How do you implement sharing with ReplayKit?

I am trying to use ReplayKit to record my app, and then give the user the option to share or delete the recording. The deleting works fine, but I can't get the sharing part to work properly. I've tried to use RPPreviewViewControllerMode with .shared, but XCode doesn't recognize it. I've also tried UIActivityViewController, which does pop-up the sharing menu - however, it doesn't work if I try to access the recording. Lastly, I tried previewControllerDelegate which allows the user to edit and save the video, but not share it.

I've posted my code below. Please advise, thank you!

import UIKit
import ReplayKit



class ViewController: UIViewController, RPPreviewViewControllerDelegate {


@IBOutlet weak var statusLabel: UILabel!

@IBOutlet weak var imagePicker: UISegmentedControl!
@IBOutlet weak var selectedImageView: UIImageView!
@IBOutlet weak var micToggle: UISwitch!
@IBOutlet weak var recordButton: UIButton!

var recorder = RPScreenRecorder.shared()

private var isRecording = false

@IBAction func imagePicked(_ sender: UISegmentedControl) {
    switch sender.selectedSegmentIndex {
    case 0:
        selectedImageView.image = UIImage(named: "skate")
    case 1:
        selectedImageView.image = UIImage(named: "food")
    case 2:
        selectedImageView.image = UIImage(named: "cat")
    case 3:
        selectedImageView.image = UIImage(named: "nature")
    default:
        selectedImageView.image = UIImage(named: "skate")


    }
}

@IBAction func recordButtonPressed(_ sender: Any) {
    if !isRecording {
        startRecording()
    } else {
            stopRecording()
        }
    }


func startRecording() {
    guard recorder.isAvailable else {
        print("Recording not available at this time")
        return
    }
    if micToggle.isOn {
        recorder.isMicrophoneEnabled = true
    } else {
        recorder.isMicrophoneEnabled = false
    }
    recorder.startRecording { (error) in
        guard  error == nil else {
            print("There was an error startng the recording.")
            return
        }
        //Call DispatchQueue to update UI in the main thread rather than background
        DispatchQueue.main.async {
            self.micToggle.isEnabled = false
            self.recordButton.setTitleColor(#colorLiteral(red: 0.521568656, green: 0.1098039225, blue: 0.05098039284, alpha: 1), for: .normal)
            self.recordButton.setTitle("Stop", for: .normal)
            self.statusLabel.textColor = #colorLiteral(red: 0.521568656, green: 0.1098039225, blue: 0.05098039284, alpha: 1)
            self.statusLabel.text = "Recording..."
            self.isRecording = true

            print("Started Recording")
        }
    }
}


func stopRecording() {

    recorder.stopRecording { (preview, error) in

        guard preview != nil else {
            print("Preview controller not available")
            return
        }

        let alert = UIAlertController(title: "Recording finished", message: "Would you like to share or delete your recording?", preferredStyle: .alert
        )

        let deleteAction = UIAlertAction(title: "Delete", style: .destructive, handler: { (action) in
            self.recorder.discardRecording {
                print("Recording discarded successfully.")
            }
        })

        //First try:
        let recordedVideo = "Video goes here!" //I don't know how to modify this to get the video content.
        let activityViewController : UIActivityViewController = UIActivityViewController(
            activityItems: [recordedVideo], applicationActivities: nil)
        self.present(activityViewController, animated: true, completion: nil)

        //Second try:
        //This allows me to edit and save the video, but not share it.
        let shareAction = UIAlertAction(title: "Share", style: .default, handler: { (action) in
            preview?.previewControllerDelegate = self
            self.present(preview!, animated: true, completion: nil)
        })

//            //Third try: not working!
//            var mode: RPPreviewViewControllerMode
//             let shareAction = UIAlertAction(title: "Share", style: .default, handler: { (action) in
//                preview?.mode = .share // The error is: 'mode' has been explicitly marked unavailable here (ReplayKit.RPPreviewViewController)
//                preview?.previewControllerDelegate = self
//                self.present(preview!, animated: true, completion: nil)
//            })


        alert.addAction(deleteAction)
        alert.addAction(shareAction)
        self.present(alert, animated: true, completion: nil)

        self.isRecording = false
        self.viewReset()
    }
}

func viewReset() {
    micToggle.isEnabled = true
    statusLabel.text = "Ready to Record"
    statusLabel.textColor = #colorLiteral(red: 0, green: 0, blue: 0, alpha: 1)
    recordButton.setTitle("Record", for: .normal)
    recordButton.setTitleColor(#colorLiteral(red: 0.2994912565, green: 0.7500386834, blue: 0.3387371898, alpha: 1), for: .normal)
}

func previewControllerDidFinish(_ previewController: RPPreviewViewController) {
    dismiss(animated: true, completion: nil)
}

}

Maybe it is because of .automatic modal presentation 'cause in iOS 13 it doesn't cover full screen when you popup your controller. So, try .fullScreen, it helps me:

func stopRecording() {
    recorder.stopRecording { (preview, error) in

        guard preview != nil else {
            print("Preview controller not available")
            return
        }

        let alert = UIAlertController(title: "Recording finished", message: "Would you like to share or delete your recording?", preferredStyle: .alert
        )

        let deleteAction = UIAlertAction(title: "Delete", style: .destructive, handler: { (action) in
            self.recorder.discardRecording {
                print("Recording discarded successfully.")
            }
        })

        let shareAction = UIAlertAction(title: "Share", style: .default, handler: { (action) in
            // Try .fullScreen
            preview?.modalPresentationStyle = .fullScreen
            preview?.previewControllerDelegate = self
            self.present(preview!, animated: true, completion: nil)
        })


        alert.addAction(deleteAction)
        alert.addAction(shareAction)
        self.present(alert, animated: true, completion: nil)

        self.isRecording = false
        self.viewReset()
    }
}