Up and down image view and vice versa Swift/iOS - ios

Question

For my personal project, I try to make an image of a leaf go up for 5 seconds and then lower it for 5 seconds.
It works well, only after raising and lowering the sheet, it changes position and is transported well to the bottom of the screen.
I would like it to go up from the place of the end of the descent. I have tried several things but nothing works. I wish I could restore the original position after descent but I think it will make the image flicker on the screen.
Any ideas ?
func upLeaf(){
let xPosition = imageLeaf.frame.origin.x
let yPosition = imageLeaf.frame.origin.y - 100 // Slide Up - 20px
let width = imageLeaf.frame.size.width
let height = imageLeaf.frame.size.height
UIView.animate(withDuration: 5.0, animations: {
self.imageLeaf.frame = CGRect(x: xPosition, y: yPosition, width: width, height: height)
})
}
func downLeaf(){
let xPosition = imageLeaf.frame.origin.x
let yPosition = imageLeaf.frame.origin.y + 100 // Slide Up - 20px
let width = imageLeaf.frame.size.width
let height = imageLeaf.frame.size.height
UIView.animate(withDuration: 5.0, animations: {
self.imageLeaf.frame = CGRect(x: xPosition, y: yPosition, width: width, height: height)
})
secondUp = true
}

Answer 1

Instead of using frame to perform the animation you could use CGAffineTransform. It's more powerful and equally easy:
UIView.animate(withDuration: 5.0, animations: {
line3.transform = CGAffineTransform(translationX: 0, y: 100)
})
When you want to return to the initial state you should type:
UIView.animate(withDuration: 5.0, animations: {
line3.transform = CGAffineTransform.identity
})
CGAffineTransform remembers the initial parameters for your view, so that you don't have to do any calculations yourself.

Answer 2

If you only want the leaf to go up and down, you can just animate imageLeaf's frame.origin.y (no need to keep track of origin.x, width, or height).
func upDownLeaf() {
UIView.animate(withDuration: 5.0, animations: {
self.imageLeaf.frame.origin.y -= 100 /// go up
}) { _ in
UIView.animate(withDuration: 5.0, animations: {
self.imageLeaf.frame.origin.y += 100 /// go down
})
}
}