UIView.animate works fine in viewDidAppear() but fires instantly anywhere else - swift

Question

I have looked and tried every solution I could find online as to why my animations is not properly firing. DISCLOSURE: they work fine when put in viewDidAppear(). This question has been asked countless times but none of the solutions work. The results of the animations appear but not with the delay specified, they are instant. What I would like is to fade in a my requestRideButton in and out using either isHidden with UIView.transition or alpha with UIView.animate.
I would also like to move the button while it is fading. I have tried every combination of self.view.layoutIfNeeded() both in and out the animate closure with the constraint in and out. I have also tried it with self.view.superview?.layoutIfNeeded()
class RideRequestViewController: UIViewController, MKMapViewDelegate {
#IBOutlet weak var rideRequestBottomButtonConstraint: NSLayoutConstraint!
#IBOutlet weak var rideRequestButtonTopConstraint: NSLayoutConstraint!
// Views
#IBOutlet var mapView: MKMapView!
#IBOutlet var rideDetailsView: UIView!
#IBOutlet var requestRideButton: UIButton!
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
// Layout map view to fill screen
mapView.frame = view.bounds
// Apply corner radius and shadow styling to floating views
let cornerRadius: CGFloat = 5.0
inputContainerView.layoutCornerRadiusAndShadow(cornerRadius: cornerRadius)
originButton.layoutCornerRadiusMask(corners: [.topLeft, .topRight], cornerRadius: cornerRadius)
paymentButton.layoutCornerRadiusMask(corners: .bottomLeft, cornerRadius: cornerRadius)
priceButton.layoutCornerRadiusMask(corners: .bottomRight, cornerRadius: cornerRadius)
rideDetailsView.layoutCornerRadiusAndShadow(cornerRadius: cornerRadius)
pilotView.layoutCornerRadiusMask(corners: [.topLeft, .bottomLeft], cornerRadius: cornerRadius)
vehicleView.layoutCornerRadiusMask(corners: [.topRight, .bottomRight], cornerRadius: cornerRadius)
requestRideButton.layoutCornerRadiusAndShadow(cornerRadius: cornerRadius)
}
override func viewDidLoad() {
ref = Database.database().reference()
}
func animate() {
self.rideRequestButtonTopConstraint.constant = -44
UIView.animate(withDuration: 1) {
self.view.layoutIfNeeded()
}
}
#IBAction
private func handleRequestRideButtonTapped() {
switch rideRequestState {
case .none:
// Update to requesting state
rideRequestState = .requesting
// Perform payment request
paymentContext.requestPayment()
case .requesting:
// Do nothing
// Show button
break
case .active:
// Complete the ride
completeActiveRide()
}
}
private func reloadRequestRideButton() {
guard originPlacemark != nil && destinationPlacemark != nil && paymentContext.selectedPaymentMethod != nil else {
// Show disabled state
requestRideButton.backgroundColor = .riderGrayColor
requestRideButton.setTitle("CONFIRM DELIVERY", for: .normal)
requestRideButton.setTitleColor(.black, for: .normal)
requestRideButton.setImage(nil, for: .normal)
requestRideButton.isEnabled = false
return
}
animate() // <--- view just disappears instantly instead
switch rideRequestState {
case .none:
// Show enabled state
requestRideButton.backgroundColor = .riderYellowColor
requestRideButton.setTitle("CONFIRM DELIVERY", for: .normal)
requestRideButton.setTitleColor(.black, for: .normal)
requestRideButton.setImage(nil, for: .normal)
requestRideButton.isEnabled = true
case .requesting:
// Show loading state
requestRideButton.backgroundColor = .riderYellowColor
requestRideButton.setTitle("...", for: .normal)
requestRideButton.setTitleColor(.white, for: .normal)
requestRideButton.setImage(nil, for: .normal)
requestRideButton.isEnabled = false
case .active:
// Show completion state
requestRideButton.backgroundColor = .white
requestRideButton.setTitle("Complete Ride", for: .normal)
requestRideButton.setTitleColor(.riderDarkBlueColor, for: .normal)
requestRideButton.setImage(nil, for: .normal)
requestRideButton.isEnabled = true
}
}

Answer 1

Changes to views to be animated should be inside the animate block.
func animate() {
UIView.animate(withDuration: 1) {
self.rideRequestButtonTopConstraint.constant = -44
self.view.layoutIfNeeded()
}
}
Changing the constraint in the line above will just update a value and move the view. It won't animate it
UPDATE
So based on looking at another answer and some additional research, The author of UIKit suggests that we update constraints and call layoutIfNeeded inside the animation block like above.
Here is the playground I used to test it
import UIKit
import PlaygroundSupport
class ViewController: UIViewController {
let movableView = UIView()
var topConstraint: NSLayoutConstraint?
override func viewDidLoad() {
super.viewDidLoad()
let button = UIButton(frame: CGRect(x: 0, y: 0, width: 50, height: 50))
view.addSubview(button)
button.setTitle("Animate", for: .normal)
button.addTarget(self, action: #selector(animate), for: .touchUpInside)
view.addSubview(movableView)
movableView.backgroundColor = .red
movableView.translatesAutoresizingMaskIntoConstraints = false
topConstraint = NSLayoutConstraint(item: movableView, attribute: .top, relatedBy: .equal, toItem: view, attribute: .top, multiplier: 1.0, constant: 100)
topConstraint?.isActive = true
NSLayoutConstraint(item: movableView, attribute: .leading, relatedBy: .equal, toItem: view, attribute: .leading, multiplier: 1.0, constant: 0).isActive = true
NSLayoutConstraint(item: movableView, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 100).isActive = true
NSLayoutConstraint(item: movableView, attribute: .width, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: 100).isActive = true
}
#objc func animate() {
UIView.animate(withDuration: 4.0, animations: {
self.topConstraint?.constant = -100
self.view.layoutIfNeeded()
})
}
}
let vc = ViewController()
PlaygroundPage.current.liveView = vc.view