如何格式化 elapsedTime 从 00:00:00 开始而不是 Swift 中的默认 07:00:00

How to format elapsedTime start at 00:00:00 instead of the default 07:00:00 in Swift

我找不到使用 QuartzCore 让秒表显示从 00:00:00 开始的方法。它总是从 07:00:00.

开始

有没有办法将开始时间格式化为 00:00:00?代码如下。

谢谢!!

Class:

import Foundation
import QuartzCore

class StopWatch: NSObject{

private var displayLink: CADisplayLink!
private let formatter = DateFormatter()

var callback: (() -> Void)?
var elapsedTime: CFTimeInterval!

override init() {
    super.init()
    self.displayLink = CADisplayLink(target: self, selector: #selector(tick(sender:)))
    displayLink.isPaused = true
    displayLink.add(to: RunLoop.main, forMode: RunLoopMode.commonModes)
    self.elapsedTime = 0.0
    formatter.dateFormat = "HH:mm:ss"
}
convenience init(withCallback callback: @escaping () -> Void) {
    self.init()
    self.callback = callback
}
deinit {
    displayLink.invalidate()
}

func tick(sender: CADisplayLink) {
    elapsedTime = elapsedTime + displayLink.duration
    callback?()
}


func elapsedTimeAsString() -> String {
    return formatter.string(from: Date(timeIntervalSinceReferenceDate:elapsedTime))
}

}

已更正,如下评论所述: 正如上面提到的评论者,这是一个时区问题,因为我位于 GMT +7。我添加了以下代码来解决问题:

formatter.timeZone = 时区(缩写:"GMT")!