Question

截至目前，我的qr代码扫描程序只能扫描到网址，我怎样才能触发从qrscannercontroller到另一个uiviewcontroller的segue推送？我的朋友已经使用qr代码静态文本使用android studio。

这是我的qrscannercontroller.swift

import UIKit
import AVFoundation

class QRScannerController: UIViewController, AVCaptureMetadataOutputObjectsDelegate {

    @IBOutlet var messageLabel:UILabel!
    @IBOutlet var topbar: UIView!

    var captureSession:AVCaptureSession?
    var videoPreviewLayer:AVCaptureVideoPreviewLayer?
    var qrCodeFrameView:UIView?

    let supportedCodeTypes = [AVMetadataObjectTypeUPCECode,
                        AVMetadataObjectTypeCode39Code,
                        AVMetadataObjectTypeCode39Mod43Code,
                        AVMetadataObjectTypeCode93Code,
                        AVMetadataObjectTypeCode128Code,
                        AVMetadataObjectTypeEAN8Code,
                        AVMetadataObjectTypeEAN13Code,
                        AVMetadataObjectTypeAztecCode,
                        AVMetadataObjectTypePDF417Code,
                        AVMetadataObjectTypeQRCode]

    override func viewDidLoad() {
        super.viewDidLoad()

        // Get an instance of the AVCaptureDevice class to initialize a device object and provide the video as the media type parameter.
        let captureDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)

        do {
            // Get an instance of the AVCaptureDeviceInput class using the previous device object.
            let input = try AVCaptureDeviceInput(device: captureDevice)

            // Initialize the captureSession object.
            captureSession = AVCaptureSession()

            // Set the input device on the capture session.
            captureSession?.addInput(input)

            // Initialize a AVCaptureMetadataOutput object and set it as the output device to the capture session.
            let captureMetadataOutput = AVCaptureMetadataOutput()
            captureSession?.addOutput(captureMetadataOutput)

            // Set delegate and use the default dispatch queue to execute the call back
            captureMetadataOutput.setMetadataObjectsDelegate(self, queue: DispatchQueue.main)
            captureMetadataOutput.metadataObjectTypes = supportedCodeTypes

            // Initialize the video preview layer and add it as a sublayer to the viewPreview view's layer.
            videoPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
            videoPreviewLayer?.videoGravity = AVLayerVideoGravityResizeAspectFill
            videoPreviewLayer?.frame = view.layer.bounds
            view.layer.addSublayer(videoPreviewLayer!)

            // Start video capture.
            captureSession?.startRunning()

            // Move the message label and top bar to the front
            view.bringSubview(toFront: messageLabel)
            view.bringSubview(toFront: topbar)

            // Initialize QR Code Frame to highlight the QR code
            qrCodeFrameView = UIView()

            if let qrCodeFrameView = qrCodeFrameView {
                qrCodeFrameView.layer.borderColor = UIColor.green.cgColor
                qrCodeFrameView.layer.borderWidth = 2
                view.addSubview(qrCodeFrameView)
                view.bringSubview(toFront: qrCodeFrameView)
            }

        } catch {
            // If any error occurs, simply print it out and don't continue any more.
            print(error)
            return
        }
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


    // MARK: - AVCaptureMetadataOutputObjectsDelegate Methods

    func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [Any]!, from connection: AVCaptureConnection!) {

        // Check if the metadataObjects array is not nil and it contains at least one object.
        if metadataObjects == nil || metadataObjects.count == 0 {
            qrCodeFrameView?.frame = CGRect.zero
            messageLabel.text = "No QR/barcode is detected"
            return
        }

        // Get the metadata object.
        let metadataObj = metadataObjects[0] as! AVMetadataMachineReadableCodeObject

        if supportedCodeTypes.contains(metadataObj.type) {
            // If the found metadata is equal to the QR code metadata then update the status label's text and set the bounds
            let barCodeObject = videoPreviewLayer?.transformedMetadataObject(for: metadataObj)
            qrCodeFrameView?.frame = barCodeObject!.bounds

            if metadataObj.stringValue != nil {
                let url = URL(string: metadataObj.stringValue)!
                if #available(iOS 10.0, *) {
                    UIApplication.shared.open(url, options: [:], completionHandler: nil)
                } else {
                    UIApplication.shared.openURL(url)
                }
            }
        }
    }

}

这是我的uiviewcontroller

import UIKit    
class Quiz1Controller: UIViewController {    
    override func viewDidLoad() {
        super.viewDidLoad()    
        // Do any additional setup after loading the view.
    }
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
}

Answer 1

if supportedCodeTypes.contains(metadataObj.type) {
            // If the found metadata is equal to the QR code metadata then update the status label's text and set the bounds
            let barCodeObject = videoPreviewLayer?.transformedMetadataObject(for: metadataObj)
            qrCodeFrameView?.frame = barCodeObject!.bounds

      //Here you can implement the code to push viewController

        }
    }

您可以在从storyBoard连接segue后使用performSegue(withIdentifier: yourId, sender: nil)，也可以使用

self.navigationController?.pushViewController(yourNextViewController, animated: true)

Answer 2

你必须检查，天气url可以打开。如果您扫描了url，它将在浏览器中打开。如果它不是url，那么您可以根据您的逻辑处理操作。

不要强行打开URL值。它返回optional value。因此，请使用if let确保值不是nil

if let url = URL(string: metadataObj.stringValue) {
       if UIApplication.shared.canOpenURL(url) {
            if #available(iOS 10.0, *) {
                UIApplication.shared.open(url, options: [:], completionHandler: nil)
             } else {
                UIApplication.shared.openURL(url)
             }
        } else {
            //Logic to choose view controller identifier
            performSegue(withIdentifier: "quiz1VC segue id", sender: self)
        }
 }

更新：

问题：“多次执行QRCode扫描完成块”

解决方案：

if let _ = metadataObj.stringValue { 
   captureSession?.stopRunning() // Stop session before perform segue.
   self.performSegueWithIdentifier("abc", sender: self) 
}

使用qr代码扫描器（Xcode / Swift）将segue触发到另一个视图控制器

2 个答案: