SwiftUI Lifecycle Listeners

gistfile1.txt

@State private var videoCompleteTask: Task<Void, Error>?
@State private var showContinueButton: Bool = false
@State private var videoDurationRemaining: Double = 12

var body: some View {
  // ...
  .onAppear {
      resetVideoCompleteTask()
  }
  .onDisappear {
      videoCompleteTask?.cancel()
  }
  .onReceive(NotificationCenter.default.publisher(for: UIApplication.didEnterBackgroundNotification)) { _ in
      videoCompleteTask?.cancel()
  }
  .onReceive(NotificationCenter.default.publisher(for: UIApplication.willEnterForegroundNotification)) { _ in
      resetVideoCompleteTask()
  }

private func resetVideoCompleteTask() {
    videoCompleteTask?.cancel()
    videoCompleteTask = Task {
        while !Task.isCancelled,
              videoDurationRemaining > 0
        {
            try? await Task.sleep(for: .seconds(0.1))
            videoDurationRemaining -= 0.1
            if videoDurationRemaining <= 0 {
                showContinueButton = true
            }
        }
    }
}