Series Recap: What We've Covered

We've covered a lot of ground. Here's a quick reference of everything in this series.

Follow along with the code: iOS-Practice on GitHub

Concurrency Deep Dive

GCD & Threading

• Race conditions and serial queues
• Thread-safe collections
• Main thread violations
• DispatchQueue.main vs @MainActor
• Deadlocks: sync to same queue
• Lock ordering

Async/Await

• Task cancellation (cooperative)
• Debounced search
• Actor reentrancy
• Safe financial systems with actors
• Unstructured task leaks
• Structured vs unstructured concurrency

Combine

• Retain cycles with [weak self]
• Timer subscriptions
• Missing cancellables
• Multiple subscription management

Testing Mastery

Dependency Injection

• Refactoring singletons
• Protocol-based DI
• Decoupling network code
• Mock HTTP clients
• Testing time-dependent code
• DateProviding pattern

Side Effects

• Testing UserDefaults
• InMemoryKeyValueStore
• Abstracting file system
• In-memory file systems

Architecture & Mocking

• Testing ViewModels with @Published
• Repository pattern
• Mock vs Stub vs Fake vs Spy
• Spy mocks for interaction verification
• Testable service layers

Async Testing

• Testing async/await methods
• Testing TaskGroup operations
• Cache behavior testing
• Actor isolation in tests

SwiftUI Patterns

Lists & Data Loading

• Loading and error states
• ContentUnavailableView
• Pull-to-refresh
• Relative dates
• Search with debouncing
• Multi-filter lists

Grids & Layouts

• LazyVGrid photo galleries
• Sheet-based detail views
• Adaptive grids
• Grid/list mode transitions

Navigation

• NavigationStack master-detail
• Value-based NavigationLink
• Modal presentations
• Confirmation dialogs
• Swipe actions
• Passing data from modals

State Management

• Form validation
• Password strength indicators
• @StateObject vs @ObservedObject
• Shopping cart with EnvironmentObject

Key Patterns Summary

What's Next

The final two posts cover setting up the practice projects and resources for continued learning.