How to pass different objects and change view depending on what is passed?

September 5, 2022

I got two different Objects Song and Album. I got an AlbumView with a @State var album: Album and I want to reuse that View but pass a Song instead. Is it possible to pass either Album or Song? Otherwise it would also be helpful if I could set Album to nil and then just check in the View whether it has a value.

This is what Album looks like:

struct Album: Identifiable {
    let id = UUID()
    let name: String
    let artist: String
    let songs: [AlbumSong]
    let releaseDate: Date
    let price: Int
    let albumImageUrl: String
    var unlocked: Bool
}

This is what Song looks like:

struct Song: Identifiable, Codable {
    let id = UUID()
    let title: String
    let duration: TimeInterval
    var image: String
    let artist: String
    let track: String
    let price: Int
}

This is my AlbumView:

struct AlbumView: View {
@State var album: Album

var body: some View {
   Text("\(album.name)").font(.system(size: 18))
   }
}

This would be my idea to solve it with passing one object as nil:

struct AlbumView: View {
    @State var album: Album?
    @State var song: Song
    
    var body: some View {
        if album != nil {
            Text("\(album!.name)")
        } else {
            Text("\(song.name)")
        }
    }
}

>Solution :

There are multiple ways to do this:

Enum

enum SomeType {
    case song(Song)
    case album(Album)
}

Then in your View you pass a type to AlbumView & display it like so:

struct AlbumView: View {
    @State var type: SomeType
    var body: some View {
       switch type {
           case .album(let album):
               Text("\(album.name)")
           case .song(let song):
               Text("\(song.name)")
       }
   }
}

You pass the type like so:

AlbumView(type: .album(someAlbum))//for albums
AlbumView(type: .song(someSong))//for songs

Protocol

If you’re using shared property names:

protocol SomeMedia {
    var name: String {get set}
    //any other shared property
}

struct AlbumView: View {
    @State var media: SomeMedia
    var body: some View {
        Text("\(media.name)")
    }
}

Make Album & Song conform to SomeMedia, then you can pass a song or an album as you require!