Save a PDF from a WKWebView

Question

This questions pertains to macOS, not iOS.

Note that this question is being reported as a duplicate of this question. The answers on that page pertain either to iOS (irrelevant) or uses the deprecated WebView as a solution, which is exactly what my question is about in the first place.

So Apple has deprecated WebView in favor of WKWebView, but I'm not seeing a working solution for being able to export (or print) a PDF from the new view type. I've tried the following (and more) from within the delegate method webView(_ webView: WKWebView, didFinish navigation: WKNavigation!)

1.

    let pdfData = webView.dataWithPDF(inside: webView.frame)
    try? pdfData.write(to: URL(fileURLWithPath: "/filepath/to/test.pdf"))

This resulted in a literal blank pdf file.

2.

webView.takeSnapshot(with: nil) { (image, error) in
    if let error = error {
        print("Error: \(error)")
        return
    }
    guard let image = image else {
        print("No image")
        return
    }
    try? image.tiffRepresentation?.write(to: URL(fileURLWithPath: "/path/to/test.tif"))
}

And while this got actual content in the image, it was a (giant) rendered bitmap image having lost all of its textual/string data, which also only showed what was visible on screen, nothing beyond the edges of the window.

Meanwhile, following the numerous examples available on the web, using WebView works well and as expected. Am I to believe that Apple released a half baked replacement for a deprecated framework, or am I doing something wrong?

Does this answer your question? [Saving WebView to PDF returns blank image?](https://stackoverflow.com/questions/38191642/saving-webview-to-pdf-returns-blank-image) — Willeke, Jun 17 '20 at 08:10
No, the macOS answer on that page utilizes WebView (which is deprecated) and the other one is for iOS, which doesn't mirror the Mac side of things. — mredig, Jun 17 '20 at 10:00
Marked 2 might be using the old method. It might be interesting to reach out to see what Brett Terpstra is doing: https://marked2app.com — Paul Solt, Jun 18 '20 at 15:52
I had the same thought and already reached out to him! Unfortunately, he doesn't have an answer at this time either. :( — mredig, Jun 19 '20 at 22:31

score 3 · Accepted Answer · answered May 04 '22 at 22:18

This is now possible with WKWebView's createPDF method: https://developer.apple.com/documentation/webkit/wkwebview/3650490-createpdf

Here's an example:

func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
  let config = WKPDFConfiguration()
      
  //Set the page size (this can match the html{} size in your CSS
  config.rect = CGRect(x: 0, y: 0, width: 792, height: 612)
      
  //Render the PDF
  webView.createPDF(configuration: config){ result in
    switch result{
      case .success(let data):
        try! data.write(to: URL(fileURLWithPath: "/path/file.pdf"))
      case .failure(let error):
        print(error)
    }
  }
}

I have it working on both macOS and iOS. Hopefully this helps.

Thanks for the answer! Unfortunately, it's taken Apple so long to fix this I forgot why I even asked the question in the first place. — mredig, May 18 '22 at 04:40

Save a PDF from a WKWebView

1 Answers1