DAY 31


One of the three laws laid down by British science fiction writer Arthur C. Clarke is particularly well known: “any sufficiently advanced technology is indistinguishable from magic.”

It’s possible that you’re thinking Auto Layout is a bit of a black box, where magic happens to make sure all your rules are followed. But it isn’t: Auto Layout is actually straightforward most of the time, and as long as you make sure your constraints are a) complete, and b) non-contradictory, you shouldn’t have too many problems.

Today you have three topics to work through, and you’ll learn about advanced Visual Formatting Language and Auto Layout anchors. Once you’re done, please complete the project review then work through all three of its challenges.

If you’re keen to learn more about Auto Layout, I have an Auto Layout cheat sheet that gives you lots of example code to solve common problems.

If you’re feeling mathematically brave, there’s also a great talk by Agnes Vasarhelyi that goes into exactly how the Auto Layout algorithm works behind the scenes – it should prove there’s no magic once and for all!

Need help? Tweet me @twostraws!


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