代碼如下：
import UIKit
import AVFoundation
import WebKit
class ViewController: UIViewController,AVCaptureMetadataOutputObjectsDelegate {
var session:AVCaptureSession!
var screenWidth : CGFloat!
var screenHeight:CGFloat!
override func viewDidLoad() {
super.viewDidLoad()
screenWidth = self.view.bounds.width
screenHeight = self.view.bounds.height
setView()
setCamera()
}
//設置除了掃描區以外的視圖
func setView(){
let leftView = UIView(frame: CGRect(x: 0, y: 0, width: screenWidth/2-100, height: screenHeight))
leftView.backgroundColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.6)
self.view.addSubview(leftView)
let rightView = UIView(frame: CGRect(x: screenWidth/2+100, y: 0, width: screenWidth-(screenWidth/2+100), height: screenHeight))
rightView.backgroundColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.6)
self.view.addSubview(rightView)
let topView = UIView(frame: CGRect(x: screenWidth/2-100, y: 0, width: 200, height: 100))
topView.backgroundColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.6)
self.view.addSubview(topView)
let bottomView = UIView(frame: CGRect(x: screenWidth/2-100, y: 300, width: 200, height: screenHeight-300))
bottomView.backgroundColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.6)
self.view.addSubview(bottomView)
}
//設置相機
func setCamera(){
//獲取攝像設備
guard let device = AVCaptureDevice.default(for: AVMediaType.video) else {
return
}
do {
//創建輸入流
let input = try AVCaptureDeviceInput(device: device)
//創建輸出流
let output = AVCaptureMetadataOutput()
//設置會話
session = AVCaptureSession()
//連接輸入輸出
if session.canAddInput(input){
session.addInput(input)
}
if session.canAddOutput(output){
session.addOutput(output)
//設置輸出流代理，從接收端收到的所有元數據都會被傳送到delegate方法，所有delegate方法均在queue中執行
output.setMetadataObjectsDelegate(self, queue: DispatchQueue.main)
//設置掃描二維碼類型
output.metadataObjectTypes = [ AVMetadataObject.ObjectType.qr]
//掃描區域
//rectOfInterest 屬性中x和y互換，width和height互換。
output.rectOfInterest = CGRect(x: 100/screenHeight, y: (screenWidth/2-100)/screenWidth, width: 200/screenHeight, height: 200/screenWidth)
}
//捕捉圖層
let previewLayer = AVCaptureVideoPreviewLayer(session: session)
previewLayer.videoGravity = .resizeAspectFill
previewLayer.frame = self.view.layer.bounds
self.view.layer.insertSublayer(previewLayer, at: 0)
//持續對焦
if device.isFocusModeSupported(.continuousAutoFocus){
try input.device.lockForConfiguration()
input.device.focusMode = .continuousAutoFocus
input.device.unlockForConfiguration()
}
session.startRunning()
} catch {
}
}
//掃描完成的代理
func metadataOutput(_ output: AVCaptureMetadataOutput, didOutput metadataObjects: [AVMetadataObject], from connection: AVCaptureConnection) {
session?.stopRunning()
if let metadataObject = metadataObjects.first {
let readableObject = metadataObject as! AVMetadataMachineReadableCodeObject
let str = readableObject.stringValue!
let url = URL(string: str)
//用網頁打開掃描的信息
if #available(iOS 10, *){
UIApplication.shared.open(url!, options: [:], completionHandler: nil)
}else{
UIApplication.shared.openURL(url!)
}
}
}
}