Adopting menus and UIActions in your user interface

At a glance

Project structure

Source bundle/
├── ControlMenus/
│   ├── AppDelegate.swift
│   ├── SegmentedControlDemoViewController.swift
│   ├── BarButtonItemDemoViewController.swift
│   ├── ButtonMenuDemoViewController.swift
│   ├── DeferredMenuElementDemoViewController.swift
│   ├── SceneDelegate.swift
│   ├── UpdateMenuViewController.swift
│   ├── ViewController.swift
│   └── CustomMenuControl.swift
├── Configuration/
│   └── SampleCode.xcconfig
└── ControlMenus.xcodeproj/
    ├── .xcodesamplecode.plist
    └── project.pbxproj

Structure observations

• Architecturally prominent files are ranked from entry points and role-named declarations; resource-only paths are omitted.
• Primary languages: Swift.
• The verified tree contains 6 project/configuration file(s) and 11 source declaration(s).

Overall architecture

flowchart LR
    N1["AppDelegate"]
    N2["BarButtonItemDemoViewController"]
    N3["UIKit APIs"]
    N1 --> N2
    N2 --> N3

Reference code

ControlMenus/AppDelegate.swift:10 — architecture anchor

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.
        return true
    }

    // MARK: UISceneSession Lifecycle

    func application(_ application: UIApplication,
                     configurationForConnecting connectingSceneSession: UISceneSession,
                     options: UIScene.ConnectionOptions) -> UISceneConfiguration {
        /** Called when a new scene session is being created.
            Use this method to select a configuration to create the new scene with.
        */
        return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
    }

    func application(_ application: UIApplication,
                     didDiscardSceneSessions sceneSessions: Set<UISceneSession>) {
        /** Called when the user discards a scene session.
            If any sessions were discarded while the application was not running,
            this will be called shortly after application:didFinishLaunchingWithOptions.
            Use this method to release any resources that were specific to the discarded scenes, as they will not return.
        */
    }

}

Interpretation

The arrows summarize the source-visible entry, role-named types or folders, and framework direction; when nodes come from structural folders, the sequence is a high-level interpretation rather than proof that every adjacent node calls the next. Ownership is claimed only where the next section cites a stored property or assignment. The diagram is intentionally limited to the dominant path into UIKit.

Ownership and state

classDiagram
    BarButtonItemDemoViewController *-- UILabel : eventExplainer
    BarButtonItemDemoViewController o-- Title : title
    BarButtonItemDemoViewController o-- Toolbaritems : toolbarItems
    ButtonMenuDemoViewController *-- UILabel : eventExplainer

Ownership evidence

ControlMenus/BarButtonItemDemoViewController.swift:13 — stored dependency or nearest verified ownership anchor

class BarButtonItemDemoViewController: UIViewController {
    // ...
    let eventExplainer = UILabel()
    // ...
}

Composition arrows indicate a source-visible construction expression or locally owned value state; aggregation means the owner stores or receives a dependency without proving exclusive lifetime ownership.

Concurrency, scheduling, and thread safety

Evidence limit: actor isolation, async/await, or Task creation does not by itself prove background-thread execution; Sendable conformance alone does not prove thread-safe mutation.

@MainActor/MainActor.run, DispatchQueue.main, and RunLoop.main are reported as distinct isolation, queue, and event-loop mechanisms. A plain Task is kept separate from Task.detached; neither is labeled as a background thread.

Reference code

ControlMenus/DeferredMenuElementDemoViewController.swift:22 — representative execution boundary

                DispatchQueue.main.asyncAfter(deadline: .now() + 2.0) {
                    let items = (1...2).map { UIAction(title: "Dynamic Item \($0)") { action in } }
                    completion([UIMenu(title: "", options: .displayInline, children: items)])
                }

State propagation, frameworks, and dependencies

Evidence limit: an import proves a source-level compilation dependency at the cited line; it does not prove runtime use, architectural adoption, or whether a Swift package is a direct application dependency.

receive(on:) describes downstream delivery scheduling, while subscribe(on:) describes upstream subscription/request/cancel scheduling. An import Combine alone establishes neither behavior nor a Store, reducer, Redux, or other application architecture.

Class and protocol design

ControlMenus/AppDelegate.swift:11 — representative type boundary

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
    // ...
        return true
    // ...
}

No local protocol conformance is claimed as protocol-oriented design; external framework conformances are listed only as dependencies.

Access control

Reference code

ControlMenus/CustomMenuControl.swift:54 — representative boundary

    private lazy var titleLabel: UILabel = {
        let label = UILabel()
        // ...
    }()

Swift declarations without a modifier are internal; explicit private, fileprivate, private(set), public, or open entries above are interpreted by language semantics. Objective-C/C samples instead rely on header and implementation boundaries, which are not equivalent to Swift lexical privacy.

Logic ownership and placement

Design patterns

Naming conventions

• Types: Controller: BarButtonItemDemoViewController, ButtonMenuDemoViewController, DeferredMenuElementDemoViewController, SegmentedControlDemoViewController, UpdateMenuViewController; Delegate: AppDelegate, SceneDelegate.
• Protocols: no local protocol declaration in the scanned source.
• Methods: application, color, image, viewDidLoad, showExplainer, menuHandler, viewWillAppear, scene.
• Files: ControlMenus/AppDelegate.swift, ControlMenus/SegmentedControlDemoViewController.swift, ControlMenus/BarButtonItemDemoViewController.swift, ControlMenus/ButtonMenuDemoViewController.swift, ControlMenus/DeferredMenuElementDemoViewController.swift, ControlMenus/SceneDelegate.swift.

Architecture takeaways

• AppDelegate is the main source-visible entry or composition anchor for this sample.
• Framework work reaches UIKit through a deliberately small high-level chain; the detailed API graph remains inside the cited implementation files.
• Stored-property evidence identifies lifecycle collaboration; it does not by itself prove exclusive object ownership.
• Access-control conclusions separate verified language visibility from the likely design rationale.
• The source does not justify labeling the design protocol-oriented.

Source map

• Official Apple documentation