Sample CodeiOS, iPadOS, Mac Catalyst, macOSReviewed 2026-07-21View on Apple Developer

Implementing a virtual conference extension

At a glance

Item Summary
Purpose Support adding a virtual conference room to an event in Calendar.
App architecture A Swift sample with the source-visible chain VirtualConferenceSampleAppContentViewVirtualConferenceProviderEventKit APIs.
Main patterns No named application pattern supported by the extracted structure
Project style 3 scanned source file(s) across Swift, organized around ranked entry, type, and file boundaries.

Project structure

Source bundle/
├── VirtualConferenceSampleApp/
│   ├── VirtualConferenceSampleApp.swift
│   └── ContentView.swift
├── VirtualConferenceSampleExtension/
│   ├── VirtualConferenceProvider.swift
│   └── Info.plist
├── Configuration/
│   └── SampleCode.xcconfig
└── VirtualConferenceSampleApp.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 4 project/configuration file(s) and 4 source declaration(s).

Overall architecture

Reference code

VirtualConferenceSampleApp/VirtualConferenceSampleApp.swift:10 — architecture anchor

@main
struct VirtualConferenceSampleApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

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 EventKit.

Ownership and state

Ownership evidence

VirtualConferenceSampleExtension/VirtualConferenceProvider.swift:8 — stored dependency or nearest verified ownership anchor

import EventKit
Owner Object or state Relationship Mutation authority
VirtualConferenceSampleApp EventKit APIs Uses framework types; no stored lifecycle relationship was detected in the architecture anchor. The declaring implementation controls calls.

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

VirtualConferenceSampleApp/VirtualConferenceSampleApp.swift:11 — representative type boundary

struct VirtualConferenceSampleApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}
Type Responsibility Depends on or conforms to
VirtualConferenceSampleApp Application entry and top-level composition App
VirtualConferenceProvider Supplies a capability or framework resource EKVirtualConferenceProvider
ContentView User-interface presentation and input forwarding View
VirtualConferenceSampleError Represents feature failure conditions Error

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

Access control

Symbol Access Verified effect Likely rationale
message (VirtualConferenceSampleApp/ContentView.swift:11) private Use is restricted to the lexical declaration and same-file extensions allowed by Swift. Inference: keep state mutation or dependency lifetime inside the owning implementation.

Reference code

VirtualConferenceSampleApp/ContentView.swift:11 — representative boundary

    private var message: String {
        // ...
    }

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

Logic Owning type or file Placement rationale
Application entry and top-level composition VirtualConferenceSampleApp The source’s App suffix makes this role explicit.
Supplies a capability or framework resource VirtualConferenceProvider The source’s Provider suffix makes this role explicit.
User-interface presentation and input forwarding ContentView The source’s View suffix makes this role explicit.

Design patterns

Pattern Source evidence Purpose or tradeoff
No named application pattern VirtualConferenceSampleApp/VirtualConferenceSampleApp.swift:10 The verified source directly composes concrete framework types; this document avoids forcing a pattern name.

Naming conventions

  • Types: App: VirtualConferenceSampleApp; Provider: VirtualConferenceProvider; View: ContentView.
  • Protocols: no local protocol declaration in the scanned source.
  • Methods: fetchAvailableRoomTypes, fetchVirtualConference, createVirtualConferenceDescriptor.
  • Files: VirtualConferenceSampleApp/VirtualConferenceSampleApp.swift, VirtualConferenceSampleExtension/VirtualConferenceProvider.swift, VirtualConferenceSampleApp/ContentView.swift.

Architecture takeaways

  • VirtualConferenceSampleApp is the main source-visible entry or composition anchor for this sample.
  • Framework work reaches SwiftUI, EventKit 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

Source file Relevant symbols
VirtualConferenceSampleApp/VirtualConferenceSampleApp.swift VirtualConferenceSampleApp
VirtualConferenceSampleExtension/VirtualConferenceProvider.swift VirtualConferenceProvider, VirtualConferenceSampleError
VirtualConferenceSampleApp/ContentView.swift ContentView