swiftui-expert-skill

SwiftUI Expert Skill

Overview

This public intake copy packages plugins/antigravity-awesome-skills-claude/skills/swiftui-expert-skill from https://github.com/sickn33/antigravity-awesome-skills into the native Omni Skills editorial shape without hiding its origin.

Use it when the operator needs the upstream workflow, support files, and repository context to stay intact while the public validator and private enhancer continue their normal downstream flow.

This intake keeps the copied upstream files intact and uses the external_source block in metadata.json plus ORIGIN.md as the provenance anchor for review.

SwiftUI Expert Skill

Imported source sections that did not map cleanly to the public headings are still preserved below or in the support files. Notable imported sections: Review Checklist, Philosophy, Limitations.

When to Use This Skill

Use this section as the trigger filter. It should make the activation boundary explicit before the operator loads files, runs commands, or opens a pull request.

• You are building, reviewing, or refactoring SwiftUI code and need current best practices.
• The task involves state management, view composition, performance, accessibility, or iOS 26+ Liquid Glass adoption.
• You need a fact-based SwiftUI guidance layer without locking into a specific application architecture.
• Use when the request clearly matches the imported source intent: Write, review, or improve SwiftUI code following best practices for state management, view composition, performance, and iOS 26+ Liquid Glass adoption. Use when building new SwiftUI features, refactoring existing....
• Use when the operator should preserve upstream workflow detail instead of rewriting the process from scratch.
• Use when provenance needs to stay visible in the answer, PR, or review packet.

Operating Table

Situation	Start here	Why it matters
First-time use	metadata.json	Confirms repository, branch, commit, and imported path through the external_source block before touching the copied workflow
Provenance review	ORIGIN.md	Gives reviewers a plain-language audit trail for the imported source
Workflow execution	SKILL.md	Starts with the smallest copied file that materially changes execution
Supporting context	SKILL.md	Adds the next most relevant copied source file without loading the entire package
Handoff decision	## Related Skills	Helps the operator switch to a stronger native skill when the task drifts

Workflow

This workflow is intentionally editorial and operational at the same time. It keeps the imported source useful to the operator while still satisfying the public intake standards that feed the downstream enhancer flow.

1. First, consult references/latest-apis.md to ensure only current, non-deprecated APIs are used
2. Check property wrapper usage against the selection guide (see references/state-management.md)
3. Verify view composition follows extraction rules (see references/view-structure.md)
4. Check performance patterns are applied (see references/performance-patterns.md)
5. Verify list patterns use stable identity (see references/list-patterns.md)
6. Check animation patterns for correctness (see references/animation-basics.md, references/animation-transitions.md)
7. Review accessibility: proper grouping, traits, Dynamic Type support (see references/accessibility-patterns.md)

Imported Workflow Notes

Imported: Workflow Decision Tree

1) Review existing SwiftUI code

• First, consult references/latest-apis.md to ensure only current, non-deprecated APIs are used
• Check property wrapper usage against the selection guide (see references/state-management.md)
• Verify view composition follows extraction rules (see references/view-structure.md)
• Check performance patterns are applied (see references/performance-patterns.md)
• Verify list patterns use stable identity (see references/list-patterns.md)
• Check animation patterns for correctness (see references/animation-basics.md, references/animation-transitions.md)
• Review accessibility: proper grouping, traits, Dynamic Type support (see references/accessibility-patterns.md)
• Inspect Liquid Glass usage for correctness and consistency (see references/liquid-glass.md)
• Validate iOS 26+ availability handling with sensible fallbacks

2) Improve existing SwiftUI code

• First, consult references/latest-apis.md to replace any deprecated APIs with their modern equivalents
• Audit state management for correct wrapper selection (see references/state-management.md)
• Extract complex views into separate subviews (see references/view-structure.md)
• Refactor hot paths to minimize redundant state updates (see references/performance-patterns.md)
• Ensure ForEach uses stable identity (see references/list-patterns.md)
• Improve animation patterns (use value parameter, proper transitions, see references/animation-basics.md, references/animation-transitions.md)
• Improve accessibility: use Button over tap gestures, add @ScaledMetric for Dynamic Type (see references/accessibility-patterns.md)
• Suggest image downsampling when UIImage(data:) is used (as optional optimization, see references/image-optimization.md)
• Adopt Liquid Glass only when explicitly requested by the user

3) Implement new SwiftUI feature

• First, consult references/latest-apis.md to use only current, non-deprecated APIs for the target deployment version
• Design data flow first: identify owned vs injected state (see references/state-management.md)
• Structure views for optimal diffing (extract subviews early, see references/view-structure.md)
• Keep business logic in services and models for testability (see references/layout-best-practices.md)
• Use correct animation patterns (implicit vs explicit, transitions, see references/animation-basics.md, references/animation-transitions.md, references/animation-advanced.md)
• Use Button for tappable elements, add accessibility grouping and labels (see references/accessibility-patterns.md)
• Apply glass effects after layout/appearance modifiers (see references/liquid-glass.md)
• Gate iOS 26+ features with #available and provide fallbacks

Imported: Overview

Use this skill to build, review, or improve SwiftUI features with correct state management, optimal view composition, and iOS 26+ Liquid Glass styling. Prioritize native APIs, Apple design guidance, and performance-conscious patterns. This skill focuses on facts and best practices without enforcing specific architectural patterns.

Imported: Review Checklist

Latest APIs (see references/latest-apis.md)

• No deprecated modifiers used (check against the quick lookup table)
• API choices match the project's minimum deployment target

State Management

• @State properties are private
• @Binding only where child modifies parent state
• @StateObject for owned, @ObservedObject for injected
• iOS 17+: @State with @Observable, @Bindable for injected
• Passed values NOT declared as @State or @StateObject
• Nested ObservableObject avoided (or passed directly to child views)

Sheets & Navigation (see references/sheet-navigation-patterns.md)

• Using .sheet(item:) for model-based sheets
• Sheets own their actions and dismiss internally

ScrollView (see references/scroll-patterns.md)

• Using ScrollViewReader with stable IDs for programmatic scrolling

View Structure (see references/view-structure.md)

• Using modifiers instead of conditionals for state changes
• Complex views extracted to separate subviews
• Container views use @ViewBuilder let content: Content

Performance (see references/performance-patterns.md)

• View body kept simple and pure (no side effects)
• Passing only needed values (not large config objects)
• Eliminating unnecessary dependencies
• State updates check for value changes before assigning
• Hot paths minimize state updates
• No object creation in body
• Heavy computation moved out of body

List Patterns (see references/list-patterns.md)

• ForEach uses stable identity (not .indices)
• Constant number of views per ForEach element
• No inline filtering in ForEach
• No AnyView in list rows

Layout (see references/layout-best-practices.md)

• Avoiding layout thrash (deep hierarchies, excessive GeometryReader)
• Gating frequent geometry updates by thresholds
• Business logic kept in services and models (not in views)
• Action handlers reference methods (not inline logic)
• Using relative layout (not hard-coded constants)
• Views work in any context (context-agnostic)

Animations (see references/animation-basics.md, references/animation-transitions.md, references/animation-advanced.md)

• Using .animation(_:value:) with value parameter
• Using withAnimation for event-driven animations
• Transitions paired with animations outside conditional structure
• Custom Animatable has explicit animatableData implementation
• Preferring transforms over layout changes for animation performance
• Phase animations for multi-step sequences (iOS 17+)
• Keyframe animations for precise timing (iOS 17+)
• Completion handlers use .transaction(value:) for reexecution

Accessibility (see references/accessibility-patterns.md)

• Button used instead of onTapGesture for tappable elements
• @ScaledMetric used for custom values that should scale with Dynamic Type
• Related elements grouped with accessibilityElement(children:)
• Custom controls use accessibilityRepresentation when appropriate

Liquid Glass (iOS 26+)

• #available(iOS 26, *) with fallback for Liquid Glass
• Multiple glass views wrapped in GlassEffectContainer
• .glassEffect() applied after layout/appearance modifiers
• .interactive() only on user-interactable elements
• Shapes and tints consistent across related elements

Examples

Example 1: Ask for the upstream workflow directly

Use @swiftui-expert-skill to handle <task>. Start from the copied upstream workflow, load only the files that change the outcome, and keep provenance visible in the answer.

Explanation: This is the safest starting point when the operator needs the imported workflow, but not the entire repository.

Example 2: Ask for a provenance-grounded review

Review @swiftui-expert-skill against metadata.json and ORIGIN.md, then explain which copied upstream files you would load first and why.

Explanation: Use this before review or troubleshooting when you need a precise, auditable explanation of origin and file selection.

Example 3: Narrow the copied support files before execution

Use @swiftui-expert-skill for <task>. Load only the copied references, examples, or scripts that change the outcome, and name the files explicitly before proceeding.

Explanation: This keeps the skill aligned with progressive disclosure instead of loading the whole copied package by default.

Example 4: Build a reviewer packet

Review @swiftui-expert-skill using the copied upstream files plus provenance, then summarize any gaps before merge.

Explanation: This is useful when the PR is waiting for human review and you want a repeatable audit packet.

Best Practices

Treat the generated public skill as a reviewable packaging layer around the upstream repository. The goal is to keep provenance explicit and load only the copied source material that materially improves execution.

• @State must be private; use for internal view state
• @Binding only when a child needs to modify parent state
• @StateObject when view creates the object; @ObservedObject when injected
• iOS 17+: Use @State with @Observable classes; use @Bindable for injected observables needing bindings
• Use let for read-only values; var + .onChange() for reactive reads
• Never pass values into @State or @StateObject — they only accept initial values
• Nested ObservableObject doesn't propagate changes — pass nested objects directly; @Observable handles nesting fine

Imported Operating Notes

Imported: Core Guidelines

State Management

• @State must be private; use for internal view state
• @Binding only when a child needs to modify parent state
• @StateObject when view creates the object; @ObservedObject when injected
• iOS 17+: Use @State with @Observable classes; use @Bindable for injected observables needing bindings
• Use let for read-only values; var + .onChange() for reactive reads
• Never pass values into @State or @StateObject — they only accept initial values
• Nested ObservableObject doesn't propagate changes — pass nested objects directly; @Observable handles nesting fine

View Composition

• Extract complex views into separate subviews for better readability and performance
• Prefer modifiers over conditional views for state changes (maintains view identity)
• Keep view body simple and pure (no side effects or complex logic)
• Use @ViewBuilder functions only for small, simple sections
• Prefer @ViewBuilder let content: Content over closure-based content properties
• Keep business logic in services and models; views should orchestrate UI flow
• Action handlers should reference methods, not contain inline logic
• Views should work in any context (don't assume screen size or presentation style)

Performance

• Pass only needed values to views (avoid large "config" or "context" objects)
• Eliminate unnecessary dependencies to reduce update fan-out
• Check for value changes before assigning state in hot paths
• Avoid redundant state updates in onReceive, onChange, scroll handlers
• Minimize work in frequently executed code paths
• Use LazyVStack/LazyHStack for large lists
• Use stable identity for ForEach (never .indices for dynamic content)
• Ensure constant number of views per ForEach element
• Avoid inline filtering in ForEach (prefilter and cache)
• Avoid AnyView in list rows
• Consider POD views for fast diffing (or wrap expensive views in POD parents)
• Suggest image downsampling when UIImage(data:) is encountered (as optional optimization)
• Avoid layout thrash (deep hierarchies, excessive GeometryReader)
• Gate frequent geometry updates by thresholds
• Use Self._logChanges() or Self._printChanges() to debug unexpected view updates

Animations

• Use .animation(_:value:) with value parameter (deprecated version without value is too broad)
• Use withAnimation for event-driven animations (button taps, gestures)
• Prefer transforms (offset, scale, rotation) over layout changes (frame) for performance
• Transitions require animations outside the conditional structure
• Custom Animatable implementations must have explicit animatableData
• Use .phaseAnimator for multi-step sequences (iOS 17+)
• Use .keyframeAnimator for precise timing control (iOS 17+)
• Animation completion handlers need .transaction(value:) for reexecution
• Implicit animations override explicit animations (later in view tree wins)

Accessibility

• Prefer Button over onTapGesture for tappable elements (free VoiceOver support)
• Use @ScaledMetric for custom numeric values that should scale with Dynamic Type
• Group related elements with accessibilityElement(children: .combine) for joined labels
• Provide accessibilityLabel when default labels are unclear or missing
• Use accessibilityRepresentation for custom controls that should behave like native ones

Liquid Glass (iOS 26+)

Only adopt when explicitly requested by the user.

• Use native glassEffect, GlassEffectContainer, and glass button styles
• Wrap multiple glass elements in GlassEffectContainer
• Apply .glassEffect() after layout and visual modifiers
• Use .interactive() only for tappable/focusable elements
• Use glassEffectID with @Namespace for morphing transitions

Troubleshooting

Problem: The operator skipped the imported context and answered too generically

Symptoms: The result ignores the upstream workflow in plugins/antigravity-awesome-skills-claude/skills/swiftui-expert-skill, fails to mention provenance, or does not use any copied source files at all. Solution: Re-open metadata.json, ORIGIN.md, and the most relevant copied upstream files. Check the external_source block first, then restate the provenance before continuing.

Problem: The imported workflow feels incomplete during review

Symptoms: Reviewers can see the generated SKILL.md, but they cannot quickly tell which references, examples, or scripts matter for the current task. Solution: Point at the exact copied references, examples, scripts, or assets that justify the path you took. If the gap is still real, record it in the PR instead of hiding it.

Problem: The task drifted into a different specialization

Symptoms: The imported skill starts in the right place, but the work turns into debugging, architecture, design, security, or release orchestration that a native skill handles better. Solution: Use the related skills section to hand off deliberately. Keep the imported provenance visible so the next skill inherits the right context instead of starting blind.

Related Skills

• @00-andruia-consultant - Use when the work is better handled by that native specialization after this imported skill establishes context.
• @00-andruia-consultant-v2 - Use when the work is better handled by that native specialization after this imported skill establishes context.
• @10-andruia-skill-smith - Use when the work is better handled by that native specialization after this imported skill establishes context.
• @10-andruia-skill-smith-v2 - Use when the work is better handled by that native specialization after this imported skill establishes context.

Additional Resources

Use this support matrix and the linked files below as the operator packet for this imported skill. They should reflect real copied source material, not generic scaffolding.

Resource family	What it gives the reviewer	Example path
references	copied reference notes, guides, or background material from upstream	references/n/a
examples	worked examples or reusable prompts copied from upstream	examples/n/a
scripts	upstream helper scripts that change execution or validation	scripts/n/a
agents	routing or delegation notes that are genuinely part of the imported package	agents/n/a
assets	supporting assets or schemas copied from the source package	assets/n/a

Imported Reference Notes

Imported: Quick Reference

Property Wrapper Selection

Wrapper	Use When
@State	Internal view state (must be private)
@Binding	Child modifies parent's state
@StateObject	View owns an ObservableObject
@ObservedObject	View receives an ObservableObject
@Bindable	iOS 17+: Injected @Observable needing bindings
let	Read-only value from parent
var	Read-only value watched via .onChange()

Liquid Glass Patterns

// Basic glass effect with fallback
if #available(iOS 26, *) {
    content
        .padding()
        .glassEffect(.regular.interactive(), in: .rect(cornerRadius: 16))
} else {
    content
        .padding()
        .background(.ultraThinMaterial, in: RoundedRectangle(cornerRadius: 16))
}

// Grouped glass elements
GlassEffectContainer(spacing: 24) {
    HStack(spacing: 24) {
        GlassButton1()
        GlassButton2()
    }
}

// Glass buttons
Button("Confirm") { }
    .buttonStyle(.glassProminent)

Imported: References

• references/latest-apis.md - Required reading for all workflows. Version-segmented guide of deprecated-to-modern API transitions (iOS 15+ through iOS 26+)
• references/state-management.md - Property wrappers and data flow
• references/view-structure.md - View composition, extraction, and container patterns
• references/performance-patterns.md - Performance optimization techniques and anti-patterns
• references/list-patterns.md - ForEach identity, stability, and list best practices
• references/layout-best-practices.md - Layout patterns, context-agnostic views, and testability
• references/accessibility-patterns.md - Accessibility traits, grouping, Dynamic Type, and VoiceOver
• references/animation-basics.md - Core animation concepts, implicit/explicit animations, timing, performance
• references/animation-transitions.md - Transitions, custom transitions, Animatable protocol
• references/animation-advanced.md - Transactions, phase/keyframe animations (iOS 17+), completion handlers (iOS 17+)
• references/sheet-navigation-patterns.md - Sheet presentation and navigation patterns
• references/scroll-patterns.md - ScrollView patterns and programmatic scrolling
• references/image-optimization.md - AsyncImage, image downsampling, and optimization
• references/liquid-glass.md - iOS 26+ Liquid Glass API

Imported: Philosophy

This skill focuses on facts and best practices, not architectural opinions:

• We don't enforce specific architectures (e.g., MVVM, VIPER)
• We do encourage separating business logic for testability
• We optimize for performance and maintainability
• We follow Apple's Human Interface Guidelines and API design patterns

Imported: Limitations

• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.