--- name: ios-design description: SwiftUI interface implementation patterns aligned with the iOS 26 / Swift 6.2 clinic modular MVVM-C architecture, grounded in Creative Selection and Design Like Apple principles. Use when building new SwiftUI views/screens while respecting Domain/Data boundaries, App-target route-shell navigation, and production-grade accessibility/interaction standards. --- # Apple SwiftUI iOS Design Best Practices A builder's guide for implementing Apple-quality iOS interfaces in SwiftUI, grounded in two foundational design texts: - **Ken Kocienda** — *Creative Selection* (empathy for the user, craft in coding, taste in choosing the best solution, demo culture of iterative refinement) - **John Edson** — *Design Like Apple* (systems thinking, the product is the marketing, design out loud, design with conviction) Contains 62 rules across 8 principle-based categories. Each rule identifies a specific anti-pattern, grounds the fix in a named principle, and provides the correct iOS 26 / Swift 6.2 SwiftUI implementation. ## Scope & Relationship to Sibling Skills This skill is the **building and implementation guide** — it teaches how to construct new SwiftUI interfaces from scratch using Apple-quality patterns. When loaded alongside `ios-ui-refactor` (reviewing/refactoring existing UI), this skill covers the greenfield implementation that `ios-ui-refactor` later audits. Use this skill for building new screens; use the sibling for evaluating and improving existing ones. ## Clinic Architecture Contract (iOS 26 / Swift 6.2) All guidance in this skill assumes the clinic modular MVVM-C architecture: - Feature modules import `Domain` + `DesignSystem` only (never `Data`, never sibling features) - App target is the convergence point and owns `DependencyContainer`, concrete coordinators, and Route Shell wiring - `Domain` stays pure Swift and defines models plus repository, `*Coordinating`, `ErrorRouting`, and `AppError` contracts - `Data` owns SwiftData/network/sync/retry/background I/O and implements Domain protocols - Read/write flow defaults to stale-while-revalidate reads and optimistic queued writes - ViewModels call repository protocols directly (no default use-case/interactor layer) ## When to Apply Reference these guidelines when: - Building new SwiftUI views and screens from scratch - Choosing between semantic colors, system typography, and spacing grids (Edson's Systems Thinking) - Managing state with @State, @Binding, @Observable, @Environment (Kocienda's Craft) - Selecting the right component: List vs LazyVStack, Sheet vs FullScreenCover (Kocienda's Taste) - Composing views with @ViewBuilder, custom modifiers, and value types (Kocienda's Creative Selection) - Implementing navigation with NavigationStack, TabView, sheets (Edson's Conversation) - Laying out content with stacks, grids, frames, and adaptive layouts (Edson's Design Out Loud) - Ensuring VoiceOver, touch targets, Dark Mode, and reduce motion support (Kocienda's Empathy) - Adding transitions, loading states, and animation polish (Edson's Product Is the Marketing) ## Rule Categories by Priority | Priority | Category | Principle | Impact | Prefix | Rules | |----------|----------|-----------|--------|--------|-------| | 1 | Empathy in Every Pixel | Kocienda "Empathy" · Edson "Design Is About People" | CRITICAL | `empathy-` | 8 | | 2 | The Visual System | Edson "Systems Thinking" · Kocienda "Convergence" | CRITICAL | `system-` | 8 | | 3 | Craft: State as Foundation | Kocienda "Craft" | CRITICAL | `craft-` | 7 | | 4 | Creative Composition | Kocienda "Creative Selection" | HIGH | `compose-` | 6 | | 5 | Taste: The Right Choice | Kocienda "Taste" · Edson "Design with Conviction" | HIGH | `taste-` | 8 | | 6 | Navigation as Conversation | Edson "Design Is a Conversation" · Kocienda "The Demo" | HIGH | `converse-` | 9 | | 7 | Design Out Loud: Layout | Edson "Design Out Loud" · Kocienda "Intersection" | HIGH | `layout-` | 8 | | 8 | The Product Speaks | Edson "Product Is the Marketing" · Kocienda "Demo Culture" | MEDIUM | `product-` | 8 | ## Quick Reference ### 1. Empathy in Every Pixel (CRITICAL) Kocienda: "Empathy — trying to see the world from other people's perspectives." Edson: design begins with the person holding the device. - [`empathy-semantic-colors`](references/empathy-semantic-colors.md) - Use semantic colors, never hard-coded values - [`empathy-dark-mode`](references/empathy-dark-mode.md) - Support Dark Mode from day one - [`empathy-foreground-style`](references/empathy-foreground-style.md) - Use foregroundStyle over foregroundColor - [`empathy-safe-areas`](references/empathy-safe-areas.md) - Always respect safe areas for content - [`empathy-voiceover-labels`](references/empathy-voiceover-labels.md) - Add VoiceOver labels to every interactive element - [`empathy-touch-targets`](references/empathy-touch-targets.md) - Ensure 44x44 point minimum touch targets - [`empathy-reduce-motion`](references/empathy-reduce-motion.md) - Always provide reduce motion fallback - [`empathy-readable-width`](references/empathy-readable-width.md) - Constrain text to readable width on iPad ### 2. The Visual System (CRITICAL) Edson: "Zoom out to see relationships between objects." Kocienda: convergence — many decisions narrowing toward one coherent whole. - [`system-typography`](references/system-typography.md) - Use system typography styles, never fixed sizes - [`system-visual-hierarchy`](references/system-visual-hierarchy.md) - Establish clear visual hierarchy through size, weight, and color - [`system-spacing-grid`](references/system-spacing-grid.md) - Use a 4pt base unit for all spacing - [`system-material-backgrounds`](references/system-material-backgrounds.md) - Use material backgrounds for depth and layering - [`system-sf-symbols`](references/system-sf-symbols.md) - Use SF Symbols for consistent iconography - [`system-gradients`](references/system-gradients.md) - Apply gradients for visual depth, not decoration - [`system-standard-margins`](references/system-standard-margins.md) - Use system standard margins consistently - [`system-stack-config`](references/system-stack-config.md) - Configure stack alignment and spacing explicitly ### 3. Craft: State as Foundation (CRITICAL) Kocienda: "Craft — applying skill to achieve a high-quality result." - [`craft-state-local`](references/craft-state-local.md) - Use @State for view-local value types - [`craft-state-binding`](references/craft-state-binding.md) - Use @Binding for child view mutations - [`craft-state-environment`](references/craft-state-environment.md) - Use @Environment for shared app-wide data - [`craft-state-observable`](references/craft-state-observable.md) - Use @Observable for model classes - [`craft-avoid-body-state`](references/craft-avoid-body-state.md) - Never create state inside the view body - [`craft-minimize-scope`](references/craft-minimize-scope.md) - Minimize state scope to reduce re-renders - [`craft-state-bindable`](references/craft-state-bindable.md) - Use @Bindable for @Observable bindings ### 4. Creative Composition (HIGH) Kocienda: "Creative selection — great software is built through composition and recombination." - [`compose-body-some-view`](references/compose-body-some-view.md) - Return some View from body, never concrete types - [`compose-custom-properties`](references/compose-custom-properties.md) - Use properties to make views configurable - [`compose-modifier-order`](references/compose-modifier-order.md) - Apply view modifiers in the correct order - [`compose-viewbuilder`](references/compose-viewbuilder.md) - Use @ViewBuilder for flexible slot-based composition - [`compose-prefer-value-types`](references/compose-prefer-value-types.md) - Prefer value types for view data - [`compose-prefer-composition`](references/compose-prefer-composition.md) - Prefer composition over inheritance for view reuse ### 5. Taste: The Right Choice (HIGH) Kocienda: "Taste — refined judgment, the ability to choose the one right solution." Edson: commit to one approach and perfect it. - [`taste-list-vs-lazyvstack`](references/taste-list-vs-lazyvstack.md) - Choose List for system features, LazyVStack for custom layouts - [`taste-sheet-vs-fullscreen`](references/taste-sheet-vs-fullscreen.md) - Choose sheet for tasks, fullScreenCover for immersion - [`taste-picker`](references/taste-picker.md) - Choose the right picker style for the data type - [`taste-grid-vs-lazygrid`](references/taste-grid-vs-lazygrid.md) - Choose Grid for aligned data, LazyVGrid for scrollable collections - [`taste-button`](references/taste-button.md) - Use button styles that match the action's importance - [`taste-textfield`](references/taste-textfield.md) - Configure text input with the right keyboard and content type - [`taste-alerts`](references/taste-alerts.md) - Use alerts only for critical, blocking information - [`taste-action-sheets`](references/taste-action-sheets.md) - Use confirmation dialogs for contextual multi-choice actions ### 6. Navigation as Conversation (HIGH) Edson: "Design is a conversation between the product and the person." Kocienda: demos as conversations about whether the interface speaks clearly. - [`converse-navigationstack`](references/converse-navigationstack.md) - Use NavigationStack for programmatic, type-safe navigation - [`converse-tabview`](references/converse-tabview.md) - Organize app sections with TabView for parallel navigation - [`converse-sheet-item`](references/converse-sheet-item.md) - Use item binding for data-driven sheet presentation - [`converse-dismiss`](references/converse-dismiss.md) - Use environment dismiss for modal closure - [`converse-toolbar`](references/converse-toolbar.md) - Place toolbar items in the correct semantic positions - [`converse-tab-bar`](references/converse-tab-bar.md) - Use tab bar for top-level section navigation - [`converse-nav-bar`](references/converse-nav-bar.md) - Configure navigation bar to communicate context - [`converse-hierarchy`](references/converse-hierarchy.md) - Design clear navigation hierarchy before writing code - [`converse-search`](references/converse-search.md) - Integrate search with the searchable modifier ### 7. Design Out Loud: Layout (HIGH) Edson: "Design Out Loud — prototype relentlessly until layout feels inevitable." Kocienda: the intersection of technology and liberal arts. - [`layout-stacks`](references/layout-stacks.md) - Use stacks instead of manual positioning - [`layout-spacer`](references/layout-spacer.md) - Use Spacer for flexible space distribution - [`layout-frame-sizing`](references/layout-frame-sizing.md) - Use frame() for explicit size constraints - [`layout-zstack`](references/layout-zstack.md) - Use ZStack for purposeful layered composition - [`layout-grid`](references/layout-grid.md) - Use Grid for aligned non-scrolling tabular content - [`layout-lazy-grids`](references/layout-lazy-grids.md) - Use LazyVGrid for scrollable multi-column layouts - [`layout-adaptive`](references/layout-adaptive.md) - Use adaptive layouts for different size classes - [`layout-scroll-indicators`](references/layout-scroll-indicators.md) - Show scroll indicators for long scrollable content ### 8. The Product Speaks (MEDIUM) Edson: "The product itself is the marketing." Kocienda: every animation and loading state built to survive Steve Jobs' scrutiny. - [`product-transitions`](references/product-transitions.md) - Use semantic transitions for appearing views - [`product-loading-states`](references/product-loading-states.md) - Show honest loading states, not indefinite spinners - [`product-with-animation`](references/product-with-animation.md) - Use withAnimation for explicit state-driven animation - [`product-matched-geometry`](references/product-matched-geometry.md) - Use matchedGeometryEffect for contextual origin transitions - [`product-list-cells`](references/product-list-cells.md) - Design list cells with standard layouts - [`product-content-unavailable`](references/product-content-unavailable.md) - Use ContentUnavailableView for empty and error states - [`product-segmented`](references/product-segmented.md) - Use segmented controls for visible, mutually exclusive options - [`product-menus`](references/product-menus.md) - Use menus for secondary actions without cluttering the interface ## How to Use Read individual reference files for detailed explanations and code examples: - [Section definitions](references/_sections.md) - Category structure, principle sources, and impact levels - [Rule template](assets/templates/_template.md) - Template for adding new rules ## Reference Files | File | Description | |------|-------------| | [references/_sections.md](references/_sections.md) | Category definitions and principle grounding | | [assets/templates/_template.md](assets/templates/_template.md) | Template for new rules | | [metadata.json](metadata.json) | Version and reference information |