delete subview that use with imageView - ios

Question

I have a map picture in my ImageView and I want a red dot for user current location so I use this 3 lines of code for creating red dot above my ImageView
let overlay: UIView = UIView(frame: CGRect(x: xcorIn * 0.822, y: ycorIn * 1.03, width: 5, height: 5))
overlay.backgroundColor = UIColor(red: 255/255, green: 0/255, blue: 0/255, alpha: 1)
imageView.addSubview(overlay)
all I want is after of 2 seconds of red dot appear it must disappear
so I try this
DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(1), execute: {
self.imageView.delete(overlay)
})
delay function seem work but
self.imageView.delete(overlay)
return me this error
Terminating app due to uncaught exception
'NSInvalidArgumentException', reason: '-[UIImageView delete:]:
unrecognized selector sent to instance 0x7f8bef712df0'

Answer 1

You need to remove overlay from the superView. You could either do this:
DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(1), execute: {
overlay.removeFromSuperview()
})
Or if you don´t have overlay globally, you could do this. Add a tag to your overlay and then do this:
let overlay: UIView = UIView(frame: CGRect(x: 100, y: 100, width: 5, height: 5))
overlay.tag = 0
overlay.backgroundColor = UIColor(red: 255/255, green: 0/255, blue: 0/255, alpha: 1)
imageView.addSubview(overlay)
DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(1), execute: {
for subView in self.imageView.subviews {
if subView.tag == 0 {
subView.removeFromSuperview()
}
}
})

Answer 2

You can remove the dot by using its reference and "removeFromSuperview()" method
let overlay: UIView = UIView(frame: CGRect(x: xcorIn * 0.822, y: ycorIn * 1.03, width: 5, height: 5))
overlay.backgroundColor = UIColor(red: 255/255, green: 0/255, blue: 0/255, alpha: 1)
imageView.addSubview(overlay)
DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(1), execute: {
overlay.removeFromSuperview()
})

Answer 3

You are getting that error because there is no delete method in the imageView, but there is a method called removeFromSuperview.
You are going to remove the overlay from the SuperView
DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(1), execute: {
overlay.removeFromSuperview()
})
Or:
self.overlay.hidden = true
Or try the following if your reference to it was a strong reference, make sure to nil that strong reference:
overlay= nil
Or animate without using dispatchQueue:
UIView.animate(withDuration: 0.5, delay: 0.3, options: [.repeat, .curveEaseOut, .autoreverse], animations: {
self.overlay.alpha = 0
}, completion: nil)