iOS Monospace Font Bug – A JavaScript Fix

December 20, 2010

After struggling through trying to find solutions for the iOS monospace font problem, I was able to cobble together a JavaScript fix.

To summarize the problem: in fixed-width fonts on iOS, spaces, question marks, and hyphens/dashes all display wider than letters, numbers, and other symbols. Replacing the dashes with –es fixed them, but there was no HTML entity fix for question marks or spaces (all the special spaces display either wider or narrower than regular characters).

I was experimenting with different ways to try to get the characters the same width, and I was going to try wrapping the “bad” characters in a span so I could style them differently. What I found was that characters wrapped in a span display at a different width than either the “normal” or “bad” characters not in a span, so it didn’t serve my purpose. But, I also noticed that (almost) all characters (both “normal” and “bad”) displayed at the same width when they were placed into spans!

Incidentally, spaces still didn’t display at the right width, nor did any of the special space HTML entities. (It seemed inconsistent–spaces seemed OK on iPad, but not on iPhone.) The best solution I’ve found so far (and it’s not a good one for the sake of copy-pasting text) is to replace the spaces with an underscore, and style the spaces to be non-visible.

So a solution would go through my code to output, take all the text (non-HTML) characters, and wrap each of them in a span. This was easier on the client-side than the server-side, because the browser has already parsed my document into DOM objects, so it’s easy to tell what’s plain text characters.

The JavaScript function I wrote takes a node, and iterates through its child hierarchy. Whenever it finds a text node, it splits it into characters, wraps each in a span, performs the extra steps I described above for spaces, and then inserts these spans into the DOM in place of the original text node.

Another limitation of this setup is that it can’t be used for editing text in textareas–it can only be used for displaying text.

Note: this has been tested very little! No warranty it won’t erase all your data. If you find cases where it doesn’t work, and you can make it better, let me know and I’ll post the updated version here.

Download the source, or check out an example of it in action, which allows you to see the text before and after the fix is applied.

Monospace Fonts on iOS

December 20, 2010

Today I just had what might be my biggest disappointment of the year: monospace fonts are not monospaced on iOS. Specifically, the hyphen and question mark are wider than other characters in Courier New on iOS. Of course, this completely messes up any kind of monospace-based layout you might want to do.

Here are the alternatives I’ve investigated that didn’t work:

  1. Leaving the programming industry. Unfortunately, I’m not smart enough to do anything else. On to more reasonable alternatives.
  2. Tried other installed fonts. Courier is supported, but has the same problem. Monaco isn’t supported. And that’s all the built-in font options.
  3. Web fonts. I searched through the Google Font Directory and found “Droid Sans Mono.” If that had worked, man, what a slap in the face, huh? Unfortunately, it exhibited the same problem.

Here are options that could or did work:

  1. In app store apps, custom views to lay out text. If you draw one character at a time, you can make sure they’re placed properly. Unfortunately, if you need to use this for an editor (as I do), that would mean re-implementing a ton of functionality.
  2. On the web, replace dashes with HTML entities. This works for webapps and UIWebViews. If you replace all dashes/hyphens with –, you will see an identical (in Courier New) looking dash, that is spaced properly. This works for displaying text, but wouldn’t work for editors, which are just displaying bare characters and not interpreting HTML entities. Also, this doesn’t solve the question mark problem.

Does anyone else have any suggestions?