嘿，我想在设备的时钟敲到下午 6 点时将我的应用程序模式从白天更改为夜晚，并在时钟敲到早上 6 点时再次更改它。现在我每秒使用计时器来检查时间并触发我的函数。但我觉得这不是最好的方法。
您好，是的，您的方法不是最好的方法，因为这会消耗用户的设备的电池寿命。我在项目中应用了一个技巧。你可以做一件事，当你的应用程序启动时，检查"特定时间"是否已到达。并且您还需要在设备"时区"或"时钟时间"更改时进行检查。
func checkTimeToFireMethod(){
let calendar = NSCalendar(calendarIdentifier: NSCalendar.Identifier.gregorian)!
let date = Date()
calendar.locale = Locale(identifier: "en_US_POSIX")
let hour = calendar.component(.hour, from: date)
let minutes = calendar.component(.minute, from: date)
let seconds = calendar.component(.second, from: date)
let timeNowInSeconds = seconds + minutes*60 + hour*3600
var timeLeft = 0
// 6 am (06:00:00) changes to seconds (6*3600) and current time in seconds. here we are checking if the current time is less than 6:00:00 am
if timeNowInSeconds < 6*3600{
timeLeft = 6*3600 - timeNowInSeconds
}
// 6 pm (18:00:00) changes to seconds (18*3600) and current time in seconds. here we are checking if the current time is between 6:00:00 am and 6:00:00 pm.
if timeNowInSeconds < 18*3600 && timeNowInSeconds >= 6*3600{
timeLeft = 18*3600 - timeNowInSeconds
}
// 6 pm (18:00:00) changes to seconds (18*3600) and current time in seconds. here we are checking if the current time is greater than 6:00:00 am and 6:00:00 pm.
else if timeNowInSeconds >= 18*3600{
timeLeft = 24*3600 - timeNowInSeconds
}
// to avoid any descripancy
// check 30 seconds prior to actual time
self.perform(#selector(self.myFuncation), with: nil, afterDelay: TimeInterval(timeLeft - 30))
// check on time
self.perform(#selector(self.myFuncation), with: nil, afterDelay: TimeInterval(timeLeft))
// check 30 seconds after actual time
self.perform(#selector(self.myFuncation), with: nil, afterDelay: TimeInterval(timeLeft + 30))
}
然后调用您的函数来执行您的任务
func myFuncation(){
}
还添加以下通知：-
NotificationCenter.default.addObserver(self, selector: #selector(self.checkTimeToFireMethod), name: NSNotification.Name.NSSystemClockDidChange, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(self.checkTimeToFireMethod), name: NSNotification.Name.NSSystemTimeZoneDidChange, object: nil)