swift - AnimateKeyframes 同时运行所有关键帧 (Swift)

Question

我正在尝试对标签进行动画处理，以在不同关键帧处使用不同的单词更改其文本，但它只是跳到最后一个关键帧(“晚安”)，而不显示之前的关键帧。它确实打印了它们，所以我猜持续时间或开始时间有问题，但我不知道它可能是什么..

func changeText() {

    let options = UIView.KeyframeAnimationOptions.calculationModeLinear

    UIView.animateKeyframes(withDuration: 10, delay: 0, options: options, animations: {

        UIView.addKeyframe(withRelativeStartTime: 0.0, relativeDuration: 0.25, animations: {
            self.label.text = "Good Morning"
            print("Morning")
        })

        UIView.addKeyframe(withRelativeStartTime: 0.25, relativeDuration: 0.25, animations: {
            self.label.text = "Good Afternoon"
            print("Afternoon")
        })

        UIView.addKeyframe(withRelativeStartTime: 0.5, relativeDuration: 0.25, animations: {
            self.label.text = "Good Evening"
            print("Evening")
        })
        UIView.addKeyframe(withRelativeStartTime: 0.75, relativeDuration: 0.25, animations: {
            self.label.text = "Good Night"
            print("Night")
        })

    }, completion: nil)
}

@IBAction func didPressBtn(_ sender: Any) {
    changeText()
}

Answer 1

这应该能达到你的目的吗？

 func changeText() {

 label.text = "Good Morning"
 print("Morning")
 sleep(2.5)

 label.text = "Good Afternoon"
 print("Morning")
 sleep(2.5)

 label.text = "Good Evening"
 print("Morning")
 sleep(2.5)

 label.text = "Good Night"
 print("Morning")
 sleep(2.5)

 }