[User Defaults] Couldn't write values for keys

Hello everyone,

I have problems using SharedUserDefaults with a keyboard-extension.

I could not reproduce the error-message in the simulator, it only appears on real devices.

I created

Code Block language
struct SharedUserDefaults {
static let suiteName = "group.***.MyGroup"
  struct Keys {
    static let addon = "addon"
    static let lastcomment = "lastcomment"
   }
}

Target Membership both my main-app and keyboard-extension.


In the app I load

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let sharedUserDefaults = UserDefaults(suiteName: SharedUserDefaults.suiteName)

and save a textfield to it.

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if let var_textfield = textfield_addon.text {
      sharedUserDefaults?.set(var_textfield, forKey: SharedUserDefaults.Keys.addon)
    }

I can also load this here, everything works.

Inside my extension I load it with

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guard let var_addon = sharedUserDefaults?.string(forKey: SharedUserDefaults.Keys.addon)
        else {return ""}
      return var_addon

This also works in the simulator, but not on my real device.

It always takes the first value I have saved inside the app the first time:

app > save "1" > extension load > "1"
app > save "2" > extension load > "1"

The only hint I have is when saving a value inside the extension I get a message

[User Defaults] Couldn't write values for keys (lastcomment)in CFPrefsPlistSource<0x2817f5b00> (Domain: group.***.MyGroup, User: kCFPreferencesCurrentUser, ByHost: No, Container: (null), Contents Need Refresh: No): setting preferences outside an application's container requires user-preference-write or file-write-data sandbox access

Unfortunately I was not able to solve it with this message, as also the online-tutorials do it like my current code.



I am running iOS 14.2.1, I am quite sure that this was working on iOS 13, but unfortunately I have no second device with iOS 13 to test now.