library-picturebook-activity/.claude/skills/ui-ux-pro-max/data/stacks/swiftui.csv

No,Category,Guideline,Description,Do,Don't,Code Good,Code Bad,Severity,Docs URL
1,Views,Use struct for views,SwiftUI views are value types,struct MyView: View,class MyView: View,struct ContentView: View { var body: some View },class ContentView: View,High,https://developer.apple.com/documentation/swiftui/view
2,Views,Keep views small and focused,Single responsibility for each view,Extract subviews for complex layouts,Large monolithic views,Extract HeaderView FooterView,500+ line View struct,Medium,
3,Views,Use body computed property,body returns the view hierarchy,var body: some View { },func body() -> some View,"var body: some View { Text(""Hello"") }",func body() -> Text,High,
4,Views,Prefer composition over inheritance,Compose views using ViewBuilder,Combine smaller views,Inheritance hierarchies,VStack { Header() Content() },class SpecialView extends BaseView,Medium,
5,State,Use @State for local state,Simple value types owned by view,@State for view-local primitives,@State for shared data,@State private var count = 0,@State var sharedData: Model,High,https://developer.apple.com/documentation/swiftui/state
6,State,Use @Binding for two-way data,Pass mutable state to child views,@Binding for child input,@State in child for parent data,@Binding var isOn: Bool,$isOn to pass binding,Medium,https://developer.apple.com/documentation/swiftui/binding
7,State,Use @StateObject for reference types,ObservableObject owned by view,@StateObject for view-created objects,@ObservedObject for owned objects,@StateObject private var vm = ViewModel(),@ObservedObject var vm = ViewModel(),High,https://developer.apple.com/documentation/swiftui/stateobject
8,State,Use @ObservedObject for injected objects,Reference types passed from parent,@ObservedObject for injected dependencies,@StateObject for injected objects,@ObservedObject var vm: ViewModel,@StateObject var vm: ViewModel (injected),High,https://developer.apple.com/documentation/swiftui/observedobject
9,State,Use @EnvironmentObject for shared state,App-wide state injection,@EnvironmentObject for global state,Prop drilling through views,@EnvironmentObject var settings: Settings,Pass settings through 5 views,Medium,https://developer.apple.com/documentation/swiftui/environmentobject
10,State,Use @Published in ObservableObject,Automatically publish property changes,@Published for observed properties,Manual objectWillChange calls,@Published var items: [Item] = [],var items: [Item] { didSet { objectWillChange.send() } },Medium,
11,Observable,Use @Observable macro (iOS 17+),Modern observation without Combine,@Observable class for view models,ObservableObject for new projects,@Observable class ViewModel { },class ViewModel: ObservableObject,Medium,https://developer.apple.com/documentation/observation
12,Observable,Use @Bindable for @Observable,Create bindings from @Observable,@Bindable var vm for bindings,@Binding with @Observable,@Bindable var viewModel,$viewModel.name with @Observable,Medium,
13,Layout,Use VStack HStack ZStack,Standard stack-based layouts,Stacks for linear arrangements,GeometryReader for simple layouts,VStack { Text() Image() },GeometryReader for vertical list,Medium,https://developer.apple.com/documentation/swiftui/vstack
14,Layout,Use LazyVStack LazyHStack for lists,Lazy loading for performance,Lazy stacks for long lists,Regular stacks for 100+ items,LazyVStack { ForEach(items) },VStack { ForEach(largeArray) },High,https://developer.apple.com/documentation/swiftui/lazyvstack
15,Layout,Use GeometryReader sparingly,Only when needed for sizing,GeometryReader for responsive layouts,GeometryReader everywhere,GeometryReader for aspect ratio,GeometryReader wrapping everything,Medium,
16,Layout,Use spacing and padding consistently,Consistent spacing throughout app,Design system spacing values,Magic numbers for spacing,.padding(16) or .padding(),".padding(13), .padding(17)",Low,
17,Layout,Use frame modifiers correctly,Set explicit sizes when needed,.frame(maxWidth: .infinity),Fixed sizes for responsive content,.frame(maxWidth: .infinity),.frame(width: 375),Medium,
18,Modifiers,Order modifiers correctly,Modifier order affects rendering,Background before padding for full coverage,Wrong modifier order,.padding().background(Color.red),.background(Color.red).padding(),High,
19,Modifiers,Create custom ViewModifiers,Reusable modifier combinations,ViewModifier for repeated styling,Duplicate modifier chains,struct CardStyle: ViewModifier,.shadow().cornerRadius() everywhere,Medium,https://developer.apple.com/documentation/swiftui/viewmodifier
20,Modifiers,Use conditional modifiers carefully,Avoid changing view identity,if-else with same view type,Conditional that changes view identity,Text(title).foregroundColor(isActive ? .blue : .gray),if isActive { Text().bold() } else { Text() },Medium,
21,Navigation,Use NavigationStack (iOS 16+),Modern navigation with type-safe paths,NavigationStack with navigationDestination,NavigationView for new projects,NavigationStack { },NavigationView { } (deprecated),Medium,https://developer.apple.com/documentation/swiftui/navigationstack
22,Navigation,Use navigationDestination,Type-safe navigation destinations,.navigationDestination(for:),NavigationLink(destination:),.navigationDestination(for: Item.self),NavigationLink(destination: DetailView()),Medium,
23,Navigation,Use @Environment for dismiss,Programmatic navigation dismissal,@Environment(\.dismiss) var dismiss,presentationMode (deprecated),@Environment(\.dismiss) var dismiss,@Environment(\.presentationMode),Low,
24,Lists,Use List for scrollable content,Built-in scrolling and styling,List for standard scrollable content,ScrollView + VStack for simple lists,List { ForEach(items) { } },ScrollView { VStack { ForEach } },Low,https://developer.apple.com/documentation/swiftui/list
25,Lists,Provide stable identifiers,Use Identifiable or explicit id,Identifiable protocol or id parameter,Index as identifier,ForEach(items) where Item: Identifiable,"ForEach(items.indices, id: \.self)",High,
26,Lists,Use onDelete and onMove,Standard list editing,onDelete for swipe to delete,Custom delete implementation,.onDelete(perform: delete),.onTapGesture for delete,Low,
27,Forms,Use Form for settings,Grouped input controls,Form for settings screens,Manual grouping for forms,Form { Section { Toggle() } },VStack { Toggle() },Low,https://developer.apple.com/documentation/swiftui/form
28,Forms,Use @FocusState for keyboard,Manage keyboard focus,@FocusState for text field focus,Manual first responder handling,@FocusState private var isFocused: Bool,UIKit first responder,Medium,https://developer.apple.com/documentation/swiftui/focusstate
29,Forms,Validate input properly,Show validation feedback,Real-time validation feedback,Submit without validation,TextField with validation state,TextField without error handling,Medium,
30,Async,Use .task for async work,Automatic cancellation on view disappear,.task for view lifecycle async,onAppear with Task,.task { await loadData() },onAppear { Task { await loadData() } },Medium,https://developer.apple.com/documentation/swiftui/view/task(priority:_:)
31,Async,Handle loading states,Show progress during async operations,ProgressView during loading,Empty view during load,if isLoading { ProgressView() },No loading indicator,Medium,
32,Async,Use @MainActor for UI updates,Ensure UI updates on main thread,@MainActor on view models,Manual DispatchQueue.main,@MainActor class ViewModel,DispatchQueue.main.async,Medium,
33,Animation,Use withAnimation,Animate state changes,withAnimation for state transitions,No animation for state changes,withAnimation { isExpanded.toggle() },isExpanded.toggle(),Low,https://developer.apple.com/documentation/swiftui/withanimation(_:_:)
34,Animation,Use .animation modifier,Apply animations to views,.animation(.spring()) on view,Manual animation timing,.animation(.easeInOut),CABasicAnimation equivalent,Low,
35,Animation,Respect reduced motion,Check accessibility settings,Check accessibilityReduceMotion,Ignore motion preferences,@Environment(\.accessibilityReduceMotion),Always animate regardless,High,
36,Preview,Use #Preview macro (Xcode 15+),Modern preview syntax,#Preview for view previews,PreviewProvider protocol,#Preview { ContentView() },struct ContentView_Previews: PreviewProvider,Low,
37,Preview,Create multiple previews,Test different states and devices,Multiple previews for states,Single preview only,"#Preview(""Light"") { } #Preview(""Dark"") { }",Single preview configuration,Low,
38,Preview,Use preview data,Dedicated preview mock data,Static preview data,Production data in previews,Item.preview for preview,Fetch real data in preview,Low,
39,Performance,Avoid expensive body computations,Body should be fast to compute,Precompute in view model,Heavy computation in body,vm.computedValue in body,Complex calculation in body,High,
40,Performance,Use Equatable views,Skip unnecessary view updates,Equatable for complex views,Default equality for all views,struct MyView: View Equatable,No Equatable conformance,Medium,
41,Performance,Profile with Instruments,Measure before optimizing,Use SwiftUI Instruments,Guess at performance issues,Profile with Instruments,Optimize without measuring,Medium,
42,Accessibility,Add accessibility labels,Describe UI elements,.accessibilityLabel for context,Missing labels,".accessibilityLabel(""Close button"")",Button without label,High,https://developer.apple.com/documentation/swiftui/view/accessibilitylabel(_:)-1d7jv
43,Accessibility,Support Dynamic Type,Respect text size preferences,Scalable fonts and layouts,Fixed font sizes,.font(.body) with Dynamic Type,.font(.system(size: 16)),High,
44,Accessibility,Use semantic views,Proper accessibility traits,Correct accessibilityTraits,Wrong semantic meaning,Button for actions Image for display,Image that acts like button,Medium,
45,Testing,Use ViewInspector for testing,Third-party view testing,ViewInspector for unit tests,UI tests only,ViewInspector assertions,Only XCUITest,Medium,
46,Testing,Test view models,Unit test business logic,XCTest for view model,Skip view model testing,Test ViewModel methods,No unit tests,Medium,
47,Testing,Use preview as visual test,Previews catch visual regressions,Multiple preview configurations,No visual verification,Preview different states,Single preview only,Low,
48,Architecture,Use MVVM pattern,Separate view and logic,ViewModel for business logic,Logic in View,ObservableObject ViewModel,@State for complex logic,Medium,
49,Architecture,Keep views dumb,Views display view model state,View reads from ViewModel,Business logic in View,view.items from vm.items,Complex filtering in View,Medium,
50,Architecture,Use dependency injection,Inject dependencies for testing,Initialize with dependencies,Hard-coded dependencies,init(service: ServiceProtocol),let service = RealService(),Medium,