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iosswiftxcodepdfpdfkit

Xcode PDFKit form automatic calculation

This may not be possible, but after searching for quite a while I thought I would ask the question to either point me in the right direction or confirm it's not possible!

  • I have iOS app (Xcode swift) that displays pdf documents using PDFKit
  • I have several PDF forms created in acrobat that have simply calculations which update automatically as numbers are entered or checkboxes ticked i.e. adding numbers together, totalling the number of checkboxes ticked.
  • Whilst each form has only simply calculations, each has a different number of input fields.

Is it possible in PDFKit (or another method) to display these PDF forms in an iOS app and have them perform the calculations without having to re-write in Xcode the calculation per form, i.e. basically make use of the embedded javascript that is part of the PDF form?

At present, when I display the form, while I can edit the the editable textfields, the calculation doesn't occur.

Appreciate any help

Solution

  • I've discussed this at WWDC 2017 when Apple introduced PDFKit for iOS.

    Their answer is that JavaScript is not a feature that they are planning to support. This is consistent with the level of support in Apple Preview on macOS and also Safari on iOS/macOS - none.

    3rd-party PDF SDKs often also include JavaScript implementations. The spec is quite complex, so it's unlikely that you find a product implementing all of the 894 pages (including things like the Japanese Emperor calendar).

    PSPDFKit supports the common JavaScript API necessary for most forms to validate correctly. An easy way to check if your forms are supported is trying it in PDF Viewer (free, ad-free app for iOS and Android)