Swift 如何在每天午夜重置布尔值

你的计时器没问题.

你的代码中有几个问题:

1. 将class Daily个代码移到顶层.这将删除@ObservableObject错误.

2. 将@State var daily更改为@StateObject.这将使@ObservableObject正确更新.

3. 不要将函数getBool()与@State一起使用.直接使用@Published var timedbool，就像daily.timedbool一样.

4. 在Body navig2 = true行中，您返回了一个Bool，您应该在其中返回一个View.你需要在这里放一个视角.

以下是我的改变:

import SwiftUI

class Daily: ObservableObject {
    @Published var timedbool: Bool = false
    private var timer: Timer?
    
    init() {
        scheduleDailyReset()
    }
    private func scheduleDailyReset() {
        let calendar = Calendar.current
        guard let tomorrow = calendar.date(byAdding: .day, value: 1, to: calendar.startOfDay(for: .now)) else {
//        guard let tomorrow = calendar.date(byAdding: .second, value: 5, to: .now) else { // use this instead to test
            print("There's no tomorrow.")
            return
        }
        
        let timeInterval = tomorrow.timeIntervalSinceNow
        timer = Timer.scheduledTimer(timeInterval: timeInterval, target: self, selector: #selector(setBool), userInfo: nil, repeats: false)
        print("timer: \(timer?.fireDate)")
    }
    
    @objc func setBool() {
        timedbool = true
        scheduleDailyReset()
    }
}

struct ContentView: View {
    @StateObject var daily = Daily()
    
    var body: some View {
        VStack {
            Button("Confirm") {
                daily.timedbool = false  // set @Published var
            }
            .disabled(!daily.timedbool) // use @Published var
        }
        .padding()
        .onChange(of: daily.timedbool) { bool in // use @Published var
            print("timed bool set to \(bool)")
        }
    }
}

请注意，带有按钮的视图只是如何在视图中获取和设置timedbool的示例.

还有一个备用的Fire Date定义，因此您不必通宵查看它是否有效.

我更喜欢在这里用guard语句来展开可选的Date，以避免缩进.