Mystery Beta

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Something old, something new »

I've just released the beta of my new book The Mystery of the Mutating Mannequin.

This book explores dataflow in SwiftUI apps and the beta includes the first three chapters.

Chapter 1 looks at simple views with no state. We focus on how the view is assembled and, in particular, what modifiers add to the view hierarchy.

Chapter 2 introduces state and we look at simple properties and @State and look at when views redraw and why. It's material that we know about SwiftUI but here we have the ability to poke and prod a bit and get to understand the mechanism a little better.

Chapter 3 is an exploration of shared state. We begin with two views that use @Binding to share state and then move to a more robust model that uses @ObservableObject and @Published. We replace this solution that uses Combine with AsyncStreams and then look at @Observable objects (which are not the same as @ObservableObjects) and @Bindable.

Up next Chapter 4 manages an object graph manually and with Core Data with a tiny preview of SwiftData. Chapter 5 is an introduction to SwiftData.

Do you know all this stuff? Probably. But I have to say I'm a little embarrassed to admit that I didn't know some of the stuff I was sure I knew.