uikit-expert

UIKit Expert Skill

Overview

Use this skill to build, review, or improve UIKit features with correct lifecycle management, performant Auto Layout, modern collection view APIs, and safe navigation patterns. Prioritize native APIs, Apple's documented best practices, and performance-conscious patterns. This skill focuses on facts and best practices without enforcing specific architectural patterns (no MVVM/VIPER/Coordinator mandates).

Workflow Decision Tree

1) Review existing UIKit code

• Check view controller lifecycle usage — viewIsAppearing for geometry, viewDidLoad for setup only (see references/view-controller-lifecycle.md)
• Verify Auto Layout correctness — batch activation, no constraint churn, translatesAutoresizingMaskIntoConstraints (see references/auto-layout.md)
• Check collection/table view APIs — diffable data sources, stable identity, CellRegistration (see references/modern-collection-views.md)
• Verify cell configuration uses UIContentConfiguration, not deprecated textLabel (see references/cell-configuration.md)
• Check list scroll performance — prefetching, cell reuse cleanup, reconfigureItems (see references/list-performance.md)
• Verify navigation patterns — bar appearance all 4 slots, no concurrent transition crashes (see references/navigation-patterns.md)
• Check animation correctness — API selection, PropertyAnimator state machine, constraint animation (see references/animation-patterns.md)
• Audit memory management — [weak self], delegate ownership, Timer/CADisplayLink traps (see references/memory-management.md)
• Check concurrency safety — Task lifecycle, cancellation in viewDidDisappear (see references/concurrency-main-thread.md)
• If SwiftUI interop present — verify UIHostingController containment, sizingOptions (see references/uikit-swiftui-interop.md)
• Check image loading — downsampling, cell reuse race condition (cancel/clear/verify) (see references/image-loading.md)
• Verify keyboard handling — UIKeyboardLayoutGuide over manual notifications (see references/keyboard-scroll.md)
• Check trait handling and accessibility — registerForTraitChanges, Dynamic Type, VoiceOver (see references/adaptive-appearance.md)
• Validate modern API adoption and iOS 26+ availability handling (see references/modern-uikit-apis.md)