Extracted the in-app notifications from the Sample app target into its own Notifying package target.

Apps/Attendi/Models/AppNotification.swift

@@ -1,73 +0,0 @@
-import Foundation
-
-/// An in-app notification reporting an event of a speech model asset download.
-struct AppNotification: Equatable, Identifiable {
-
-    // MARK: Properties
-
-    /// The unique identifier of the notification.
-    let id: UUID
-
-    /// The download event the notification reports.
-    let event: Event
-
-    /// The localized name of the locale whose speech model the event is about.
-    let localeName: String
-
-    // MARK: Initializers
-
-    /// Creates a notification for a given download event and locale name.
-    ///
-    /// - Parameters:
-    ///   - id: The unique identifier of the notification. Defaults to a newly generated identifier.
-    ///   - event: The download event the notification reports.
-    ///   - localeName: The localized name of the locale whose speech model the event is about.
-    init(
-        id: UUID = .init(),
-        event: Event,
-        localeName: String
-    ) {
-        self.id = id
-        self.event = event
-        self.localeName = localeName
-    }
-
-}
-
-// MARK: - Enumerations
-
-extension AppNotification {
-    /// The download event the notification reports.
-    enum Event: Sendable {
-        /// The download was cancelled before it finished.
-        case cancelled
-        /// The download failed.
-        case failed
-        /// The download started.
-        case started
-    }
-}
-
-// MARK: - Properties
-
-extension AppNotification {
-    
-    /// The system symbol of the icon matching the notification's event.
-    var imageSymbol: String {
-        switch event {
-        case .cancelled: "xmark.circle"
-        case .failed: "exclamationmark.triangle"
-        case .started: "arrow.down.circle"
-        }
-    }
-
-    /// The localized message of the notification, naming the locale of the speech model, from the app's string catalog.
-    var textMessage: LocalizedStringResource {
-        switch event {
-        case .cancelled: .viewRecordingNotificationDownloadCancelled(localeName)
-        case .failed: .viewRecordingNotificationDownloadFailed(localeName)
-        case .started: .viewRecordingNotificationDownloadStarted(localeName)
-        }
-    }
-
-}

Attendi.xcodeproj/project.pbxproj

@@ -24,10 +24,8 @@
 				Attendi/App/AttendiApp.swift,
 				Attendi/Catalogs/Assets.xcassets,
 				Attendi/Catalogs/Localizable.xcstrings,
-				Attendi/Models/AppNotification.swift,
 				"Attendi/View Models/ContentViewModel.swift",
 				Attendi/Views/ContentView.swift,
-				Styles/Labels/NotificationLabelStyle.swift,
 			);
 			target = 02870A0C2FF7EB610079EA3A /* Attendi */;
 		};

Packages/Features/Package.swift

@@ -13,14 +13,26 @@ let package = Package(
     products: [
         .library(
             name: "Features",
-            targets: ["Recording"]
+            targets: [
+                "Notifying",
+                "Recording",
+            ]
         ),
     ],
     targets: [
+        .target(
+            name: "Notifying",
+            path: "Sources/Notifying"
+        ),
         .target(
             name: "Recording",
             path: "Sources/Recording"
         ),
+        .testTarget(
+            name: "NotifyingTests",
+            dependencies: ["Notifying"],
+            path: "Tests/Notifying"
+        ),
         .testTarget(
             name: "RecordingTests",
             dependencies: ["Recording"],

Packages/Features/Sources/Notifying/Models/AppNotification.swift

@@ -0,0 +1,55 @@
+import Foundation
+
+/// A transient in-app notification, posted and dismissed by a ``Notifier``.
+public struct AppNotification: Equatable, Identifiable, Sendable {
+
+    // MARK: Properties
+
+    /// The unique identifier of the notification.
+    public let id: UUID
+
+    /// The kind of the notification, driving its visual weight.
+    public let kind: Kind
+
+    /// The localized message of the notification.
+    public let message: String
+
+    /// The system symbol of the notification's icon.
+    public let symbol: String
+
+    // MARK: Initializers
+
+    /// Creates a notification of a given kind, with a localized message and a system symbol.
+    ///
+    /// - Parameters:
+    ///   - id: The unique identifier of the notification. Defaults to a newly generated identifier.
+    ///   - kind: The kind of the notification.
+    ///   - message: The localized message of the notification.
+    ///   - symbol: The system symbol of the notification's icon.
+    public init(
+        id: UUID = .init(),
+        kind: Kind,
+        message: String,
+        symbol: String
+    ) {
+        self.id = id
+        self.kind = kind
+        self.message = message
+        self.symbol = symbol
+    }
+
+}
+
+// MARK: - Enumerations
+
+extension AppNotification {
+    /// The kind of a notification, driving its visual weight.
+    public enum Kind: Sendable {
+        /// The notification reports an error.
+        case error
+        /// The notification reports an informational event.
+        case info
+        /// The notification reports a warning.
+        case warning
+    }
+}

Packages/Features/Sources/Notifying/Styles/Labels/NotificationLabelStyle.swift

@@ -3,24 +3,24 @@ import SwiftUI
 /// The label style for the transient in-app notification banners.
 ///
 /// The style renders the label's icon next to its title, over a padded, capsule Liquid Glass background. The icon is tinted with a color
-/// matching the download event given at initialization — green for a started download, yellow for a cancelled one, and red for a
+/// matching the kind of notification given at initialization — green for an informational one, yellow for a warning, and red for an
-/// failed one — and the title wears a medium-weight callout font.
+/// error — and the title wears a medium-weight callout font.
-struct NotificationLabelStyle: LabelStyle {
+public struct NotificationLabelStyle: LabelStyle {
 
     // MARK: Properties
 
-    /// The download event whose matching color tints the label's icon.
+    /// The kind of notification whose matching color tints the label's icon.
-    private let event: AppNotification.Event
+    private let kind: AppNotification.Kind
 
     // MARK: Initializers
 
-    /// Creates a notification label style for a given download event.
+    /// Creates a notification label style for a given kind of notification.
     ///
-    /// - Parameter event: The download event whose matching color tints the label's icon.
+    /// - Parameter kind: The kind of notification whose matching color tints the label's icon.
-    fileprivate init(
+    public init(
-        event: AppNotification.Event
+        kind: AppNotification.Kind
     ) {
-        self.event = event
+        self.kind = kind
     }
 
     // MARK: Methods
@@ -36,7 +36,7 @@ struct NotificationLabelStyle: LabelStyle {
         ) {
             configuration.icon
                 .font(.title3)
-                .foregroundStyle(event.imageStyle)
+                .foregroundStyle(kind.imageStyle)
 
             configuration.title
                 .font(.callout)
@@ -55,37 +55,36 @@ struct NotificationLabelStyle: LabelStyle {
 
 // MARK: - Styles
 
-extension LabelStyle where Self == NotificationLabelStyle {
+public extension LabelStyle where Self == NotificationLabelStyle {
 
     /// The label style for the transient in-app notification banners.
     ///
-    /// - Parameter event: The download event whose matching color tints the label's icon.
+    /// - Parameter kind: The kind of notification whose matching color tints the label's icon.
-    /// - Returns: A notification label style for the given event.
+    /// - Returns: A notification label style for the given kind of notification.
     static func notification(
-        event: AppNotification.Event
+        kind: AppNotification.Kind
     ) -> NotificationLabelStyle {
-        .init(event: event)
+        .init(kind: kind)
     }
 
 }
 
-// MARK: - AppNotification.Event+Properties
+// MARK: - AppNotification.Kind+Properties
 
-private extension AppNotification.Event {
+private extension AppNotification.Kind {
 
-    /// The color that tints the icon of a notification label: green for a started download, yellow for a cancelled one, and red
+    /// The color that tints the icon of a notification label: green for an informational notification, yellow for a warning, and red
-    /// for a failed one.
+    /// for an error.
     var imageStyle: Color {
         switch self {
-        case .cancelled: .yellow
+        case .error: .red
-        case .failed: .red
+        case .info: .green
-        case .started: .green
+        case .warning: .yellow
         }
     }
 
 }
 
-
 // MARK: - Constants
 
 /// The constant values used across the label style.
@@ -120,7 +119,7 @@ private enum Constant {
             Image(systemName: "arrow.down.circle")
         }
         .labelStyle(.notification(
-                event: .started
+            kind: .info
         ))
 
         Label {
@@ -129,7 +128,7 @@ private enum Constant {
             Image(systemName: "xmark.circle")
         }
         .labelStyle(.notification(
-            event: .cancelled
+            kind: .warning
         ))
 
         Label {
@@ -138,8 +137,7 @@ private enum Constant {
             Image(systemName: "exclamationmark.triangle")
         }
         .labelStyle(.notification(
-            event: .failed
+            kind: .error
         ))
     }
-    
 }

Packages/Features/Sources/Notifying/View Models/Notifier.swift

@@ -0,0 +1,65 @@
+import Accessibility
+import Foundation
+import Observation
+
+/// The observable model that owns the lifecycle of the transient in-app notifications.
+///
+/// Posting a notification appends it to ``notifications``, announces its message to assistive technologies — since the visual
+/// banners are transient — and schedules its automatic dismissal a few seconds later, which is the only way a notification is
+/// dismissed.
+@MainActor
+@Observable
+public final class Notifier {
+
+    // MARK: Properties
+
+    /// The notifications currently presented, in post order.
+    public private(set) var notifications: [AppNotification] = []
+
+    /// The time a posted notification stays visible before its automatic dismissal.
+    @ObservationIgnored
+    private let delayDismissal: Duration
+
+    // MARK: Initializers
+
+    /// Creates a notifier.
+    ///
+    /// - Parameter delayDismissal: The time a posted notification stays visible before its automatic dismissal.
+    /// Defaults to four seconds.
+    public init(
+        delayDismissal: Duration = .seconds(4)
+    ) {
+        self.delayDismissal = delayDismissal
+    }
+
+    // MARK: Methods
+
+    /// Posts a notification, announcing its message to assistive technologies and scheduling its automatic dismissal.
+    ///
+    /// - Parameters:
+    ///   - kind: The kind of the notification.
+    ///   - message: The localized message of the notification.
+    ///   - symbol: The system symbol of the notification's icon.
+    public func post(
+        _ kind: AppNotification.Kind,
+        message: String,
+        symbol: String
+    ) {
+        let notification = AppNotification(
+            kind: kind,
+            message: message,
+            symbol: symbol
+        )
+
+        notifications.append(notification)
+
+        AccessibilityNotification.Announcement(message).post()
+
+        Task {
+            try? await Task.sleep(for: delayDismissal)
+
+            notifications.removeAll { $0.id == notification.id }
+        }
+    }
+
+}

Packages/Features/Tests/Features.xctestplan

@@ -18,6 +18,13 @@
         "identifier" : "RecordingTests",
         "name" : "RecordingTests"
       }
+    },
+    {
+      "target" : {
+        "containerPath" : "container:",
+        "identifier" : "NotifyingTests",
+        "name" : "NotifyingTests"
+      }
     }
   ],
   "version" : 1

Packages/Features/Tests/Notifying/View Models/NotifierTests.swift

@@ -0,0 +1,110 @@
+import Foundation
+import Testing
+
+@testable import Notifying
+
+@Suite("Notifier view model")
+struct NotifierTests {
+
+    // MARK: Posting
+
+    @MainActor
+    @Suite("Posting")
+    struct Posting {
+
+        @Test func `posting appends a notification with the given values`() {
+            let notifier = Notifier()
+
+            notifier.post(
+                .info,
+                message: "This is a notification.",
+                symbol: "info.circle"
+            )
+
+            #expect(notifier.notifications.count == 1)
+            #expect(notifier.notifications.first?.kind == .info)
+            #expect(notifier.notifications.first?.message == "This is a notification.")
+            #expect(notifier.notifications.first?.symbol == "info.circle")
+        }
+
+        @Test func `posted notifications stack in post order`() {
+            let notifier = Notifier()
+
+            notifier.post(
+                .info,
+                message: "First",
+                symbol: "1.circle"
+            )
+            notifier.post(
+                .warning,
+                message: "Second",
+                symbol: "2.circle"
+            )
+            notifier.post(
+                .error,
+                message: "Third",
+                symbol: "3.circle"
+            )
+
+            #expect(notifier.notifications.map(\.message) == ["First", "Second", "Third"])
+        }
+
+    }
+
+    // MARK: Dismissal
+
+    @MainActor
+    @Suite("Dismissal")
+    struct Dismissal {
+
+        @Test func `a notification dismisses itself after the delay`() async throws {
+            let notifier = Notifier(
+                delayDismissal: .seconds(0.2)
+            )
+
+            notifier.post(
+                .info,
+                message: "This is a notification.",
+                symbol: "info.circle"
+            )
+
+            try await Task.sleep(for: .seconds(0.1))
+
+            #expect(notifier.notifications.count == 1)
+
+            try await Task.sleep(for: .seconds(0.2))
+
+            #expect(notifier.notifications.isEmpty)
+        }
+
+        @Test func `notifications dismiss independently`() async throws {
+            let notifier = Notifier(
+                delayDismissal: .seconds(0.3)
+            )
+
+            notifier.post(
+                .info,
+                message: "First",
+                symbol: "1.circle"
+            )
+
+            try await Task.sleep(for: .seconds(0.2))
+
+            notifier.post(
+                .warning,
+                message: "Second",
+                symbol: "2.circle"
+            )
+
+            try await Task.sleep(for: .seconds(0.2))
+
+            #expect(notifier.notifications.map(\.message) == ["Second"])
+
+            try await Task.sleep(for: .seconds(0.2))
+
+            #expect(notifier.notifications.isEmpty)
+        }
+
+    }
+
+}