ios-uikit

name	ios-uikit
description	This skill MUST be invoked when the user says "UIKit", "iOS geliştirme", "programmatic UI", "table view", "collection view", "Auto Layout", "UIViewController", "UINavigationController", "Core Animation", "UIKit review", "UIKit build", "iOS view controller", "UIKit pattern", "programmatic layout", or any variation requesting UIKit development, review, or improvement. Covers programmatic UIKit with Auto Layout, table/collection views, navigation, animation, networking, architecture, and 20 reference documents with production-ready patterns.
argument-hint	[review | build | improve]

Programmatic UIKit Development

Build, review, and improve programmatic UIKit applications following production-ready patterns. All UI is built in code — no Storyboards.

Usage

/ios-uikit review     # Review existing UIKit code for issues
/ios-uikit build      # Implement new UIKit feature
/ios-uikit improve    # Modernize existing UIKit code
/ios-uikit            # Auto-detect mode from context

Operating Rules

• All UI built programmatically. Always set translatesAutoresizingMaskIntoConstraints = false.
• Prefer NSLayoutConstraint.activate([...]) for batch constraint activation.
• Organize view controller code with extensions: separate style(), layout(), and protocol conformances.
• Use factory functions for repetitive UI element creation.
• Use weak references for delegates and [weak self] in closures to prevent retain cycles.
• Prefer async/await for new code; Result<Success, Error> for completion handler APIs.
• Always dispatch UI updates to the main thread — use @MainActor or MainActor.run {}.
• Extract custom views flush to their container; parent manages spacing.
• Use child view controllers for complex, self-contained screen sections.
• Consult relevant reference files before implementing any topic.

Modes

Review Mode (/ios-uikit review)

1. Read the code under review and identify which topics apply
2. Run the Topic Router below for each relevant topic
3. Check for retain cycles (missing weak delegates, missing [weak self])
4. Verify Auto Layout completeness (unambiguous constraints, no warnings)
5. Flag deprecated patterns (e.g., manual beginUpdates/endUpdates when Diffable is available)
6. Check for missing @MainActor on UI-updating async code
7. Flag completion handler patterns where async/await would be cleaner

Build Mode (/ios-uikit build)

1. Design data flow first: identify service, view model, view controller, and view layers
2. Structure views for composition (extracted views + child view controllers)
3. Apply correct animation patterns (constraint-based, Core Animation, or UIView)
4. Use protocol-delegate for sustained relationships; closures for one-shot callbacks
5. Add proper loading/error states
6. Include accessibility identifiers and VoiceOver support

Improve Mode (/ios-uikit improve)

1. Audit current implementation against the Topic Router topics
2. Extract large view controllers into child VCs and custom views
3. Replace inline UI creation with factory functions
4. Migrate legacy table/collection view data sources to Diffable where appropriate
5. Migrate completion handlers to async/await where possible
6. Add @MainActor annotations to ViewModel and UI-updating code
7. Add proper error handling with Result types or throws

Topic Router

Consult the reference file for each topic relevant to the current task:

Topic	Reference
UITableView	references/uitableview.md
UICollectionView	references/uicollectionview.md
UINavigationController	references/uinavigationcontroller.md
UIScrollView	references/uiscrollview.md
Core Animation	references/core-animation.md
Core Graphics	references/core-graphics.md
Auto Layout Animation	references/auto-layout-animation.md
Communication Patterns	references/communication-patterns.md
Architecture Patterns	references/architecture-patterns.md
View Extraction	references/view-extraction.md
Navigation Patterns	references/navigation-patterns.md
Design Patterns (UI)	references/design-patterns.md
Networking	references/networking.md
Factory Functions	references/factory-patterns.md
Nib / XIB Patterns	references/nib-patterns.md
NSAttributedString	references/nsattributedstring.md
Gesture Recognizers	references/gesture-recognizers.md
Custom Controls	references/custom-controls.md
Currency Formatting	references/currency-formatting.md
Deep Linking	references/deep-linking.md

Correctness Checklist

Hard rules — violations are always bugs:

Layout

• Every programmatic view sets translatesAutoresizingMaskIntoConstraints = false
• NSLayoutConstraint.activate() is used instead of isActive = true one-by-one
• Factory functions return views with translatesAutoresizingMaskIntoConstraints already false
• Custom views define intrinsicContentSize when they have a natural size

Memory

• Delegates are declared weak var delegate: SomeDelegate?
• Async closures capture [weak self] when referencing the owning object
• Combine subscriptions stored in Set<AnyCancellable> with store(in:)

Table / Collection Views

• performBatchUpdates used (not beginUpdates/endUpdates) for iOS 11+
• Diffable data source items conform to Hashable with stable identifiers
• Cell registration uses UICollectionView.CellRegistration or register(_:forCellWithReuseIdentifier:)

Threading

• UI updates from async callbacks dispatched to DispatchQueue.main or use @MainActor
• async functions that update UI are marked @MainActor
• Core Data background work uses performBackgroundTask or perform

Child View Controllers

• Follow 3-step lifecycle: addChild(), addSubview(), didMove(toParent:)
• Removal: willMove(toParent: nil), removeFromSuperview(), removeFromParent()

Animation

• Core Animation model layer updated after animation to persist final state
• Bounds-dependent layers (shadows, gradients) set in viewDidLayoutSubviews

Networking

• Prefer async/await URLSession APIs for new code
• Completion handler APIs use Result<T, Error> return type
• Network tasks stored for cancellation support

Quick Diagnostics

Symptom	Likely Cause	Reference
View doesn't appear	Missing translatesAutoresizingMaskIntoConstraints = false	references/view-extraction.md
Table view crashes on insert	Data source count mismatch with batch updates	references/uitableview.md
Animation snaps to final state	Model layer not updated after CA animation	references/core-animation.md
Retain cycle / memory leak	Missing weak on delegate or [weak self]	references/communication-patterns.md
Scroll view doesn't scroll	Missing content size or broken constraint chain	references/uiscrollview.md
Shadow clipped by view	masksToBounds = true on layer	references/core-animation.md
Gradient/shadow wrong size	Set bounds-dependent layers in viewDidLayoutSubviews	references/core-animation.md
Collection view empty	Forgot to register cell or data source nil	references/uicollectionview.md
Core Data threading crash	Accessing managed object on wrong queue	references/networking.md
Nav bar title missing	Not setting title or navigationItem.title	references/uinavigationcontroller.md
Async callback UI freeze	Missing @MainActor or DispatchQueue.main dispatch	references/architecture-patterns.md
Combine subscription no fire	Subscriber deallocated — store in cancellables	references/communication-patterns.md

Modern Swift Notes

When working with UIKit in modern Swift (2025+):

• async/await is preferred over completion handlers for new networking code
• @MainActor replaces manual DispatchQueue.main.async for UI thread safety
• Combine is available for reactive data binding (alternative to delegate/closure patterns)
• Diffable Data Source is the standard for table/collection view data management
• UICollectionViewCompositionalLayout replaces manual flow layout calculations
• UIViewPropertyAnimator provides interruptible, scrubbable animations
• Completion handlers remain valid for existing codebases — do not force-migrate without reason