BLACK FRIDAY: Save 50% on all books and bundles! >>

Bucket List: Wrap up

Paul Hudson    @twostraws   

This was our biggest project yet, but we’ve covered a huge amount of ground: adding Comparable to custom types, finding the documents directory, integrating MapKit, using biometric authentication, secure Data writing, and much more. And of course you have another real app, and hopefully you’re able to complete the challenges below to take it further.

Between this and Instafilter you’ve now seen how to embed any part of UIKit into your app – any UIView or UIViewController can now be placed inside SwiftUI. This massively widens the types of apps you can build, as long as you’re able to spend the time learning some UIKit. Over time SwiftUI will grow and expand what it’s capable of, but right now it’s important to know its limits and play to its strengths!

Review what you learned

Anyone can sit through a tutorial, but it takes actual work to remember what was taught. It’s my job to make sure you take as much from these tutorials as possible, so I’ve prepared a short review to help you check your learning.

Click here to review what you learned in this project.


One of the best ways to learn is to write your own code as often as possible, so here are three ways you should try extending this app to make sure you fully understand what’s going on.

  1. Our + button is rather hard to tap. Try moving all its modifiers to the image inside the button – what difference does it make, and can you think why?
  2. Having a complex if condition in the middle of ContentView isn’t easy to read – can you rewrite it so that the MapView, Circle, and Button are part of their own view? This might take more work than you think!
  3. Our app silently fails when errors occur during biometric authentication. Add code to show those errors in an alert, but be careful: you can only add one alert() modifier to each view.

Save 50% in my Black Friday sale.

Sponsor Hacking with Swift and reach the world's largest Swift community!

Buy Pro Swift Buy Swift Design Patterns Buy Testing Swift Buy Hacking with iOS Buy Swift Coding Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift (Vapor Edition) Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Advanced iOS Volume Three Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with macOS Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Server-Side Swift (Kitura Edition) Buy Beyond Code

Was this page useful? Let us know!

Average rating: 4.9/5

Link copied to your pasteboard.