ios-ui-navigation

name	ios-ui-navigation
description	Implement UIKit navigation, Auto Layout, and Apple Human Interface Guidelines in iOS. Use when implementing UIKit navigation, Auto Layout constraints, or HIG compliance.
metadata	{"triggers":{"files":["**/*View.swift","**/*.xib","**/*.storyboard"],"keywords":["NSLayoutConstraint","UIStackView","SnapKit","layoutSubviews"]}}

iOS UI & Layout Standards

Priority: P0 (CRITICAL)

Implementation Guidelines

Auto Layout

• Code-Based Layout: Prefer programmatic layout using NSLayoutAnchor or SnapKit over Storyboards for better source control.
• Safe Area: Always respect view.safeAreaLayoutGuide.
• UIStackView: Use for linear layouts to reduce constraint complexity.

UIKit Best Practices

• View Lifecycle: Perform layout adjustments in viewWillLayoutSubviews or updateConstraints.
• Reusable Views: Extract complex UI into custom UIView subclasses.
• Image Optimization: Use SF Symbols for icons. Preferred vector (PDF/SVG) for custom assets.
• SwiftUI Bridge: Use UIViewRepresentable or UIViewControllerRepresentable to host UIKit in SwiftUI.

Human Interface Guidelines (HIG)

• Accessibility: Support Dynamic Type and provide meaningful accessibilityLabel.
• Feedback: Use UINotificationFeedbackGenerator for haptic feedback on actions.
• Margins: Follow standard system margins (typically 16-20pt).

Anti-Patterns

• No CGRect(x:y:w:h): Use Auto Layout.
• No complex constraint logic in VC: Use UIStackView or custom views.
• No Blank Screens: Use skeleton views or UIActivityIndicatorView.

References

• Auto Layout & HIG Compliance

Canonical response anchors

When this skill applies, preserve the following domain terminology or equivalent concrete examples in the answer when relevant:

• UIViewControllerRepresentable
• UIViewRepresentable

Remediation anchors

• Remediation anchors: NSLayoutAnchor, safeAreaLayoutGuide, UIStackView