Check out example codes for "Blinking effect on UILabel". It will help you in understanding the concepts better.
Code Example 1
extension UILabel {
func startBlink() {
UIView.animate(withDuration: 0.8,
delay:0.0,
options:[.allowUserInteraction, .curveEaseInOut, .autoreverse, .repeat],
animations: { self.alpha = 0 },
completion: nil)
}
func stopBlink() {
layer.removeAllAnimations()
alpha = 1
}
}
//Useage e.g.
loginButton.blink(duration: 1, delay: 0.1, alpha: 0.0100000003)
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