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UserDefaults in a CoreData class, refresh issue.

Forums > SwiftUI

Hi,

I have a CoreData class where I load a static var from UserDefaults. When the value of it changes, the display doesn't get refreshed except if I kill the app and reload. I understand why but I don't know how to solve this issue. Any idea?

Thanks Alessandro

1      

hi Alessandro,

  • don't know who @Amina3432 is or why he or his bot is spamming all these posts with suspicious links ...

if you have a display (View) that wants to be sensitive to changes in your user defaults (an entity in Core Data), just be sure you have a @FetchRequest tied to that entity, something like

@FetchRequest(entity: YourUserDefaultEntity.entity(), sortDescriptors: []) 
private var userDefaults: FetchedResults<YourUserDefaultEntity>

then you retrieve the values of the defaults from it (i am guessing there's only one such object)

let userFavoriteBookTitle = userDefaults[0].userFavoriteBookTitle ?? "Hacking With Swift"

any change to the user defaults entity such as

userDefaults[0].userFavoriteBookTitle = "Beyond Code" 

should trigger an update of the display.

hope that helps,

DMG

1      

Thanks DMG,

I retrieved the UserDefaults data directly in the class method and it works as expected now. I wanted to do it at the class level directly because it's a value shared by all the objects but I could not find any better solution. When I mentioned UserDefaults, I meant this one: https://developer.apple.com/documentation/foundation/userdefaults, not a CoreData class named userDefaults :-)

1      

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