Thursday, July 20, 2017

Swift 4: Key-Value Observation

One of the most exciting additions to the Foundation library in iOS 11 that somehow flew under my radar was the new Swift syntax for key value observation. It’s long been known that the KVO API was one of the more obfuscated and confusing in Cocoa, which makes this change so exciting. Not only is it type safe, but also terse as hell[…]

[…]
let observation = foo.observe(\.string) { (foo, change) in
    print("new foo.string: \(foo.string)")
}

Cocoa iOS iOS 11 Key-Value Observing (KVO) Mac macOS 10.13 High Sierra Programming Swift Programming Language