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Jump to a random postGit basics for iOS developers
Published on: January 3, 2024I’ll just say this right off the bat. There’s no such thing as git “for iOS Developers”. However, as iOS Developers we do make use of git. And that means that it makes a lot of sense to understand git, what it is, what it’s not, and most importantly how we can use it effectively and efficiently in our work. In this post, I’d like to outline some of the key concepts, commands, and principles that you’ll need to know as an iOS Developer that works with git. By the end of this post you will have a pretty good...
Read more...Making your SwiftData models Codable
Published on: August 15, 2023In a previous post, I explained how you can make your NSManagedObject subclasses codable. This was a somewhat tedious process that involves a bunch of manual work. Specifically because the most convenient way I've found wasn't all that convenient. It's easy to forget to set your managed object context on your decoder's user info dictionary which would result in failed saves in Core Data. With SwiftData it's so much easier to define model objects so it makes sense to take a look at making SwiftData models Codable to see if it's better than Core Data. Ultimately, SwiftData is a wrapper...
Read more...SwiftUI’s Bindable property wrapper explained
Published on: June 30, 2023WIth the introduction of Xcode 15 beta and its corresponding beta OSses (I would say iOS 17 beta, but of course we also get macOS, iPadOS, and other betas...) Apple has introduced new state mangement tools for SwiftUI. One of these new tools is the @Bindable property wrapper. In an earlier post I explained that @Binding and @Bindable do not solve the same problem, and that they will co-exist in your applications. In this post, I would like to clarify the purpose and the use cases for @Bindable a little bit better so that you can make better decisions when...
Read more...What’s the difference between @Binding and @Bindable
Published on: June 10, 2023With iOS 17, macOS Sonoma and the other OSses from this year's generation, Apple has made a couple of changes to how we work with data in SwiftUI. Mainly, Apple has introduced a Combine-free version of @ObservableObject and @StateObject which takes the shape of the @Observable macro which is part of a new package called Observation. One interesting addition is the @Bindable property wrapper. This property wrapper co-exists with @Binding in SwiftUI, and they cooperate to allow developers to create bindings to properties of observable classes. So what's the role of each of these property wrappers? What makes them different...
Read more...What’s the difference between Macros and property wrappers?
Published on: June 6, 2023With Swift 5.9 and Xcode 15, we have the ability to leverage Macros in Swift. Macros can either be written with at @ prefix or with a # prefix, depending on where they're being used. If you want to see some examples of Macros in Swift, you can take a look at this repository that sheds some light on both usage and structure of Macros. When we look at Macros in action, they can look a lot like property wrappers: @CustomCodable struct CustomCodableString: Codable { @CodableKey(name: "OtherName") var propertyWithOtherName: String var propertyWithSameName: Bool func randomFunction() { } } The example...
Read more...Tips and tricks for exploring a new codebase
Published on: April 28, 2023As a developer, joining a new project or company is often a daunting and scary task. You have to get aquatinted with not just a whole new team of people, but you also have to familiarize yourself with an entirely new codebase that might use new naming conventions, follows patterns that you’re not familiar with, or even uses tooling that you’ve never seen before. There are plenty of reasons to be overwhelmed when you’re a new member of any engineering team, and there’s no reason to feel bad about that. In the past two years, I’ve done a lot of...
Read more...Understanding unstructured and detached tasks in Swift
Published on: April 13, 2023When you just start out with learning Swift Concurrency you’ll find that there are several ways to create new tasks. One approach creates a parent / child relationship between tasks, another creates tasks that are unstructured but do inherit some context and there’s an approach that creates tasks that are completely detached from all context. In this post, I will focus on unstructured and detached tasks. If you’re interested in learning more about child tasks, I highly recommend that you read the following posts: Running tasks in parallel with Swift Concurrency’s task groups Running tasks concurrently with Swift Concurrency’s async...
Read more...The basics of structured concurrency in Swift explained
Published on: March 17, 2023Swift Concurrency heavily relies on a concept called Structured Concurrency to describe the relationship between parent and child tasks. It finds its basis in the fork join model which is a model that stems from the sixties. In this post, I will explain what structured concurrency means, and how it plays an important role in Swift Concurrency. Note that this post is not an introduction to using the async and await keywords in Swift. I have lots of posts on the topic of Swift Concurrency that you can find right here. These posts all help you learn specific bits and...
Read more...Setting up a simple local web socket server
Published on: January 24, 2023Every once in a while I find myself writing about or experimenting with web sockets. As an iOS developer, I’m not terribly familiar with setting up and programming servers that leverage web sockets beyond some toy projects in college. Regardless, I figured that since I have some posts that cover web sockets on my blog, I should show you how I set up the socket servers that I use in those posts. Before you read on, I’m going to need you to promise me you won’t take the code I’m about to show you to a production environment… You promise?...
Read more...Iterating over web socket messages with async / await in Swift
Published on: January 24, 2023In iOS 13, we gained the ability to easily send and receive data using web sockets through URLSession. With async/await, we gained the ability to fetch data from servers using the await keyword and we can iterate over asynchronous sequences using async for loops. We can even read data from a URL one line at a time by calling the lines property on URL: let url = URL(string: "https://donnywals.com")! for try await line in url.lines { // use line } While this is really cool and allows us to build apps that ingest data in real time if the server...
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