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

Offering media for sale in your app

At a glance

Item Summary
Purpose Allow users to purchase media in the App Store from within your app.
App architecture A C/Objective-C header, Objective-C, Swift sample bundle with entry-bearing project variants Objective-C, Swift, each leading to StoreKit APIs.
Main patterns View-controller organization, Delegate or data-source callbacks
Project style 12 scanned source file(s) across C/Objective-C header, Objective-C, Swift, organized around ranked entry, type, and file boundaries.

Project structure

Source bundle/
├── Objective-C/
│   └── StoreProductViewController/
│       ├── main.m
│       ├── TableViewController.m
│       ├── AppDelegate.h
│       ├── TableViewController.h
│       ├── AppDelegate.m
│       ├── Product.h
│       ├── NSString+Additions.h
│       ├── NSString+Additions.m
│       └── Product.m
└── Swift/
    └── StoreProductViewController/
        ├── AppDelegate.swift
        ├── TableViewController.swift
        └── Product.swift

Structure observations

  • Architecturally prominent files are ranked from entry points and role-named declarations; resource-only paths are omitted.
  • Primary languages: C/Objective-C header, Objective-C, Swift.
  • The verified tree contains 13 project/configuration file(s) and 7 source declaration(s).

Overall architecture

Reference code

Objective-C/StoreProductViewController/main.m:11 — architecture anchor

int main(int argc, char * argv[]) {
    @autoreleasepool {
        return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
    }
}

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

Objective-C/StoreProductViewController/TableViewController.m:15 — stored dependency or nearest verified ownership anchor

@interface TableViewController () <SKStoreProductViewControllerDelegate>
@property (strong) NSMutableArray *products;
@end
Owner Object or state Relationship Mutation authority
TableViewController NSMutableArray (products) retains or copies an assigned value Owning Objective-C implementation
AppDelegate UIWindow (window) retains or copies an assigned value Header-visible collaborators
Product String (title) owns value state App/module collaborators
Product String (productIdentifier) owns value state 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

Swift/StoreProductViewController/AppDelegate.swift:11 — representative type boundary

class AppDelegate: UIResponder, UIApplicationDelegate {
    var window: UIWindow?
}
Type Responsibility Depends on or conforms to
AppDelegate Receives callback-driven events UIResponder, UIApplicationDelegate
AppDelegate Receives callback-driven events UIResponder, UIApplicationDelegate
TableViewController View lifecycle, callbacks, and feature coordination UITableViewController
TableViewController View lifecycle, callbacks, and feature coordination UITableViewController
Product Represents a feature value or composable behavior Concrete collaborators/imported frameworks
Product Defines a feature-specific type boundary NSObject
NSString Defines a feature-specific type boundary 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
window (Objective-C/StoreProductViewController/AppDelegate.h:11) header-visible The declaration is exposed to translation units that import the header. Inference: declare a contract needed by other Objective-C/C translation units.
exists (Objective-C/StoreProductViewController/NSString+Additions.h:13) header-visible The declaration is exposed to translation units that import the header. Inference: declare a contract needed by other Objective-C/C translation units.
title (Objective-C/StoreProductViewController/Product.h:12) header-visible The declaration is exposed to translation units that import the header. Inference: declare a contract needed by other Objective-C/C translation units.
productIdentifier (Objective-C/StoreProductViewController/Product.h:14) header-visible The declaration is exposed to translation units that import the header. Inference: declare a contract needed by other Objective-C/C translation units.

Reference code

Objective-C/StoreProductViewController/AppDelegate.h:11 — representative boundary

@interface AppDelegate : UIResponder <UIApplicationDelegate>
@property (strong, nonatomic) UIWindow *window;
@end

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
View lifecycle, callbacks, and feature coordination TableViewController The source’s Controller suffix makes this role explicit.
Receives callback-driven events AppDelegate The source’s Delegate suffix makes this role explicit.

Design patterns

Pattern Source evidence Purpose or tradeoff
View-controller organization Objective-C/StoreProductViewController/TableViewController.h:11 A controller is the verified coordination boundary; this is MVC-style only where a separate model is present.
Delegate or data-source callbacks Objective-C/StoreProductViewController/AppDelegate.h:10 Callback protocols invert event delivery back into the sample’s owner.

Naming conventions

  • Types: Controller: TableViewController; Delegate: AppDelegate.
  • Protocols: no local protocol declaration in the scanned source.
  • Methods: viewDidLoad, tableView, showStoreForProduct, productViewControllerDidFinish, fetchMedia, showStore, application.
  • Files: Objective-C/StoreProductViewController/TableViewController.m, Objective-C/StoreProductViewController/AppDelegate.h, Objective-C/StoreProductViewController/TableViewController.h, Swift/StoreProductViewController/AppDelegate.swift, Swift/StoreProductViewController/TableViewController.swift, Swift/StoreProductViewController/Product.swift.

Architecture takeaways

  • main is the main source-visible entry or composition anchor for this sample.
  • Framework work reaches UIKit, StoreKit 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
Objective-C/StoreProductViewController/main.m Feature implementation
Objective-C/StoreProductViewController/TableViewController.m TableViewController, TableViewController
Objective-C/StoreProductViewController/AppDelegate.h AppDelegate
Objective-C/StoreProductViewController/TableViewController.h TableViewController
Swift/StoreProductViewController/AppDelegate.swift AppDelegate
Swift/StoreProductViewController/TableViewController.swift TableViewController
Swift/StoreProductViewController/Product.swift Product, CodingKeys
Objective-C/StoreProductViewController/AppDelegate.m AppDelegate
Objective-C/StoreProductViewController/Product.h Product
Objective-C/StoreProductViewController/NSString+Additions.h NSString