A common use of a Core Data store is to cache data from a remote resource locally to support offline functionality of an app. There are multiple ways to implement a caching mechanism and many of them don’t involve Core Data. For example, you could simply fetch a JSON file Read more…
Every once in a while I look at a feature in Swift and I fall down a rabbit hole to explore it so I can eventually write about it. The OptionSet protocol is one of these Swift features. If you’ve ever written an animation and passed it a list of Read more…
When you’ve added Core Data to your SwiftUI project and you have some data stored in your database, the next hurdle is to somehow fetch that data from your Core Data store and present it to the user. In this week’s post, I will present two different ways that you Read more…
If you’ve ever wanted to decode a bunch of JSON data into NSManagedObject instances you’ve probably noticed that this isn’t a straightforward exercise. With plain structs, you can conform your struct to Codable and you convert the struct from and to JSON data automatically. For an NSManagedObject subclass it’s not Read more…
Unit testing is an important skill in the toolbox of any engineer. Knowing how to write a reliable, robust test suite helps you write reliable and robust code. If you’ve followed my introduction to unit testing part one and part two, or if you’re experienced with unit testing you know Read more…
In Xcode 12 you can create projects that no longer use an AppDelegate and SceneDelegate to manage the application lifecycle. Instead, we can use Swift’s new @main annotation to turn a struct that conforms to the App protocol into the main entry point for our applications. When you create a Read more…
As developers, we constantly deal with layers of abstractions that make our lives easier. We have abstractions over low level networking operations that allow us to make network calls with URLSession. Core Data provides an abstraction over data persistence that can be used to store information in an sqlite database. Read more…
Starting with iOS 14, we can write apps that are fully built using SwiftUI, dropping the need to have AppDelegate and SceneDelegate files entirely. For as long as I remember, I’ve handled deeplinks in my AppDelegate and for the past year in the SceneDelegate. So when Apple introduced developers to Read more…
Tons of apps that we build feature lists. Sometimes we build lists of settings, lists of todo items, lists of our favorite pictures, lists of tweets, and many other things. Some of these lists could scroll almost endlessly. Think of a Twitter timeline, a Facebook feed or a list of Read more…
Apple introduced SF Symbols in iOS 13. SF Symbols allow developers to easily integrate icons in their apps. The SF Symbols icons integrate really well with the default system font, and provide a consistent look throughout the system. In iOS 14, Apple added over 750 new icons to the SF Read more…