Implemented in-app download notifications on the ContentView view in the Sample app target.

Apps/Attendi/Catalogs/Localizable.xcstrings

@@ -11,6 +11,42 @@
         }
       }
     },
+    "view.recording.notification.download.cancelled" : {
+      "comment" : "The message of the notification for a cancelled speech model download.",
+      "extractionState" : "manual",
+      "localizations" : {
+        "en" : {
+          "stringUnit" : {
+            "state" : "translated",
+            "value" : "The speech model download for %@ was cancelled."
+          }
+        }
+      }
+    },
+    "view.recording.notification.download.failed" : {
+      "comment" : "The message of the notification for a failed speech model download.",
+      "extractionState" : "manual",
+      "localizations" : {
+        "en" : {
+          "stringUnit" : {
+            "state" : "translated",
+            "value" : "The speech model for %@ could not be downloaded."
+          }
+        }
+      }
+    },
+    "view.recording.notification.download.started" : {
+      "comment" : "The message of the notification for a started speech model download. ",
+      "extractionState" : "manual",
+      "localizations" : {
+        "en" : {
+          "stringUnit" : {
+            "state" : "translated",
+            "value" : "Downloading the speech model for %@…"
+          }
+        }
+      }
+    },
     "view.recording.picker.locale.title" : {
       "localizations" : {
         "en" : {

Apps/Attendi/Views/ContentView.swift

@@ -5,21 +5,27 @@ import SwiftUI
 ///
 /// The view hosts the `RecordingView` feature from the `Recording` target of the `Features` package, which drives the whole recording flow,
 /// inside a navigation stack, and presents the transcribed text of every processed recording in a modal sheet of its own navigation stack.
+/// A toolbar menu picks the locale of the spoken language to transcribe, and every pick kicks off the preinstallation of the locale's speech
+/// model assets, whose download events surface as transient in-app notifications overlaying the feature just below the navigation bar.
 ///
-/// The services attached to the feature and the transcription shown in the sheet live in the view's ``Model``; the view itself only renders it and
+/// The services attached to the feature, the transcription shown in the sheet, and the posted notifications live in the view's ``Model``;
-/// forwards the feature's output and the sheet's dismissal. The navigation titles of the stacks are localized through the app's string catalog.
+/// the view itself only renders it and forwards the feature's output, the picker's changes, and the sheet's dismissal. All user-facing text
+/// is localized through the app's string catalog.
 struct ContentView: View {
 
     // MARK: Properties
 
-    /// The model that owns the attached services and the transcription presented in the modal sheet.
+    /// The model that owns the attached services, the transcription presented in the modal sheet, and the posted in-app notifications.
     @State private var model = Model()
 
     // MARK: Body
 
-    /// The content of the view: a navigation stack with the recording feature's view, attached to the model's services, with a toolbar picker
+    /// The content of the view: a navigation stack with the recording feature's view, attached to the model's services and expanded to fill
-    /// for the locale of the spoken language to transcribe, and a modal sheet presenting the transcribed text of every processed recording —
+    /// the available space, with a toolbar picker for the locale of the spoken language to transcribe, and a modal sheet presenting the
-    /// or a content unavailable message when the transcription is empty — closable through its toolbar button or a swipe.
+    /// transcribed text of every processed recording — or a content unavailable message when the transcription is empty — closable
+    /// through its toolbar button or a swipe. The model's in-app notifications overlay the feature, stacking downward just below the
+    /// navigation bar; each one slides in from the leading edge when posted and out again when its scheduled dismissal arrives, without
+    /// displacing the recording controls underneath.
     var body: some View {
         NavigationStack {
             RecordingView(
@@ -29,81 +35,192 @@ struct ContentView: View {
             ) { transcription in
                 model.received(transcription)
             }
+            .frame(
+                maxWidth: .infinity,
+                maxHeight: .infinity
+            )
             .navigationTitle("view.recording.navigation.title")
             #if !os(macOS)
             .navigationBarTitleDisplayMode(.inline)
             #endif
             .toolbar {
                 ToolbarItem(placement: .primaryAction) {
-                    Menu {
+                    menuLocale
-                        Picker(
-                            "view.recording.picker.locale.title",
-                            selection: $model.locale
-                        ) {
-                            ForEach(
-                                model.locales,
-                                id: \.self
-                            ) {
-                                Text(model.name(for: $0))
-                                    .tag($0)
-                            }
-                        }
-                        .pickerStyle(.inline)
-                    } label: {
-                        Label(
-                            "view.recording.picker.locale.title",
-                            systemImage: "globe"
-                        )
-                    }
-                    .disabled(model.locales.isEmpty)
                 }
             }
+            .overlay(
+                alignment: .topLeading
+            ) {
+                stackNotifications
+            }
             .task {
                 await model.load()
             }
-            .task(id: model.locale) {
+            .onChange(
-                await model.preinstallAssets()
+                of: model.locale,
+                initial: false
+            ) {
+                model.preinstall()
             }
         }
         .sheet(item: $model.transcription) { transcription in
-            NavigationStack {
+            sheetTranscription(for: transcription)
-                Group {
-                    if transcription.isEmpty {
-                        ContentUnavailableView(
-                            "view.transcription.unavailable.title",
-                            systemImage: "text.page.slash",
-                            description: Text("view.transcription.unavailable.description")
-                        )
-                    } else {
-                        ScrollView {
-                            Text(transcription.text)
-                                .font(.body)
-                                .fontWeight(.regular)
-                                .foregroundStyle(.primary)
-                                .frame(
-                                    maxWidth: .infinity,
-                                    alignment: .leading
-                                )
-                                .padding()
-                        }
-                    }
-                }
-                .navigationTitle("view.transcription.navigation.title")
-                #if !os(macOS)
-                .navigationBarTitleDisplayMode(.inline)
-                #endif
-                .toolbar {
-                    Button(role: .close) {
-                        model.dismissed()
-                    }
-                }
-            }
-            .presentationDetents([.medium, .large])
         }
     }
 
 }
 
+// MARK: - Subviews
+
+private extension ContentView {
+
+    // MARK: Computed
+
+    /// The toolbar menu that picks the locale of the spoken language to transcribe from the supported locales, disabled until
+    /// they are loaded.
+    var menuLocale: some View {
+        Menu {
+            Picker(
+                "view.recording.picker.locale.title",
+                selection: $model.locale
+            ) {
+                ForEach(
+                    model.locales,
+                    id: \.self
+                ) {
+                    Text(model.name(for: $0))
+                        .tag($0)
+                }
+            }
+            .pickerStyle(.inline)
+        } label: {
+            Label(
+                "view.recording.picker.locale.title",
+                systemImage: "globe"
+            )
+        }
+        .disabled(model.locales.isEmpty)
+    }
+
+    /// The stack of the model's in-app notifications, each one sliding in from the leading edge when posted and out again when
+    /// its scheduled dismissal arrives.
+    var stackNotifications: some View {
+        VStack(
+            alignment: .leading,
+            spacing: Constant.Spacing.stack
+        ) {
+            ForEach(
+                model.notifications
+            ) { notification in
+                Label {
+                    Text(notification.textMessage)
+                } icon: {
+                    Image(systemName: notification.imageSymbol)
+                }
+                .labelStyle(.notification(
+                    event: notification.event
+                ))
+                .transition(.move(
+                    edge: .leading
+                ).combined(
+                    with: .opacity
+                ))
+            }
+        }
+        .padding(.horizontal)
+        .animation(
+            .spring,
+            value: model.notifications
+        )
+    }
+
+    // MARK: Methods
+
+    /// Returns the content of the modal sheet presenting the given transcription — or a content unavailable message when it is
+    /// empty — inside a navigation stack of its own, closable through its toolbar button or a swipe.
+    ///
+    /// - Parameter transcription: The transcription to present.
+    /// - Returns: The content of the modal sheet.
+    func sheetTranscription(
+        for transcription: Transcription
+    ) -> some View {
+        NavigationStack {
+            Group {
+                if transcription.isEmpty {
+                    ContentUnavailableView(
+                        "view.transcription.unavailable.title",
+                        systemImage: "text.page.slash",
+                        description: Text("view.transcription.unavailable.description")
+                    )
+                } else {
+                    ScrollView {
+                        Text(transcription.text)
+                            .font(.body)
+                            .fontWeight(.regular)
+                            .foregroundStyle(.primary)
+                            .frame(
+                                maxWidth: .infinity,
+                                alignment: .leading
+                            )
+                            .padding()
+                    }
+                }
+            }
+            .navigationTitle("view.transcription.navigation.title")
+            #if !os(macOS)
+            .navigationBarTitleDisplayMode(.inline)
+            #endif
+            .toolbar {
+                Button(role: .close) {
+                    model.dismissed()
+                }
+            }
+        }
+        .presentationDetents([.medium, .large])
+    }
+
+}
+
+// MARK: - AppNotification+Extensions
+
+private extension AppNotification {
+    
+    // MARK: Properties
+    
+    /// 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"
+        }
+    }
+    
+    // MARK: Methods
+    
+    /// 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)
+        }
+    }
+    
+}
+
+
+// MARK: - Constants
+
+/// The constant values used across the view.
+private enum Constant {
+    /// The spacing constants.
+    enum Spacing {
+        /// The spacing between the elements of a stack.
+        static let stack: CGFloat = 8
+    }
+}
+
 // MARK: - Previews
 
 #Preview(