Here is possible solution
import Combine
// define key for observing
extension UserDefaults {
@objc dynamic var status: String {
get { string(forKey: "status") ?? "OFFLINE" }
set { setValue(newValue, forKey: "status") }
}
}
class Station: ObservableObject {
@Published var status: String = UserDefaults.standard.status {
didSet {
UserDefaults.standard.status = status
}
}
private var cancelable: AnyCancellable?
init() {
cancelable = UserDefaults.standard.publisher(for: \.status)
.sink(receiveValue: { [weak self] newValue in
guard let self = self else { return }
if newValue != self.status { // avoid cycling !!
self.status = newValue
}
})
}
}
Note: SwiftUI 2.0 allows you to use/observe UserDefaults
in view directly via AppStorage
, so if you need that status only in view, you can just use
struct SomeView: View {
@AppStorage("status") var status: String = "OFFLINE"
...