如何在 Swift3 中执行 timeIntervalSinceNow？

Question

我正在发出通知并观看有关它的教程，当我输入时：

notification.fireDate = NSDate(timeIntervalSinceNow: 0)

它说

参数标签“(timeIntervalSinceNow:)”不匹配任何可用的 重载

我该如何解决这个问题？这是我的代码：

import UIKit
import UserNotifications

class ViewController: UIViewController {
    var timer = Timer()
    var time = 10
    override func viewDidLoad() {
        super.viewDidLoad()
        timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: Selector(("Notification")), userInfo: nil, repeats: true)
        // Do any additional setup after loading the view, typically from a nib.
    }
    func notification() {
        time -= 1
        if time <= 0 {
            let notification = UILocalNotification()
            notification.alertAction = "Call"
            notification.alertBody = "You have a call right now"
            notification.fireDate = NSDate(timeIntervalSinceNow: 0)
            UIApplication.shared.scheduleLocalNotification(notification)
            timer.invalidate()
        }
    }
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    @IBAction func pushNotification(_ sender: AnyObject) {
        let AlertView = UIAlertController(title: "Time for your call!", message: "Press go to continue", preferredStyle:  .alert)
        AlertView.addAction(UIAlertAction(title: "Go", style: .default, handler: nil))
        self.present(AlertView, animated: true, completion: nil)
    }
}

Answer 1

如果您希望开火日期是现在，那就是：

notification.fireDate = Date()

---

正如 Leo 在其他地方所指出的，选择器不正确。应该是：

weak var timer: Timer?
var time = 10

override func viewDidLoad() {
    super.viewDidLoad()

    timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(handleTimer(_:)), userInfo: nil, repeats: true)
}

func handleTimer(_ timer: Timer) {
    time -= 1

    if time <= 0 {
        let notification = UILocalNotification()

        notification.alertAction = "Call"
        notification.alertBody = "You have a call right now"
        notification.fireDate = Date()

        UIApplication.shared.scheduleLocalNotification(notification)

        timer.invalidate()
    }
}

然后你问：

这绝对有效，但现在我离开应用程序时没有收到通知

离开应用时不会收到通知，因为在应用不运行时Timer 不会继续触发。最好完全取消计时器并立即将本地通知安排到所需的时间。例如，安排本地通知在 10 秒内触发：

override func viewDidLoad() {
    super.viewDidLoad()

    scheduleLocalNotification(delay: 10)
}

func scheduleLocalNotification(delay: TimeInterval) {
    let notification = UILocalNotification()

    notification.alertAction = "Call"
    notification.alertBody = "You have a call right now"
    notification.fireDate = Date().addingTimeInterval(delay)

    UIApplication.shared.scheduleLocalNotification(notification)
}

Answer 2

斯威夫特 3

let minute:TimeInterval = 11.0 * 60.0;
Date(timeIntervalSinceNow: minute);

到现在 +11 分钟。