView = UIView(frame: CGRect(x: 0,y: 0,width: UIScreen.main.bounds.size.width,height: UIScreen.main.bounds.size.height * 0.35))
       
        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,height: UIScreen.main.bounds.size.width * 0.6))
       
        let bottomView = UIView(frame: CGRect(x: 0,y: UIScreen.main.bounds.size.width * 0.6 + UIScreen.main.bounds.size.height * 0.35,height: UIScreen.main.bounds.size.height * 0.65 - UIScreen.main.bounds.size.width * 0.6))
       
        topView.backgroundColor = UIColor(red: 0,green: 0,blue: 0,alpha: 0.4)
        bottomView.backgroundColor = UIColor(red: 0,alpha: 0.4)
        leftView.backgroundColor = UIColor(red: 0,alpha: 0.4)
        rightView.backgroundColor = UIColor(red: 0,alpha: 0.4)
       
        //文字说明
        let label = UILabel(frame: CGRect(x: 0,y: 10,height: 21))
        label.textAlignment = NSTextAlignment.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.bgView.addSubview(topView)
        self.bgView.addSubview(bottomView)
        self.bgView.addSubview(leftView)
        self.bgView.addSubview(rightView)
       
       
        //屏幕中间扫描区域视图（透明）
        barcodeView.frame = CGRect(x: UIScreen.main.bounds.size.width * 0.2,width: UIScreen.main.bounds.size.width * 0.6,height: UIScreen.main.bounds.size.width * 0.6)
        barcodeView.backgroundColor = UIColor.clear
        barcodeView.layer.borderWidth = 1.0
        barcodeView.layer.borderColor = UIColor.white.cgColor
        self.bgView.addSubview(barcodeView)
       
        //扫描线
        scanLine.frame = CGRect(x: 0,width: barcodeView.frame.size.width,height: 5)
        scanLine.image = UIImage(named: "QRCodeScanLine")
        barcodeView.addSubview(scanLine)
       
    }
   
    //扫描线滚动
    func moveScannerLayer(_ timer : Timer) {
        self.scanLine.frame = CGRect(x: 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)
        }
       
    }
 
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}