SwiftUI Picker onChange or equivalent?

Deployment target of iOS 14 or newer

Apple has provided a built in onChange extension to View, which can be used like this:

struct MyPicker: View {
    @State private var favoriteColor = 0

    var body: some View {
        Picker(selection: $favoriteColor, label: Text("Color")) {
            Text("Red").tag(0)
            Text("Green").tag(1)
        }
        .onChange(of: favoriteColor) { tag in print("Color tag: \(tag)") }
    }
}

---

Deployment target of iOS 13 or older

struct MyPicker: View {
    @State private var favoriteColor = 0

    var body: some View {
        Picker(selection: $favoriteColor.onChange(colorChange), label: Text("Color")) {
            Text("Red").tag(0)
            Text("Green").tag(1)
        }
    }

    func colorChange(_ tag: Int) {
        print("Color tag: \(tag)")
    }
}

Using this helper

extension Binding {
    func onChange(_ handler: @escaping (Value) -> Void) -> Binding<Value> {
        return Binding(
            get: { self.wrappedValue },
            set: { selection in
                self.wrappedValue = selection
                handler(selection)
        })
    }
}