Sample CodemacOSReviewed 2026-07-21View on Apple Developer

Encrypting and Decrypting Directories

At a glance

Item Summary
Purpose Compress and encrypt the contents of an entire directory or decompress and decrypt an archived directory using Apple Encrypted Archive.
App architecture A Swift sample with the source-visible chain DirectoryEncryptionDecryptionAppContentViewAppleArchive APIs.
Main patterns Delegate or data-source callbacks
Project style 3 scanned source file(s) across Swift, organized around ranked entry, type, and file boundaries.

Project structure

Source bundle/
├── DirectoryEncryptionDecryption/
│   ├── DirectoryEncryptionDecryptionApp.swift
│   ├── ContentView.swift
│   └── ArchiverEncryptor.swift
├── Configuration/
│   └── SampleCode.xcconfig
└── DirectoryEncryptionDecryption.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 3 project/configuration file(s) and 7 source declaration(s).

Overall architecture

Reference code

DirectoryEncryptionDecryption/DirectoryEncryptionDecryptionApp.swift:10 — architecture anchor

@main
struct DirectoryEncryptionDecryptionApp: 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 Apple Archive.

Ownership and state

Ownership evidence

DirectoryEncryptionDecryption/ContentView.swift:42 — stored dependency or nearest verified ownership anchor

struct DirectoryDropDelegate: DropDelegate {
    // ...
    var consoleMessages: Binding<[ConsoleMessage]>
    // ...
}
Owner Object or state Relationship Mutation authority
DirectoryDropDelegate Binding (consoleMessages) stores or receives App/module collaborators
DirectoryDropDelegate Binding (mode) stores or receives App/module collaborators
ContentView String (base64EncodedKeyData) owns wrapper-managed state Owning lexical scope
ContentView Array (consoleMessages) owns wrapper-managed state Owning lexical scope

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

DirectoryEncryptionDecryption/DirectoryEncryptionDecryptionApp.swift:11 — representative type boundary

struct DirectoryEncryptionDecryptionApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}
Type Responsibility Depends on or conforms to
DirectoryEncryptionDecryptionApp Application entry and top-level composition App
DirectoryDropDelegate Receives callback-driven events DropDelegate
ContentView User-interface presentation and input forwarding View
Mode Defines a closed set of feature states or choices Equatable
ConsoleMessage Represents a feature value or composable behavior Identifiable, Equatable
Status Defines a closed set of feature states or choices Concrete collaborators/imported frameworks
ArchiverEncryptor Represents a feature value or composable behavior Concrete collaborators/imported frameworks

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
base64EncodedKeyData (DirectoryEncryptionDecryption/ContentView.swift:103) 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.
mode (DirectoryEncryptionDecryption/ContentView.swift:104) 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.
consoleMessages (DirectoryEncryptionDecryption/ContentView.swift:105) 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.
ArchiverEncryptor (DirectoryEncryptionDecryption/ArchiverEncryptor.swift:9) implicit internal No explicit modifier means the Swift declaration is internal to the module. Inference: app-target collaboration needs no exported library surface.

Reference code

DirectoryEncryptionDecryption/ContentView.swift:103 — representative boundary

    @State private var base64EncodedKeyData: String = ""
    @State private var mode = Mode.idle
    @State private var consoleMessages: [ConsoleMessage] = [
        ConsoleMessage(status: .info,
                       message: "Apple Archive Demo App")]

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 DirectoryEncryptionDecryptionApp The source’s App suffix makes this role explicit.
Receives callback-driven events DirectoryDropDelegate The source’s Delegate 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
Delegate or data-source callbacks DirectoryEncryptionDecryption/ContentView.swift:38 Callback protocols invert event delivery back into the sample’s owner.

Naming conventions

  • Types: App: DirectoryEncryptionDecryptionApp; Delegate: DirectoryDropDelegate; View: ContentView.
  • Protocols: no local protocol declaration in the scanned source.
  • Methods: performDrop, addConsoleMessage, submitBase64EncodedKeyData, copyToPasteboard, encrypt, decrypt.
  • Files: DirectoryEncryptionDecryption/DirectoryEncryptionDecryptionApp.swift, DirectoryEncryptionDecryption/ContentView.swift, DirectoryEncryptionDecryption/ArchiverEncryptor.swift.

Architecture takeaways

  • DirectoryEncryptionDecryptionApp is the main source-visible entry or composition anchor for this sample.
  • Framework work reaches CryptoKit, SwiftUI, AppKit, AppleArchive 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
DirectoryEncryptionDecryption/DirectoryEncryptionDecryptionApp.swift DirectoryEncryptionDecryptionApp
DirectoryEncryptionDecryption/ContentView.swift Mode, DirectoryDropDelegate, ContentView, ContentView_Previews
DirectoryEncryptionDecryption/ArchiverEncryptor.swift ConsoleMessage, Status, ArchiverEncryptor