This blog post was written with the assistance of ChatGPT. When integrating UIKit components into SwiftUI using UIViewRepresentable, you might come across the context.environment property. While it looks simple on the surface, it hides a powerful mechanism: environment-driven updates. In this post, we’ll explore what context.environment does, how SwiftUI tracks it, and how it can cause Read more…
When I attempt to remove a disk from the AppleRAID JBOD APFS I get the error: Also there is a similar error when trying to add a disk: No size options were set for the volume in the container. And I experimented with setting the reserve and quota but it Read more…
To upgrade old Combine code in an ObservableObject that had its lifetime tied to a SwiftUI View using @StateObject we can replace it with .task and since async/await gives us a lifetime like a reference type we can do away with the object altogether. In the Combine version of the Read more…
When you mark a class as @Observable you can no longer use didSet because the macro converts it to a computed property, e.g. a simple: When expanded becomes: As you can see test has become a computed property that is a wrapper around a private _test property, a bit like Read more…
The built-in @Query does not currently support dynamic changes, instead we can use @DynamicQuery from the SwiftDataX open-source package to achieve it. The query declaration looks like this: By default that will load all Prospect model objects, sorting them by name. If the fetchDescriptor property is later changed and this View is Read more…
SwiftUI’s design takes advantage of equality to decide if things should be updated. Measurement (backed by NSMeasurement) has something interesting in its Equatable implementation: This means that 0kg is equal to 0g despite their unit being different. This makes sense for comparing weights but not for using it to decide Read more…
Reposted from: https://forums.swift.org/t/how-to-use-observation-to-actually-observe-changes-to-a-property/67591/18 I thought I’d share an example of how I am currently using it. I wanted to make an object that maintains a sorted order of the main model’s objects. I used withObservationTracking to update if either the sort order local to this object is changed or if the particular Read more…
I came across this StackOverflow question How do I access the SwiftData container from outside of SwiftUI? but it turns out they needed to use the container inside an AppIntent. I knew the way to inject objects into AppIntents is via the AppDependencyManager but I’d never actually tried it with Read more…
Health warning: In general I would not recommend this approach. View data should be @State simple values or custom structs with mutating func for testable logic, passed down as let for read only, computed vars for transforming, or @Binding var for read/write. @Observable is designed for data models, e.g. loading Read more…
If you attempt to init another instance of CLMonitor with the same name it crashes with: Since I wanted to use the same monitor from different tasks I needed to turn it into a singleton and came up with this: This allows this kind of thing to work without crashing: Read more…