倒数计时器 SwiftUI

Question

如何每天在特定时间制作倒数计时器。 当我再次打开应用程序时，计时器被重置并且倒计时再次开始，我试图弄清楚如何让计时器在它的时间过去后再次启动..

例如，让这个计时器在每天下午 6 点重新开始

struct TimerView: View {
    //MARK: - PROPERTIES
    @State var timeRemaining = 24*60*60
    
    let timer = Timer.publish(every: 1, on: .main, in: .common).autoconnect()

    //MARK: - BODY
    var body: some View {
        
        Text("\(timeString(time: timeRemaining))")
            .font(.system(size: 60))
            .frame(height: 80.0)
            .frame(minWidth: 0, maxWidth: .infinity)
            .foregroundColor(.white)
            .background(Color.black)
            .onReceive(timer){ _ in
                if self.timeRemaining > 0 {
                    self.timeRemaining -= 1
                }else{
                    self.timer.upstream.connect().cancel()
                }
            }
    }
    
    //Convert the time into 24hr (24:00:00) format
    func timeString(time: Int) -> String {
        let hours   = Int(time) / 3600
        let minutes = Int(time) / 60 % 60
        let seconds = Int(time) % 60
        return String(format:"%02i:%02i:%02i", hours, minutes, seconds)
    }
}

Answer 1

计时器重置，倒计时再次开始

您可以尝试使用 UserDefaults 将变量存储在设备的 memory 中。

这是文档： https://developer.apple.com/documentation/foundation/userdefaults

Answer 2

看看TimelineView和AppStorage例如

@AppStorage("StartDate") var startDate: Date
...
TimelineView(.periodic(from: startDate, by: 1)) { context in
    AnalogTimerView(date: context.date)
}