PDFView - How to autoscale and still load first page?

Question

If autoScales is disabled pdfView shows the 1st page (image 1) but if it is enabled PDFview scrolls to second page (image 2) on iPhoneX.

Github - https://github.com/2raptor/DownloadPDF

import UIKit
import PDFKit

class PDFViewController: UIViewController {
    var pdfView = PDFView()
    var pdfURL: URL?

    override func viewDidLoad() {
        super.viewDidLoad()

        pdfView.translatesAutoresizingMaskIntoConstraints = false
        if let pdfURL = pdfURL,
            let document = PDFDocument(url: pdfURL) {
            pdfView.document = document
            pdfView.autoScales = true
        }

        view.addSubview(pdfView)

        // Add contstraints
        pdfView.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor).isActive = true
        pdfView.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor).isActive = true
        pdfView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor).isActive = true
        pdfView.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor).isActive = true
    }
}

Tried few solutions but didn't work.

// after `pdfView.document = document` above
            if let firstPage = document.page(at: 0) {
                let firstPageBounds = firstPage.bounds(for: pdfView.displayBox)
                pdfView.go(to: CGRect(x: 0, y: firstPageBounds.height, width: 1.0, height: 1.0), on: firstPage)
            }

Curious if you ever found a solution? I have the same issue. — Mark Krenek, Apr 08 '20 at 15:20

Prabhakar Kasi · Accepted Answer · 2020-04-10T05:41:50.850

Setting usePageViewController before setting autoScales solved the issue

pdfView.usePageViewController(true)

Complete solution that works

import UIKit
import PDFKit

class PDFViewController: UIViewController {
    var pdfView = PDFView()
    var pdfURL: URL?

    override func viewDidLoad() {
        super.viewDidLoad()

        pdfView.translatesAutoresizingMaskIntoConstraints = false
        if let pdfURL = pdfURL,
            let document = PDFDocument(url: pdfURL) {
            pdfView.document = document
            pdfView.usePageViewController(true)
            pdfView.autoScales = true
        }

        view.addSubview(pdfView)

        // Add contstraints
        pdfView.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor).isActive = true
        pdfView.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor).isActive = true
        pdfView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor).isActive = true
        pdfView.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor).isActive = true
    }
}

Unfortunately, this will not result in a single continuous page as in your original post. — David, Jan 20 '21 at 15:24
That's correct. But I didn't have the requirement of showing single page at a time, so I was okay with this solution. I followed this article https://medium.com/@ji3g4kami/make-a-ebook-reader-with-pdfkit-in-swift-6010f82bd51 Please see if this helps. — Prabhakar Kasi, Jan 27 '21 at 23:28

score 1 · Answer 2 · answered Jan 20 '21 at 15:23

1

In my case there was a bug in iOS 12.4 with pdfView.autoScales = true and there was not much that I could do. Try upgrading to iOS 14.3 to see if it fixes this.

answered Jan 20 '21 at 15:23

David

81
1
6

score 1 · Answer 3 · answered Mar 10 '21 at 13:30

1

Solution: https://stackoverflow.com/a/66565702/6404249

I can't copy-paste answer for you, but i hope it will helps you!

answered Mar 10 '21 at 13:30

Daniel Smith

720
7
13

PDFView - How to autoscale and still load first page?

3 Answers3