@IBOutlet weak var myPDFView: PDFView!
 @IBOutlet weak var myThumbNailView: PDFThumbnailView!

 let pdfDoc = PDFDocument.init(url: pdfFilePath)
 self.myPDFView.document = pdfDoc
 self.myPDFView.autoScales = true

 myThumbNailView.pdfView = myPDFView
 myThumbNailView.thumbnailSize = CGSize.init(width:
 thumbNailDimension, height: 60)