Delivering Rich App Experiences with Haptics

At a glance

Project structure

Source bundle/
├── HapticRicochet-Final/
│   ├── HapticRicochet/
│   │   ├── AppDelegate.swift
│   │   ├── ViewController.swift
│   │   ├── ViewController+Animations.swift
│   │   ├── ViewController+AudioHapticFeedback.swift
│   │   └── ViewController+Motion.swift
│   └── HapticRicochet.xcodeproj/
│       └── .xcodesamplecode.plist
├── HapticRicochet-Start/
│   └── HapticRicochet/
│       ├── AppDelegate.swift
│       ├── ViewController.swift
│       ├── ViewController+Animations.swift
│       ├── ViewController+AudioHapticFeedback.swift
│       └── ViewController+Motion.swift
└── Configuration/
    └── SampleCode.xcconfig

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 11 project/configuration file(s) and 6 source declaration(s).

Overall architecture

flowchart LR
    Bundle["Sample bundle"]
    V1["HapticRicochet-Final"]
    V2["HapticRicochet-Start"]
    Boundary["CoreHaptics APIs"]
    Bundle --> V1
    V1 --> Boundary
    Bundle --> V2
    V2 --> Boundary

Reference code

HapticRicochet-Final/HapticRicochet/AppDelegate.swift:12 — architecture anchor

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        return true
    }

}

Interpretation

The branches represent separate entry-bearing project variants in the downloaded bundle, not runtime calls between those variants. Each branch is intentionally collapsed at the documented framework boundary; the detailed target-local flow remains in the cited files. Ownership is claimed only where the next section cites a stored property or assignment.

Ownership and state

classDiagram
    AppDelegate o-- UIWindow : window
    ViewController o-- UIView : sphereView
    ViewController o-- Cancellable : spherePositionPublisher
    ViewController *-- CGFloat : kSphereRadiusSmall

Ownership evidence

HapticRicochet-Final/HapticRicochet/AppDelegate.swift:15 — stored dependency or nearest verified ownership anchor

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
    // ...
    var window: UIWindow?
    // ...
}

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

HapticRicochet-Final/HapticRicochet/ViewController+Motion.swift:37 — representative execution boundary

            DispatchQueue.main.async {
                self.gravity.gravityDirection = CGVector(dx: gravity.x * 3.5,
                                                         dy: -gravity.y * 3.5)
            }

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

HapticRicochet-Final/HapticRicochet/AppDelegate.swift:13 — representative type boundary

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
    // ...
    var window: UIWindow?
    // ...
}

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

Access control

Reference code

HapticRicochet-Final/HapticRicochet/ViewController+Animations.swift:12 — representative boundary

    private var wallPadding: CGFloat { return 1 }

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: ViewController; Delegate: AppDelegate.
• Protocols: no local protocol declaration in the scanned source.
• Methods: application, viewDidLoad, initializeBackgroundImage, initializeSphere, handleSpherePositionChanged, collisionBehavior, sphereTapped, backgroundTapped.
• Files: HapticRicochet-Final/HapticRicochet/AppDelegate.swift, HapticRicochet-Start/HapticRicochet/AppDelegate.swift, HapticRicochet-Final/HapticRicochet/ViewController.swift, HapticRicochet-Start/HapticRicochet/ViewController.swift.

Architecture takeaways

• AppDelegate is the main source-visible entry or composition anchor for this sample.
• Framework work reaches UIKit, CoreHaptics, CoreMotion, AVFoundation 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