NEW: Subscribe to Hacking with Swift+ and accelerate your learning! >>

How to animate views using animate(withDuration:)

Swift version: 5.2

Paul Hudson    @twostraws   

Animation in iOS is done by starting an animation block, then telling iOS what changes you want to make. Because the animation block is active, those changes won't happen straight away – instead, iOS will execute them smoothly over the time you specified, so you don't have to worry when it will finish or what all the intermediate states are.

Here's a basic example to make a view fade out:

let viewToAnimate = UIView()

UIView.animate(withDuration: 1) {
    viewToAnimate.alpha = 0
}

If you want to remove the view from its superview once the fade has finished, you can use a more advanced version of the same method that gives you a completion block – a closure that will be run once the animation finishes. Here's how that looks:

UIView.animate(withDuration: 1, animations: {
    viewToAnimate.alpha = 0
}) { _ in
    viewToAnimate.removeFromSuperview()
}

You can also specify a delay before the animation starts, and even control the acceleration and deceleration curves of the animation, like this:

UIView.animate(withDuration: 1, delay: 1, options: .curveEaseIn, animations: {
    viewToAnimate.alpha = 0
}) { _ in
    viewToAnimate.removeFromSuperview()
}

Subscribe to Hacking with Swift+

Sponsor Hacking with Swift and reach the world's largest Swift community!

Available from iOS 4.0

Similar solutions…

About the Swift Knowledge Base

This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.

BUY OUR BOOKS
Buy Pro Swift Buy Swift Design Patterns Buy Testing Swift Buy Hacking with iOS Buy Swift Coding Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift (Vapor Edition) Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Advanced iOS Volume Three Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with macOS Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Server-Side Swift (Kitura Edition) Buy Beyond Code

Was this page useful? Let us know!

Average rating: 4.9/5

Link copied to your pasteboard.