How to use KVO for UserDefaults in Swift?

Question

I\'m rewriting parts of an app, and found this code:

fileprivate let defaults = UserDefaults.standard

func storeValue(_ value: AnyObject, forKey key:String) {
          


        

Answer 1

For anyone who will be looking for the answer in the future, didChangeNotification will be posted only if changes are made on the same process, if you would like to receive all updates regardless of the process use KVO.

Apple doc

This notification isn't posted when changes are made outside the current process, or when ubiquitous defaults change. You can use key-value observing to register observers for specific keys of interest in order to be notified of all updates, regardless of whether changes are made within or outside the current process.

Here is a link to demo Xcode project which shows how to setup block based KVO on UserDefaults.