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Comment by mfer | Hacker News Reader

Preview has issues with PDFs with form fields right now. It causes a bunch of people to need to install Acrobat for that use case. :(

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There is quite a bunch of "PDF" features around forms which basically only work with Adobe PDF and maybe one or two other ones. But good luck if non of them are available for you.

Worse many "office" people which create PDF's with form fields use Adobe tools, so they never see that what they hand out to thousends of students isn't working with >90% of PDF viewers....

It's because of this. Adobe hates us.

https://en.wikipedia.org/wiki/XFA

Further reading: https://eclecticlight.co/2019/06/18/pdf-without-adobe-23-the...

This sounds like a page in a playbook for a company that wants to maintain their monopoly.

- it is plausibly open

- there are enough edge cases that your tool is the only one that does it reliably.

This is similar to doc format - apple tools or openoffice can open it, but screw it up for everyone if they try to write it.

There is a wonderful rant about another adobe file format .PSD in this code here:

https://github.com/gco/xee/blob/master/XeePhotoshopLoader.m

That's beautiful. However, if I weren't an only child in two weeks I would take exception to that "old" bit describing the Uncle.

Installed Acrobat a few weeks ago for this use case specifically. I feel like Preview used to be a lot better at editing fields, recently it has been a real pain.

Are there not any alternatives to Adobe Acrobat Reader on macOS for editing fields and other use cases listed in the other comments?

Apple's Preview does a pretty good job with generic pdf forms. Unfortunately, Adobe has created multiple types of pdf forms using different technologies and very complex specs. Apple does not support all of these. (You can also find many cases of PDF forms using Adobe tools that do not round trip between platforms).

PDF Export does a good job of filing in the gaps.

https://pdfexpert.com

Not just complex specs. Some of them are proprietary.

There's some non-free options:

Editing/Form Fill/etc: Nitro[1]

Signing: Nitro[1], HelloSign[2], airSlate[3], Smallpdf[4] (limited functionality)

[1] https://www.gonitro.com

[2] https://www.hellosign.com

[3] https://www.airslate.com

[4] https://smallpdf.com

PDF has two types of forms: native and JS driven. I'd bet that the problems are with the JS. I'd also be willing to bet that Adobe makes Acrobat author forms in a way that intentionally breaks third party readers.

<airquotes>P</airquotes>DF

OTOH, Preview renders PDFs way better than Adobe Reader does. Tweaking the settings in AR didn't help either.

I only wish Preview would do two things:

- open files in "maximized" view.

- when opening a file, Left/Right arrow keys don't let you navigate the pages. Instead, they move the current page a few pixels left/right! (they work like horizontal scrollers)

Luckily other PDF editors do well with form fields and don't bundle a JS VM into their runtime.

That’s interesting. The iPad version works extremely well for editing.

Why would anyone in their right mind create a PDF form?

They are actually quite handy when the only allowed method of submission is via snail mail or fax. Much better than the alternative of printing an empty form and filling it all in by hand.

Man I don’t know what industry you’re in but I get 3-4 PDF’s a week.

What about Skim? It is the one I use.

It's good, but creates additional files for your annotations and comments - which btw, cannot be read in other software.

Yea, that is right.

For sure, however it seems like vast majority of use of PDF, (which is to view a printed document as it is) is addressed by Preview.

For stuff like sign a PDF and form are not things normal people need to use.

so the only people doing that are abby normal?

People keep saying this, but the form-filling tools are basically identical to Reader's. I don't get it.

What Preview doesn't support is JavaScript, as far as I can tell, so it can't work with "smart" PDF's, e.g. that will do calculations for you.

Is that what you're referring to? Or I'd love to know any specific issue you've run into with form fields.

The problem is that if the PDF forms where create with an Adobe program even things which should work with generic PDF might not do so because the Adobe program used JS or whatever below the cover.

EDIT: I looked into some of the PDFs again and it seems I had been wrong. Not sure what they use but it doesn't seem to be js.

EDIT EDIT: But I found other forms which where affected see my response below.

Is that a real thing?

I've encountered JavaScript-heavy PDF's before, but which were obviously so. (Automatically calculating values for one form field based on another, generating QR codes, etc.)

I've never come across a seemingly "normal" form PDF but which secretly used JavaScript for normal things like form filling, so that normal form-filling tools didn't work. I don't understand why the normal PDF type-in-a-text-box tool wouldn't work.

Have you actually come across this? Can you point to any examples?

I have run into this with regard to basic, but "slightly" more advanced features then text fields on forms in my university.

You can be sure that even Adobe won't add JS for forms with plain text fields. ;=)

EDIT: I looked into some of the PDFs again and it seems I had been wrong. Not sure what they use but it doesn't seem to be js.

Sorry about this.

Yes, as another commenter pointed out, Canadian govt citizenship forms, e.g. https://www.canada.ca/en/immigration-refugees-citizenship/se...

While (like it can be seen in the EDIT) the forms I found where not affected with JS. Other forms from my uni where.

For example I found following:

`/JS (if $this.getField\("inst1"$.value == "bitte auswählen"\){\r\nthis.getField$"Hinweis"$.display = 2\r\n} else\r\n{\r\nthis.getField$"Hinweis"$.display = 1\r\n}\r\n)$ /S /JavaScript`

This (in the given PDF) causes a "notice" overlapped on top of other form fields to disappear once the first multiple choice field was selected.

So if you try to fill it out without JS some form fields are not visible (but selectable by tab). Luckily it's not included in prints.

The Canadian govt forms like Visa application forms or Tax forms don't work on any Linux pdf tool that I tested with. The pdf would display empty with a JS error message. This was a few years ago though.

Had to install the linux version of Adobe, which is many years out of date now.

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