DAY 99


Today is the last consolidation day of this 100 Days challenge, and we’ll be looking over what you’ve learned before diving straight into your toughest challenge yet.

I know the thought of a tough challenge might not be welcome at this point, because you’re almost certainly tired. But as the Greek philosopher Epictetus once said, “the greater the difficulty the more glory in surmounting it” – this is a biggie, but you’ll feel great when you’re done because you’ll have had to exercise so many of the skills you’ve learned over these past few months.

Although biometric authentication is an interesting topic – and certainly an important one if you happen to be on a team building apps for a bank! – the real highlights of these last days have been more Core Graphics practice and dipping a toe in Instruments. Both of these are skills that will last you years. Sure, you might not remember the exact code required to make clipping masks in Core Graphics, or the precise button to press in Instruments to find the problem you’re hunting for, but you know where to look, and, more importantly, you know what you’re looking for.

As you might have learned yourself, when you’re facing a problem half the battle is figuring out what you’re looking for – what words to use, or even vaguely what kind of UIKit class might contain your answer. Since this course started you’ve gained so much experience across so many of Apple’s frameworks, but you will already have forgotten half of it.

And you know what? That’s OK. In fact, that’s normal. What you haven’t lost is all the code you wrote, which you can use as a reference for all your projects going forward. You also haven’t lost the concepts – you’re used to the idea of a table view delegate now, just like you’re used to storyboards, or view controllers, or Codable, and more. Those are the things that last, and, helpfully, those are the things that matter.

Today you have three topics to work through, one of which of is your challenge.

Note: Don’t worry if you don’t complete challenges in the day they were assigned. Today’s challenge is particularly tough, so it will probably be something you solve over a few days. Take your time, look back on previous projects to see how you can re-use ideas, don’t be afraid to experiment, and remember to ask for help if you need it.

Need help? Tweet me @twostraws!


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