How to make a button flash or blink?
This should work in Swift 4
extension UIView{
func blink() {
self.alpha = 0.2
UIView.animate(withDuration: 1, delay: 0.0, options: [.curveLinear, .repeat, .autoreverse], animations: {self.alpha = 1.0}, completion: nil)
}
}
This will start and stop a flashing button onClick
, if you only want to flash the button immediately just use the first statement.
var flashing = false
@IBAction func btnFlash_Clicked(sender: AnyObject) {
if !flashing{
self.buttonScan.alpha = 1.0
UIView.animateWithDuration(0.5, delay: 0.0, options: [.CurveEaseInOut, .Repeat, .Autoreverse, .AllowUserInteraction], animations: {() -> Void in
self.buttonScan.alpha = 0.0
}, completion: {(finished: Bool) -> Void in
})
flashing = true
}
else{
UIView.animateWithDuration(0.1, delay: 0.0, options: [.CurveEaseInOut, .BeginFromCurrentState], animations: {() -> Void in
self.buttonScan.alpha = 1.0
}, completion: {(finished: Bool) -> Void in
})
}
}
Swift 5.x version
An updated version with extension
.
extension UIView {
func blink(duration: TimeInterval = 0.5, delay: TimeInterval = 0.0, alpha: CGFloat = 0.0) {
UIView.animate(withDuration: duration, delay: delay, options: [.curveEaseInOut, .repeat, .autoreverse], animations: {
self.alpha = alpha
})
}
}
To call the function:
button.blink() // without parameters
button.blink(duration: 1, delay: 0.1, alpha: 0.2) // with parameters
I hope that will solve your problem.
buttonScan.alpha = 1.0
UIView.animate(withDuration: 1.0, delay: 1.0, options: UIView.AnimationOptions.curveEaseOut, animations: {
buttonScan.alpha = 0.0
}, completion: nil)