UserDefaults observer stopped working after not hardtyping the parameter

Question

My UserDefault observer used to work fine until I replaced my forKeyPath parameter to a string Struct instead of hardtyping it.

How it used to be when it was working:

UserDefaults.standard.addObserver(self, forKeyPath: "packagename.fontSize", options: .new, context: nil)

How it is now (not working anymore)

UserDefaults.standard.addObserver(self, forKeyPath: UserSavedSettings.FontSize, options: .new, context: nil)

After the parameter change the function:

observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?)

is not called anymore...

Here is my UserSavedSettings.FontSize declaration

struct UserSavedSettings {
    static let FontSize = "packagename.fontSize"
    static let FontType = "packagename.fontType"
    static let Theme = "packagename.theme"
}

Any ideas how can I fix this? Thank you in advance!

Answer 1

Well it seems that when I remove the dots on my UserSavedSettings strings it works fine.

struct UserSavedSettings {
    static let FontSize = "packagename_fontSize" // replaced . with _
    static let FontType = "packagename_fontType"
    static let Theme = "packagename_theme"
}

Something must be going wrong with UserDefaults when the string contains dots.