This app is the most complex one we’ve built so far. Yes, there are multiple views, but we also strayed away from lists and forms and into our own scrolling layouts, using GeometryReader
to get precise sizes to make the most of our space.
But this was also the most complex Swift code we’ve written so far – generics are an incredibly powerful feature, and once you add in constraints you open up a huge range of functionality that lets you save time while also gaining flexibility.
You’re also now starting to see how useful Codable
is: its ability to decode a hierarchy of data in one pass is invaluable, which is why it’s central to so many Swift apps.
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.
MissionView
, below the mission badge. You might choose to format this differently given that more space is available, but it’s down to you.MissionView
is a great candidate, but if you followed my styling then you could also move the Rectangle
dividers out too.ContentView
that toggles between showing missions as a grid and as a list.Hacking with Swift+ subscribers can get a complete video solution for this checkpoint here: Solution to Moonshot. If you don’t already subscribe, you can start a free trial today.
Tip: For that last one, your best bet is to make all your grid code and all your list code two separate views, and switch between them using an if
condition in ContentView
. You can’t attach SwiftUI modifiers to an if
condition, but you can wrap that condition in a Group
then attach modifiers to there, like this:
Group {
if showingGrid {
GridLayout(astronauts: astronauts, missions: missions)
} else {
ListLayout(astronauts: astronauts, missions: missions)
}
}
.navigationTitle("My Group")
You might hit some speed bumps trying to style your list, because they have a particular look and feel on iOS by default. Try attaching .listStyle(.plain)
to your list, then something like .listRowBackground(Color.darkBackground)
to the contents of your list row – that should get you a long way towards your goal.
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