Tracking geographic locations in AR

At a glance

Project structure

Source bundle/
├── GeoTrackingExample/
│   ├── AppDelegate.swift
│   ├── ViewController.swift
│   ├── Utilities.swift
│   ├── GPXParser.swift
│   ├── GPXExporter.swift
│   ├── GeoAnchorWithAssociatedData.swift
│   ├── ViewController+CoachingOverlay.swift
│   ├── ViewController+LoadSaveAnchors.swift
│   └── Base.lproj/
│       └── LaunchScreen.storyboard
├── Configuration/
│   └── SampleCode.xcconfig
└── GeoTrackingExample.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 7 source declaration(s).

Overall architecture

flowchart LR
    N1["AppDelegate"]
    N2["ViewController"]
    N3["ARKit APIs"]
    N1 --> N2
    N2 --> N3

Reference code

GeoTrackingExample/AppDelegate.swift:11 — architecture anchor

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

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 ARKit.

Ownership and state

classDiagram
    AppDelegate o-- UIWindow : window
    ViewController o-- ARView : arView
    ViewController o-- MKMapView : mapView
    ViewController o-- UILabel : toastLabel

Ownership evidence

GeoTrackingExample/AppDelegate.swift:14 — 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.

Class and protocol design

GeoTrackingExample/GPXParser.swift:10 — representative type boundary

protocol GPXParserDelegate: AnyObject {
    func parser(_ parser: GPXParser, didFinishParsingFileWithAnchors anchors: [ARGeoAnchor])
}

The source explicitly defines local protocol relationships: ViewController → GPXParserDelegate.

Access control

Reference code

GeoTrackingExample/GPXExporter.swift:14 — representative boundary

class GPXExporter {
    // ...
}

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, GPXParserDelegate.
• Protocols: GPXParserDelegate.
• Methods: application, viewDidLoad, viewDidAppear, viewDidDisappear, menuButtonTapped, handleTapOnARView, handleTapOnMapView, undoButtonTapped.
• Files: GeoTrackingExample/AppDelegate.swift, GeoTrackingExample/ViewController.swift, GeoTrackingExample/GPXParser.swift, GeoTrackingExample/GPXExporter.swift, GeoTrackingExample/GeoAnchorWithAssociatedData.swift.

Architecture takeaways

• AppDelegate is the main source-visible entry or composition anchor for this sample.
• Framework work reaches ARKit, UIKit, MapKit, RealityKit 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.
• Local protocol relationships provide an explicit substitution boundary.

Source map

• Official Apple documentation