Hide view in iOS and rearrange other view with fullscreen - swift

Question

Let's assume I have this layout design on an iPhone Portrait.
A Label (red) and an Image (blue).
But I would like to have it this way when the iPhone is in landscape. Only the image (blue).
I trying with following code but the label does not appear after return back to portrait:
override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
coordinator.animate(alongsideTransition: { (UIViewControllerTransitionCoordinatorContext) -> Void in
let orient = UIDevice.current.orientation
switch orient {
case .portrait:
print("Portrait")
let ctop = NSLayoutConstraint(item: self.imageView, attribute: .top, relatedBy: .equal, toItem: self.view, attribute: .top, multiplier: 1, constant: 44)
self.view.removeConstraint(ctop)
self.labelView.isHidden = false
break
default:
print("LandScape")
let ctop = NSLayoutConstraint(item: self.imageView, attribute: .top, relatedBy: .equal, toItem: self.view, attribute: .top, multiplier: 1, constant: 0)
self.view.addConstraint(ctop)
self.labelView.isHidden = true
break
}
}, completion: { (UIViewControllerTransitionCoordinatorContext) -> Void in
print("rotation completed")
})
}

Answer 1

You have a mixup with your addConstraint/removeConstraint logic. In the Portrait case you define a new cTop constraint and remove it (!?!) from the view - you probably want to add it.
It would be better to define both constraints right away when you create your views, and only set one to active - and then switch the isActive setting on both according to your new orientation. Or only define one constraint and just change the constant on it accordingly.