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swiftswift2animatewithdurationswift3optionsettype

Whats the Swift animate WithDuration syntax?


I'm porting an older app over to Xcode 7 beta and I'm getting an error on my animations:

Cannot invoke 'animateWithDuration' with an argument list of type '(Double, delay: Double, options: nil, animations: () -> _, completion: nil)'

Here's the code:

 UIView.animateWithDuration(0.5, delay: 0.3, options: nil, animations: {
      self.username.center.x += self.view.bounds.width
    }, completion: nil)

This works in Xcode 6 so I'm assuming this is an update in Swift. So my question is:

What's the Swift 3 syntax for animateWithDuration?


Solution

  • Swift 3/4 Syntax

    Here's an update with the Swift 3 Syntax:

    UIView.animate(withDuration: 0.5, delay: 0.3, options: [.repeat, .curveEaseOut, .autoreverse], animations: {
        self.username.center.x += self.view.bounds.width
    }, completion: nil)
    

    If you need to add a completion handler just add a closure like so:

    UIView.animate(withDuration: 0.5, delay: 0.3, options: [.repeat, .curveEaseOut, .autoreverse], animations: {
        // animation stuff      
    }, completion: { _ in
        // do stuff once animation is complete
    })
    

    Old Answer:

    It turns out it's a very simple fix, just change options: nil to options: [].

    Swift 2.2 Syntax:

    UIView.animateWithDuration(0.5, delay: 0.3, options: [], animations: {
          self.username.center.x += self.view.bounds.width
        }, completion: nil)
    

    What changed?

    Swift 2 got rid of the C-Style comma-delimited list of options in favor of option sets (see: OptionSetType). In my original question, I passed in nil for my options, which was valid prior to Swift 2. With the updated syntax, we now see an empty option list as an empty set: [].

    An example of animateWithDuration with some options would be this:

     UIView.animateWithDuration(0.5, delay: 0.3, options: [.Repeat, .CurveEaseOut, .Autoreverse], animations: {
          self.username.center.x += self.view.bounds.width
        }, completion: nil)