I'm currently prototyping a timer app in Swift Playgrounds. The code for the top-level view and the child view is the following: import SwiftUI import Foundation import PlaygroundSupport struct MultiTimerView: View {     @State private var timerList = [TimerManager]()     var body: some View {         VStack(spacing: 20){             ForEach(timerList.indices, id: \.self) { id in                 SingleTimerView(timerManager: self.$timerList[id])             }             Spacer()             Button(action:addTimer){                 Image(systemName:"plus")             }         }     }          func addTimer(){         timerList.append(TimerManager())     } } struct SingleTimerView: View {     @Binding var timerManager : TimerManager     var body: some View {         HStack(spacing: 20){             Spacer()             Stepper("\(timerManager.secondsLeft)", value: $timerManager.secondsLeft, in: 0...1000)             Spacer()             Button(action:self.timerManager.toggleTimer){                 Image( systemName: self.timerManager.timerRunning ? "pause.fill" : "play.fill")             }             Spacer()         }      } } PlaygroundPage.current.setLiveView(MultiTimerView().padding(50)) The code for the TimerManager class is the following: import SwiftUI import Foundation import PlaygroundSupport public class TimerManager: ObservableObject,Identifiable{     @Published public var timerRunning = false     @Published public var secondsLeft = 0     var timer = Timer()     public var id = UUID()     public init() {}     public func toggleTimer(){         if timerRunning == false {             timer = Timer.scheduledTimer(withTimeInterval: 1.0, repeats: true , block: { timer in                 if self.secondsLeft == 0 {                     self.timerRunning = false                     self.secondsLeft = 0                     timer.invalidate()                 } else {                     self.secondsLeft-=1                 }             })         } else {             timer.invalidate()         }         timerRunning.toggle()     } } The bug happens doing the following: create a timer with the + button load the timer a given amount of seconds with its stepper on the right side press its play button wait a couple of seconds and then add another timer You'll see that the amount of remaining seconds for a running timer is not updated live, but only when refreshing the view by adding another timer to the list. How can I fix this bug?