アプリへのMusicKitの統合

4:47 - Presents the Apple Music subscription offer

@State var showSubscriptionOffer = false

let options = MusicSubscriptionOffer.Options(
    messageIdentifier: .playMusic
)

@ViewBuilder
var musicSubsriptionButton: some View {
    Button("Subscribe to Apple Music", systemImage: "music.note") {
        showSubscriptionOffer = true
    }
    .musicSubscriptionOffer(isPresented: $showSubscriptionOffer, options: options)
}

5:59 - Adds subscription button to main view

@State var subscription: MusicSubscription?

var body: some View {
  	VStack {
        // ...
        if let subscription, subscription.canBecomeSubscriber {
            musicSubscriptionButton
        }
    }
    .task(id: isAuthorized) {
	      self.subscription = try? await MusicSubscription.current
        for await subscription in MusicSubscription.subscriptionUpdates {
            self.subscription = subscription
        }
    }
}

8:48 - Add .musicPicker() modifier

@State var showMusicPicker = false
@State var selectedSong: Song? = nil

@ViewBuilder
var musicPickerButton: some View {
    Button("Pick some Music", systemImage: "music.note.list") {
        showMusicPicker = true
    }
    .musicPicker(isPresented: $showMusicPicker, selection: $selectedSong)
}

var body: some View {
    VStack {
        if let subscription, subscription.canBecomeSubscriber {
            musicSubscriptionButton
        }
        musicPickerButton
    }
}

14:49 - Artwork

@State var queue = ApplicationMusicPlayer.shared.queue

var body: some View {
    VStack {
        if let artwork = queue.currentEntry?.artwork {
            ArtworkImage(artwork, width: 200, height: 200)
        } else {
            // Placeholder artwork
            RoundedRectangle(cornerRadius: 16)
                .fill(.quaternary)
                .frame(width: 200, height: 200)
        }
    }
}

15:06 - Current entry info

@State var queue = ApplicationMusicPlayer.shared.queue

var body: some View {
    VStack {
        // ...
        if let currentSong = queue.currentEntry {
            Text(currentSong.title)
                .font(.title3.bold())
              
            if let subtitle = currentSong.subtitle {
                Text(subtitle)
                    .font(.subheadline)
                    .foregroundStyle(.secondary)
            }
        }
    }
}

15:14 - Playback controls (play, pause)

let player = ApplicationMusicPlayer.shared
@State var state = ApplicationMusicPlayer.shared.state

var isPlaying: Bool {
    state.playbackStatus == .playing
}

var playPause: some View {
    Button (
        isPlaying ? "Pause": "Play",
        systemImage: isplaying ? "pause.fill" : "play.fill"
    ) {
        if isPlaying {
            player.pause()
        } else {
            Task {
                try await player.play()
            }
        }
    }
}

15:38 - Playback controls (next, previous)

let player = ApplicationMusicPlayer.shared

var controls: some View {
    HStack {
        Button("Back", systemImage: "backward.fill") {
            Task {
                try await player.skipToPreviousEntry()
            }
        }
        // ...
        Button("Next", systemImage: "forward.fill") {
            Task {
                try await player.skipToNextEntry()
            }
        }
    }
}

18:58 - Music catalog resource request

func fetchSongs(songIDs: [MusicItemID]) async throws -> (featured: Song?, other: [Song]) {
    var request = MusicCatalogResourceRequest‹Song>(matching: \.id, memberOf: songIDs)
    request.options = [.findEquivalents]
    
    let response = try await request.response()
    
    let featuredSongID = songIDs[0]
    let featuredSong = response.item(for: featuredSongID)
    
    let others: [Song] = songIDs[1...].compactMap { songID in
        return response.item(for: songID)
    }
    
    return (featuredSong, others)
}