QuickLook-iOS13.swift

extension ViewController: QLPreviewControllerDelegate {

        func previewController(_ controller: QLPreviewController, editingModeFor previewItem: QLPreviewItem) -> QLPreviewItemEditingMode {        
                return .createCopy
        }

        func previewController(_ controller: QLPreviewController, didSaveEditedCopyOf previewItem: QLPreviewItem, at modifiedContentsURL: URL) {
        
        let documentsDirectoryURL =  FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
        let currentTimeStamp = String(Int(NSDate().timeIntervalSince1970))
        let destinationUrl = documentsDirectoryURL.appendingPathComponent("newFile\(currentTimeStamp).\(modifiedContentsURL.pathExtension)")
        
        if FileManager.default.fileExists(atPath: destinationUrl.path) {
            debugPrint("The file already exists at path")
        }
        else{
            do {
                try FileManager.default.moveItem(at: modifiedContentsURL, to: destinationUrl)
                print("File moved to documents folder")
            } catch let error as NSError {
                print(error.localizedDescription)
                
            }
        }
    }
}