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

Wishlist: Planning travel in a SwiftUI app

At a glance

Item Summary
Purpose Build a travel planning app that organizes trips into collections and tracks activity completion.
App architecture A Swift sample bundle with entry-bearing project variants WithSwiftData, WithoutPersistence, each leading to SwiftUI APIs.
Main patterns Delegate or data-source callbacks, Binding-based state propagation
Project style 43 scanned source file(s) across Swift, organized around ranked entry, type, and file boundaries.

Project structure

Source bundle/
├── WithSwiftData/
│   └── Wishlist/
│       ├── WishlistApp.swift
│       └── Views/
│           ├── Trips/
│           │   ├── AddTripView.swift
│           │   └── TripCollectionView.swift
│           ├── SearchView.swift
│           └── Goals/
│               └── GoalsView.swift
└── WithoutPersistence/
    └── Wishlist/
        ├── WishlistApp.swift
        ├── Views/
        │   ├── Trips/
        │   │   ├── AddTripView.swift
        │   │   └── TripCollectionView.swift
        │   ├── SearchView.swift
        │   └── Goals/
        │       └── GoalsView.swift
        └── Models/
            ├── DataSource.swift
            └── TripEditModel.swift

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 7 project/configuration file(s) and 84 source declaration(s).

Overall architecture

Reference code

WithSwiftData/Wishlist/WishlistApp.swift:11 — architecture anchor

@main
struct WishlistApp: App {
    // ...
}

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

Ownership evidence

WithSwiftData/Wishlist/Views/SearchView.swift:52 — stored dependency or nearest verified ownership anchor

private struct SearchResultsListView: View {
    // ...
    @Query(sort: \Trip.name) private var trips: [Trip]
    // ...
}
Owner Object or state Relationship Mutation authority
SearchResultsListView Array (trips) owns value state Owning lexical scope
SearchResultsListView Array (activities) owns value state Owning lexical scope
SearchResultsListView String (searchText) owns value state App/module collaborators
SearchResultsListView ID (namespace) stores or receives App/module collaborators

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

WithSwiftData/Wishlist/WishlistApp.swift:12 — representative type boundary

struct WishlistApp: App {
    // ...
}
Type Responsibility Depends on or conforms to
WishlistApp Application entry and top-level composition App
WishlistApp Application entry and top-level composition App
AddTripView User-interface presentation and input forwarding View
Model Feature data or observable state Concrete collaborators/imported frameworks
AddTripView User-interface presentation and input forwarding View
Model Feature data or observable state Concrete collaborators/imported frameworks
SearchView User-interface presentation and input forwarding View
SearchResultsListView User-interface presentation and input forwarding View
SearchItemView User-interface presentation and input forwarding View
TripSearchSectionView User-interface presentation and input forwarding View

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
ordinalModifier (WithSwiftData/Wishlist/Models/Goal.swift:56) fileprivate Use is restricted to this source file. Inference: share with same-file helpers or extensions without exposing the symbol module-wide.
allTrips (WithSwiftData/Wishlist/Models/SampleData.swift:58) 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.
allTripGoals (WithSwiftData/Wishlist/Models/SampleData.swift:182) 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.
allActivityGoals (WithSwiftData/Wishlist/Models/SampleData.swift:200) 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

WithSwiftData/Wishlist/Models/Goal.swift:56 — representative boundary

    fileprivate var ordinalModifier: String {
        target == 1 ? "first" : "\(target.ordinal)"
    }

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 WishlistApp The source’s App suffix makes this role explicit.
Supplies data through a callback contract DataSource The source’s DataSource suffix makes this role explicit.
Feature data or observable state Model, TripEditModel The source’s Model suffix makes this role explicit.
User-interface presentation and input forwarding ActivityItemView, ActivityProgressView, ActivitySearchSectionView, AddTripView The source’s View suffix makes this role explicit.

Design patterns

Pattern Source evidence Purpose or tradeoff
Delegate or data-source callbacks WithoutPersistence/Wishlist/Models/DataSource.swift:16 Callback protocols invert event delivery back into the sample’s owner.
Binding-based state propagation WithSwiftData/Wishlist/Views/Trips/ActivitySection.swift:15 A binding exposes controlled read/write access while the upstream owner remains authoritative.

Naming conventions

  • Types: App: WishlistApp; DataSource: DataSource; Model: Model, TripEditModel; View: ActivityItemView, ActivityProgressView, ActivitySearchSectionView, AddTripView, ContentView.
  • Protocols: no local protocol declaration in the scanned source.
  • Methods: saveImageToTemporaryDirectory, addTrip.
  • Files: WithSwiftData/Wishlist/WishlistApp.swift, WithoutPersistence/Wishlist/WishlistApp.swift, WithSwiftData/Wishlist/Views/Trips/AddTripView.swift, WithoutPersistence/Wishlist/Views/Trips/AddTripView.swift, WithSwiftData/Wishlist/Views/SearchView.swift, WithoutPersistence/Wishlist/Views/SearchView.swift.

Architecture takeaways

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

Source file Relevant symbols
WithSwiftData/Wishlist/WishlistApp.swift WishlistApp
WithoutPersistence/Wishlist/WishlistApp.swift WishlistApp
WithSwiftData/Wishlist/Views/Trips/AddTripView.swift AddTripView, TripImagePicker, TripDetailsForm, TripTitleField, TripGroupPicker, Model
WithoutPersistence/Wishlist/Views/Trips/AddTripView.swift AddTripView, TripImagePicker, TripDetailsForm, TripTitleField, TripGroupPicker, Model
WithSwiftData/Wishlist/Views/SearchView.swift SearchView, SearchResultsListView, SearchItemView, TripSearchSectionView, ActivitySearchSectionView
WithoutPersistence/Wishlist/Views/SearchView.swift SearchView, SearchResultsListView, SearchSection, SearchItemView, SearchSectionView
WithSwiftData/Wishlist/Views/Goals/GoalsView.swift GoalsView, AchievedGoalTile, GoalTile
WithSwiftData/Wishlist/Views/Trips/TripCollectionView.swift TripCollectionView, TripCard, Size
WithoutPersistence/Wishlist/Views/Goals/GoalsView.swift GoalsView, AchievedGoalTile, GoalTile
WithoutPersistence/Wishlist/Views/Trips/TripCollectionView.swift TripCollectionView, TripCard, Size