AgentSkillsCN

iOS Dependency Injection

在基于协议的依赖注入、属性包装器以及工厂/针剂模式方面的规范。

SKILL.md
--- frontmatter
name: iOS Dependency Injection
description: Standards for Protocol-based DI, Property Wrappers, and Factory/Needle.
metadata:
  labels: [ios, di, dependency-injection, injection, modularity]
  triggers:
    files: ['**/*.swift']
    keywords: [@Injected, Resolver, Container, Swinject, register, resolve]

iOS Dependency Injection Standards

Priority: P0

Implementation Guidelines

Protocol-Based DI (Manual)

  • •Initializer Injection: Preferred method. Pass dependencies through init.
  • •Abstractions: Inject protocols instead of concrete classes to facilitate testing (Mocks/Stubs).

Modern Property Wrappers (Factory/Resolver)

  • •Factory: Use the Factory library for lightweight, type-safe navigation-friendly DI.
  • •Swinject: Use for enterprise-grade container-based DI in large modular projects.
  • •Injected: Use @Injected property wrappers for cleaner syntax in ViewModels.

Scoping

  • •Singleton: Use for app-wide services (Auth, Network, Database).
  • •Unique/Transient: Default for ViewModels and temporary workers.
  • •Graph/Cached: Use for shared data within a specific feature flow (Coordinator scope).

Anti-Patterns

  • •Singletitis: **No global Shared singleton access everywhere**: Inject the service via initializer.
  • •Service Locator: **No Resolver.resolve() inside logic**: Pass dependency via constructor or property wrapper.
  • •Concrete Dependency: **No direct class instantiation**: Depend on protocols for testability.

References