swiftui-core

Covers SwiftUI fundamentals shared across all Apple platforms: composable views and modifiers, navigation (NavigationStack for stack-based flows, NavigationSplitView for multi-column layouts), data persistence with SwiftData (@Model, replacing Core Data for most cases), state management (@State for local, @Observable for shared, @Environment for injection), Liquid Glass styling, and App Intents for Siri/Shortcuts integration.

References cover views/modifiers, navigation, SwiftData, state management, Liquid Glass across platforms, and App Intents in depth, plus Apple Human Interface Guidelines (HIG) rules with source URLs: accessibility (Dynamic Type to AX5, VoiceOver, contrast, hit targets, Reduce Motion/Transparency), right-to-left, modality/sheets/alerts/onboarding, system surfaces (widgets, Live Activities, notifications, App Shortcuts/Siri/snippets), and iPhone Duo.

Visual specs come from the design-ios handoff when one exists; this skill implements and verifies them. Best practices: extract subviews once a view body mixes responsibilities or stops reading at a glance, compose with ViewBuilder and modifiers, always include #Preview, use system colors (custom colors need light, dark and increased-contrast variants), label every icon-only control, and adapt layout by size class.

SwiftUI Core

SwiftUI fundamentals shared across all Apple platforms.

Agent Workflow (MANDATORY)

Before ANY implementation, spawn 3 agents in parallel, one Agent call each with a name:

1. fuse-ai-pilot:explore-codebase - Analyze existing SwiftUI patterns
2. fuse-ai-pilot:research-expert - Verify latest SwiftUI docs via Context7/Exa
3. mcp__apple-docs__search_apple_docs - Check SwiftUI view patterns

After implementation, run fuse-ai-pilot:sniper for validation.

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Overview

When to Use

• Building SwiftUI views and components
• Implementing navigation (NavigationStack, SplitView)
• Data persistence with SwiftData
• State management (@State, @Observable)
• Custom view modifiers and layouts

Why SwiftUI Core

Feature	Benefit
Declarative UI	Less code, automatic updates
Cross-platform	Same code for iOS/macOS/watchOS/visionOS
@Observable	Simple reactive state
SwiftData	Modern persistence with minimal code

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Key Concepts

Views & Modifiers

Composable UI building blocks. Extract subviews at 30+ lines.

Navigation

NavigationStack for stack-based, NavigationSplitView for multi-column.

SwiftData

Modern persistence with @Model. Replaces Core Data for most use cases.

State Management

@State for local, @Observable for shared, @Environment for injection.

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Reference Guide

Need	Reference
Views, modifiers, layouts	views-modifiers.md
NavigationStack, deep linking	navigation.md
SwiftData, @Query, CloudKit	data-swiftdata.md
@State, @Observable, Environment	state-management.md
Liquid Glass all platforms	liquid-glass.md
Siri, Shortcuts, App Intents	app-intents.md

HIG Rules (load for any UI task)

Need	Reference
Dynamic Type AX5, VoiceOver, contrast, targets, Reduce Motion	hig-accessibility.md
Arabic/Hebrew mirroring, numerals	hig-rtl.md
Sheets, alerts, modality, onboarding, launch, permissions	hig-modality.md
Widgets, Live Activities, notifications, App Shortcuts, Siri, snippets	hig-system-surfaces.md
iPhone Duo (foldable), reserved regions, vertical toolbars	hig-iphone-duo.md

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Best Practices

1. Small views - Extract at 30+ lines
2. Composition - Use ViewBuilder and modifiers
3. Preview-driven - Always include #Preview
4. System colors - Custom colors ship light, dark and increased-contrast variants (HIG color)
5. Accessibility - Label icon-only controls, layout survives AX5, targets >= 44 pt on iOS (hig-accessibility.md)
6. Platform adaptation - Size classes, never fixed widths or device checks (HIG layout)