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[Solved] How can I use UserDefaults here, kindly guide

Forums > SwiftUI

I was using this code prior to using UserDefaults , all worked well -

class Songs: ObservableObject {
    @Published var songs: [Song]

    init(){
           self.songs =
            [
                Song(name: "demo", album: "demo", genre: "demo", artist: "demo"),                
                 Song(name: "demo", album: "demo", genre: "demo", artist: "demo"),
                Song(name: "demo", album: "demo", genre: "demo", artist: "demo"),
                 Song(name: "demo", album: "demo", genre: "demo", artist: "demo"),
                 Song(name: "demo", album: "demo", genre: "demo", artist: "demo"),
            ]

       }

}

Now i wanted to save the data permanently , but as the data was trivial i did not use core data , insead went for UserDefaults and used the code below, and now the code does not show the data in list etc, how can i make this work with UserDefaults, thanks

class Songs: ObservableObject {

               var songsData =
    [
                 Song(name: "demo", album: "demo", genre: "demo", artist: "demo"),                
                 Song(name: "demo", album: "demo", genre: "demo", artist: "demo"),
                Song(name: "demo", album: "demo", genre: "demo", artist: "demo"),
                 Song(name: "demo", album: "demo", genre: "demo", artist: "demo"),
                 Song(name: "demo", album: "demo", genre: "demo", artist: "demo"),
                ]

    @Published var songs: [Song] {
        didSet {
            UserDefaults.standard.set(songsData, forKey: "demosongs")
        }

    }

    init(){

        self.songs = UserDefaults.standard.object(forKey: "demosongs") as? [Song] ?? [Song.default]
       }

}

   

@Obelix - hii, yeah a great lesson, my problem seems to stem from trying to save array and not knowing where is the best place to feed the value to UserDefaults, i just tried at onappear etc , but they seem to throw runtime errors, is the below code write way , as the UserDefaults is not getting the values , thanks

@Published var songs: [Song] {
        didSet {
            UserDefaults.standard.set(songsData, forKey: "demosongs")
        }

    }

   

had to do this -

@Published var songs = [Song]() {
        didSet {
            if let encoded = try? JSONEncoder().encode(songs) {
                UserDefaults.standard.set(encoded, forKey: "demosongs")
            }
        }
    }

and then in init

 if let savedItems = UserDefaults.standard.data(forKey: "demosongs") {
               if let decodedItems = try? JSONDecoder().decode([Song].self, from: savedItems) {
                   songs = decodedItems
                   return
               }

           }
           songs = songsData

   

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