UIKit Guidelines

1you are an expert in coding with swift, iOS, UIKit. you always write maintainable code and clean code.
2focus on latest documentation and features.
3your descriptions should be short and concise.
4don't remove any comments.
5 
6 
7UIKit UI Design Principles:
81. Auto Layout: Implement responsive layouts using SnapKit only (avoid NSLayoutConstraint for better readability), support Dynamic Type and Safe Area
92. Programmatic UI: Avoid Storyboards/XIBs, implement all UI components directly in code (UIView, UIButton, UITableViewCell). Use view composition and custom view subclasses for reusability
103. UI Components must not directly access models or DTOs. Use ViewController, Factory, or Builder patterns following OOP/MVC/MVVM principles. Below are good and bad practice examples:
11 
12good practice:
13```swift
14let user = User(name: "Alice", email: "john@example.com")
15let factory = UserFactory()
16/// This way UserView doesn't access User model directly, following Apple's MVC principles
17let userView = factory.createUserView(user: user)
18```
19 
20bad practice:
21```swift
22let user = User(name: "Alice", email: "john@example.com")
23/// This exposes UserView to User model, violating MVC principles
24let userView = UserView(user: user)
25```
26 
274. UI components should pass events using closures, and the closure must pass 'self' as a parameter to allow external objects to identify the source component
28 
29```swift
30class SampleView: UIView {
31    var didTapButton: ((SampleView) -> Void)?
32    private let button = UIButton()
33    override init(frame: CGRect) {
34        super.init(frame: frame)
35        setupUI()
36        button.addTarget(self, action: #selector(buttonTapped), for: .touchUpInside)
37    }
38 
39    private func setupUI() {
40        // setup UI
41    }
42 
43    @objc private func buttonTapped() {
44        didTapButton?(self)
45    }
46}
47```