/swiftui-patterns

@Observable — NOT ObservableObject

iOS 17+ Pattern

✅ Modern Pattern

import Observation

@Observable
class UserProfileModel {
    var name: String = ""
    var email: String = ""
    var isLoading: Bool = false

    func save() async {
        isLoading = true
        // Save logic
        isLoading = false
    }
}

// In SwiftUI view
struct ProfileView: View {
    let model: UserProfileModel

    var body: some View {
        TextField("Name", text: $model.name)
    }
}

❌ Deprecated Pattern

// NEVER use ObservableObject for new code
class UserProfileModel: ObservableObject {
    @Published var name: String = ""
    @Published var email: String = ""
}

Why @Observable?

Benefits:

• Less boilerplate — no @Published needed
• Better performance — fine-grained observation (only tracks accessed properties)
• Type-safe environment — @Environment(Type.self) instead of @EnvironmentObject
• Simpler bindings — @Bindable instead of @ObservedObject

Requirement: iOS 17.0+ / macOS 14.0+