It was the mid 1990s and I was about thirteen. These were the days of Netscape Navigator and internet connections that made sound (if you know, you know) and delivered web pages slower than molasses flowin’ up hill on a cold winter’s day. So… the pages were simple. And I had a Star Wars fan page I l...

When you log into the Apple Developer portal, you can easily download a restore image (ipsw file) for beta versions of macOS, but it’s not helpful if you want to install macOS on a separate volume on your existing Mac. The actual macOS installer is much more useful. The only issue is that it’s not e...

Developing for iOS is a valuable and in-demand skill, but if you haven’t developed in the Apple world before, it can be surprisingly different. In this course, SwiftUI Fundamentals, you’ll quickly get up and running using Xcode 15, Swift, and SwiftUI to establish the foundational skills you need to ...

Developing for iOS is a valuable and in-demand skill, but it can be surprisingly different if you haven’t developed for Apple platforms before. In this course, iOS 17 Fundamentals, you’ll quickly get up and running using Xcode 15, Swift 5, and SwiftUI to build great iOS apps and tap into the latest ...

Building Blocks These three building blocks will get you there: A ModelContainer instance One or more instances of your @Model class(es) Inserting those model instances into your ModelContainer’s mainContext Let’s take those building blocks one at a time. Initialize a ModelContainer Suppose that you...

System Configuration First things first: you need the following before you can get started with SwiftData… You need to install Xcode 15 on your Mac. You need to set your app’s minimum deployment target to macOS 14, iOS 17, tvOS 17, or watchOS 10. Your app needs to use SwiftUI – SwiftData does not wo...

Designing efficient and dynamic apps is essential for taking your iOS developer skills to the next level. In this course, Building iOS User Interfaces with SwiftUI, you’ll build upon the basic knowledge of iOS development you’ve already gained in order to build compelling iOS apps that engage your u...

Persistence prevails: Dave shares his iOS developer journey After watching Dave Jacobsen’s story on YouTube, I found myself asking, “When would I have given up if I were in Dave’s shoes?” He shares about the sobering reality of how much effort and dedication it really takes to transition careers. Bu...

Whyyy would I need an old version of Xcode? Valid question – it’s not often you’ll need one. Two reasons off the top of my head though: 1) To compare with your previous experience Perhaps you’re just wanting to see what things “used to be like”. Maybe you’re struggling with the infamous “this code w...

Developing for iOS is a valuable and in-demand skill, but if you haven’t developed in the Apple world before, it can be surprisingly different. In this course, iOS 14: Getting Started, you’ll quickly get up and running using Xcode 12, Swift 5, and SwiftUI to build great iOS apps and tap into the lat...

This is merely a breadcrumb for finding the Apple Developer documentation page where all of the possible SwiftUI Environment keys are listed. Resources Apple Documentation ➡️ SwiftUI ➡️ State and Data Flow ➡️ EnvironmentValues

June is an invigorating time for iOS developers worldwide. Invigorating… And exhausting. Me personally? The flurry of new-ness often has me feeling overwhelmed. WWDC - The Worldwide Developer Chase When it comes time for WWDC, are you like me? Do you conjure up a mental image of a race? It’s as if a...

Manually Testing StoreKit Code Development Workflow Changes The previous workflow for setting up in-app purchases was a bit disjointed. You’d have to create your app in Xcode… then jump out to App Store Connect to define your app there… set up your digital products there (in App Store Connect)… and ...

Monetizing apps is challenging. In this course, Implementing In-App Purchases on iOS, you’ll learn to offer digital products and services directly within your app as in-app purchases. Resources Implementing In-App Purchases on iOS Course Outline First, you’ll explore how to translate business requir...

Setting the stage with a use case for checking the original_application_version The task appears to be simple. Suppose that… You have an existing app on the app store that’s currently at version 1.2 You want to shift to the “freemium” model by implementing in-app purchases starting with version 1.3 ...

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CPU cannot execute an instruction Sometimes we developers don’t play fair with the CPU. Suppose that I wrote some code that ended up telling the CPU to divide by zero. That’s… impossible… for you and the CPU. iOS is ensuring its own stability iOS may be enforcing a fundamental requirement or policy ...

Never change code without reproducing the problem first Reproducing the problem is a critical first step in debugging. Before you start scouring your code… Before you start setting breakpoints… Before you start using tools or changing things… See if you can cause the bug to happen again. The goal of...

Does it ever help you to narrow the scope of overwhelming topics like “debugging”? It helps me. When you’re new to something like iOS development, you may find yourself stepping into a world of problems. Everyone around you is always fixing something it seems! All kinds of problems can happen when y...

Bugs are bound to happen. Getting rid of them is an essential skill if you want to keep your sanity when building apps. In this course, you will learn a set of thinking skills to couple with the fundamental tools that Xcode provides you for finding and fixing flaws in your apps. 🐞1.5 hours 🦟To the p...

Once you’ve passed an NSManagedObjectContext instance to your SwiftUI View, you’ll need to pull data out of your Core Data persistent store with a fetch request. First Things First The remainder of this how-to assumes that you’ve already got a way to initialize the Core Data stack. Ticking the ‘Use ...

Step one to using Core Data with SwiftUI is to initialize the Core Data stack and pass an instance of your NSManagedObjectContext to your view. First Things First The remainder of this how-to assumes that you’ve already got a way to initialize the Core Data stack. Ticking the ‘Use Core Data’ checkbo...

How does Apple intend for us to use Core Data with SwiftUI? They gave us a path forward with the most recent beta release of iOS 13 (Beta 5 at the time of this writing)! Resources Blog Idea List SwiftUI Example Xcode Project Data Flow Through SwiftUI - WWDC 2019 Session 226 First Things First To wor...

NSPersistentCloudKitContainer is brand new with Xcode 11 and iOS 13. It works… kind of… sometimes… I’m keeping this list of buggy behavior to help keep my head straight. I’ve also filed bug reports on each. Hopefully others in the iOS community who are experimenting with NSPersistentCloudKitContaine...

Resources SwiftUI Essentials Tutorials as Playgrounds Apple's SwiftUI tutorials Why Playgrounds? I’ve been making my way through Apple’s SwiftUI tutorials. If you’re anything like me, you learn by tinkering with things. Change the modifiers, reposition Text, use a different Image, and see what happe...

Imagine writing some Swift code. You want to share it across multiple apps, so you build a framework. You compile it with the Swift 4.0 compiler. Now imagine Apple announces Swift 4.1. Sweet! You decide to build a new app and compile it with the Swift 4.1 compiler. Ah, but your apps needs some of th...

If you constantly run the same set of commands at the command line, why not automate that? I found myself typing the same things over and over to deploy this website. Here’s how I encapsulated it into a script that saves me keystrokes at the command line. 1) Create a new text file with a .sh extensi...

“ABI” stands for “Application Binary Interface”. The word “interface” means the same as it does in other places where you hear the word. If a human wants to interact with a computer, s/he needs a way to engage with it. A user interface is the point where humans and computers communicate with one ano...

Apps aren’t “dumb”. Apps do things. Smart things. The question is: Where do the “smart parts” go? So how you smart or how dumb should NSManagedObject subclasses be? What code should you write in one of these? What should you not? TLDR; Keep NSManagedObjects about Core Data-y things. Ask, “Does this ...

Setting the Stage Suppose one of the NSManagedObject subclasses from your Core Data data model looked like this: 1 2 3 4 5 6 public class BlogIdea: NSManagedObject { @NSManaged public var ideaTitle: String? @NSManaged public var ideaDescription: String? } Suppose that you also have a class that will...