How to add pdf to UIView, not pushViewController?

[aloveric]

No description provided.

[Y2JChamp]

this is my snippet:
`let remotePDFDocumentURLPath = item.url
let remotePDFDocumentURL = URL(string: remotePDFDocumentURLPath!)!
let document = PDFDocument(url: remotePDFDocumentURL)!

    let readerController = PDFViewController.createNew(with: document)
    
    let modalReaderController: PDFReaderViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "pdfreadercontroller") as! PDFReaderViewController
    present(modalReaderController, animated: true, completion: nil)
    modalReaderController.containerView.addSubview(readerController.view)
    modalReaderController.addChildViewController(readerController)
    
    readerController.view.translatesAutoresizingMaskIntoConstraints = false
    
    let top = NSLayoutConstraint(item: readerController.view, attribute: .top, relatedBy: .equal, toItem: modalReaderController.containerView, attribute: .top, multiplier: 1, constant: 0)
    let bottom = NSLayoutConstraint(item: readerController.view, attribute: .bottom, relatedBy: .equal, toItem: modalReaderController.containerView, attribute: .bottom, multiplier: 1, constant: 0)
    let leading = NSLayoutConstraint(item: readerController.view, attribute: .leading, relatedBy: .equal, toItem: modalReaderController.containerView, attribute: .leading, multiplier: 1, constant: 0)
    let trailing = NSLayoutConstraint(item: readerController.view, attribute: .trailing, relatedBy: .equal, toItem: modalReaderController.containerView, attribute: .trailing, multiplier: 1, constant: 0)
    modalReaderController.containerView.addConstraints([top, bottom, leading, trailing])`

[aloveric]

@Y2JChamp Thanks~~