Ours is an open-source Mac application localized by volunteers. These volunteers will do their work on special localization builds of the software (with unstripped nibs), then send us the changes to integrate into the original xib and strings files.
The problem is that, while there is a way to integrate string changes without blowing away previous size changes, I can't see a way to integrate new string and size changes (as when we add or replace views).
The only way to do both that I can see is for localizers to work directly with the original xibs and send us diffs. That means they have to download the entire source code, not just a localizable version of the release, work in Xcode as well as IB, and either run the diff command themselves (per xib) or install and use Mercurial.
Is there any better way for a xib-based application?
Best Answer
UPDATE January 2014: Apple’s ‘autolayout’ code combined with their ‘Base’ localization stuff took most my ideas and improved on them. I recommend against using my old tools that I talk about in this answer. But, also, man was I right!
I strongly strongly STRONGLY recommend against frame changes in localizations. I know this runs counter to Apple's advice, but there are SO MANY problems with allowing frame changes - you end up with a billion edge cases.
Imagine you have 10 XIBs in your app, and you support 12 languages. You've got 120 different layouts to support, now. You just can't do this.
Change the strings, leave the views where they are. Make 'em bigger in ALL languages, if you need to. It sounds like this shouldn't work but it does. (I won three Apple Design Awards with an app that's localized in 10 or so languages this way.)
Specifics:
For radio and checkboxes, just let them extend far to the right, beyond the last English character. That also provides a nice big landing area for imprecise mousers.
For buttons, they should be wide anyhow, because it never looks good to have text cramped in the middle of the buttons.
For titles on tableview columns, you should autosize when you load 'em up, if needed.
For explanatory text, you should have some extra space to the right, and maybe an extra line. It just makes the English version of the XIB seem less cluttered. Sure, the Germans are going to see a slightly tighter XIB, but, hey, they're Germans -- they're probably used to that. There's probably even a German word for it. "Deutscheninterfakkenclutterlongen."
If a text field is centered, just add equal space on both sides. There's no reason not to.
I've combined this with scripts that suck all the strings out of my XIBs and put them in .strings files, and then dynamically put the strings back at run-time, so anyone can localize my app without any special tools. Just drop in a bunch of .strings files and run it!
Blog post including full source: [Lost in Translations]¹.