Build an Educational Assessment App

At a glance

Project structure

Source bundle/
├── Assessment Time/
│   ├── Swift/
│   │   ├── AppDelegate.swift
│   │   ├── WindowController.swift
│   │   ├── LogViewController.swift
│   │   └── ViewController.swift
│   └── Objective-C/
│       ├── main.m
│       ├── WindowController.m
│       ├── LogViewController.m
│       ├── ViewController.m
│       ├── LogViewController.h
│       ├── ViewController.h
│       └── WindowController.h
└── Assessment Time - SwiftUI.entitlements

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

Overall architecture

flowchart LR
    N1["AppDelegate"]
    N2["LogViewController"]
    N3["AutomaticAssessmentConfiguration APIs"]
    N1 --> N2
    N2 --> N3

Reference code

Assessment Time/Swift/AppDelegate.swift:11 — architecture anchor

@main
@objc(AppDelegate)
class AppDelegate: NSObject, NSApplicationDelegate {

}

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 Automatic Assessment Configuration.

Ownership and state

classDiagram
    WindowController o-- NSToolbarItem : lockUnlockItem
    WindowController o-- NSSegmentedControl : calculatorOptions
    WindowController o-- NSSegmentedControl : dictionaryOptions
    WindowController o-- AEAssessmentSession : session

Ownership evidence

Assessment Time/Objective-C/WindowController.m:11 — stored dependency or nearest verified ownership anchor

@interface WindowController () <AEAssessmentSessionDelegate>
@property (weak) IBOutlet NSToolbarItem *lockUnlockItem;
// ...
@end

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.

Concurrency, scheduling, and thread safety

Evidence limit: actor isolation, async/await, or Task creation does not by itself prove background-thread execution; Sendable conformance alone does not prove thread-safe mutation.

@MainActor/MainActor.run, DispatchQueue.main, and RunLoop.main are reported as distinct isolation, queue, and event-loop mechanisms. A plain Task is kept separate from Task.detached; neither is labeled as a background thread.

Reference code

Assessment Time/Swift/LogViewController.swift:44 — representative execution boundary

        DispatchQueue.main.async {
            self.logTextView.textStorage?.append( NSAttributedString(string: messageWithDate))
            self.logTextView.scrollToEndOfDocument(nil)
        }

State propagation, frameworks, and dependencies

Evidence limit: an import proves a source-level compilation dependency at the cited line; it does not prove runtime use, architectural adoption, or whether a Swift package is a direct application dependency.

receive(on:) describes downstream delivery scheduling, while subscribe(on:) describes upstream subscription/request/cancel scheduling. An import Combine alone establishes neither behavior nor a Store, reducer, Redux, or other application architecture.

Class and protocol design

Assessment Time/Swift/AppDelegate.swift:13 — representative type boundary

@main
@objc(AppDelegate)
class AppDelegate: NSObject, NSApplicationDelegate {

}

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

Access control

Reference code

Assessment Time/Objective-C/LogViewController.m:11 — representative boundary

@interface LogViewController ()
@property (weak) IBOutlet NSTextView *logTextView;
@property (strong) NSDateFormatter *formatter;
@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

Design patterns

Main application flow

sequenceDiagram
    participant WindowController
    participant NSWorkspace
    participant NSWorkspaceOpenConfiguration
    WindowController->>NSWorkspace: URLForApplicationWithBundleIdentifier()
    WindowController->>WindowController: log()
    WindowController->>NSWorkspace: openApplicationAtURL()
    WindowController->>NSWorkspaceOpenConfiguration: completionHandler
    WindowController->>WindowController: log()
    WindowController->>WindowController: log()

Reference code

Assessment Time/Objective-C/WindowController.m:124 — attemptToOpenAppWithBundleID()

- (void) attemptToOpenAppWithBundleID:(NSString *) bundleID {
    NSURL *url = [[NSWorkspace sharedWorkspace] URLForApplicationWithBundleIdentifier:bundleID];
    [self log:@"Attempting to open bundle %@ from %@.", bundleID, url];
    if ( url != NULL ) {
        [[NSWorkspace sharedWorkspace] openApplicationAtURL:url
                                              configuration:[[NSWorkspaceOpenConfiguration alloc] init] completionHandler:^(NSRunningApplication * _Nullable app, NSError * _Nullable error) {
            if ( app != NULL ) {
                [self log:@"App successfully launched."];
            } else {
                [self log:@"App launch error: %@", [error localizedDescription]];
            }
        }];
    }
}

Naming conventions

• Types: Controller: LogViewController, ViewController, WindowController; Delegate: AppDelegate.
• Protocols: no local protocol declaration in the scanned source.
• Methods: lockSession, windowDidLoad, setupAssessmentSession, participantConfiguration, attemptToOpenAppWithBundleID, updateConfiguration, updateLockButton, log.
• Files: Assessment Time/Swift/AppDelegate.swift, Assessment Time/Objective-C/WindowController.m, Assessment Time/Swift/WindowController.swift, Assessment Time/Objective-C/LogViewController.m, Assessment Time/Objective-C/ViewController.m, Assessment Time/Objective-C/LogViewController.h.

Architecture takeaways

• AppDelegate is the main source-visible entry or composition anchor for this sample.
• Framework work reaches Cocoa, AutomaticAssessmentConfiguration, WebKit 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

• Official Apple documentation