Swift Continuous Rotation Animation not so continuous

Question

Here is my code. Intent is to continuously rotate the UIImageView named swirls[l]. However, there is a small pause between every rotation start/end. I have gone through every single animation tutorial but cant figure out what the mistake is?

let fullRotation = CGFloat(M_PI * 2)

    let duration = 2.0
    let delay = 0.0
    let options = UIViewKeyframeAnimationOptions.Repeat | UIViewKeyframeAnimationOptions.CalculationModeLinear

    UIView.animateKeyframesWithDuration(duration, delay: delay, options: options, animations: {
        UIView.addKeyframeWithRelativeStartTime(0, relativeDuration: 1/3, animations: {
            swirls[l].transform = CGAffineTransformMakeRotation(1/3 * fullRotation)
        })
        UIView.addKeyframeWithRelativeStartTime(1/3, relativeDuration: 1/3, animations: {
            swirls[l].transform = CGAffineTransformMakeRotation(2/3 * fullRotation)
        })
        UIView.addKeyframeWithRelativeStartTime(2/3, relativeDuration: 1/3, animations: {
            swirls[l].transform = CGAffineTransformMakeRotation(3/3 * fullRotation)
        })

        }, completion: {finished in 
    })

EDIT: I see that it has been suggested that a previous solution is available, but it simply does not work for continuous uninterrupted rotation. The only trick that worked for me is the answer that I chose below. Thanks

possible duplicate of [Create a continuously rotating square on the screen using animateKeyframesWithDuration](http://stackoverflow.com/questions/26665124/create-a-continuously-rotating-square-on-the-screen-using-animatekeyframeswithdu) — Zell B., Mar 10 '15 at 17:29

score 56 · Answer 1 · edited Oct 16 '17 at 12:54

56

Try below extension for swift 4.

extension UIView {
    func rotate360Degrees(duration: CFTimeInterval = 3) {
        let rotateAnimation = CABasicAnimation(keyPath: "transform.rotation")
        rotateAnimation.fromValue = 0.0
        rotateAnimation.toValue = CGFloat(Double.pi * 2)
        rotateAnimation.isRemovedOnCompletion = false
        rotateAnimation.duration = duration
        rotateAnimation.repeatCount=Float.infinity
        self.layer.add(rotateAnimation, forKey: nil)
    }
}

For start rotation.

MyView.rotate360Degrees()

And for Stop.

MyView.layer.removeAllAnimations()

You can use UIButton, UILabel and many more.

edited Oct 16 '17 at 12:54

wm.p1us

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answered Dec 15 '16 at 09:02

Keval Vadoliya

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I love it! Honestly this should be the right answer. – CodyMace Jan 30 '17 at 15:49
Thanks for this answer! Worked like a charm... :) – iGatiTech Apr 27 '18 at 09:50
This solution is great, makes your VC less messy – A. Petrizza May 29 '18 at 22:55
1

Perfect, I tried different solutions but this is the best. – Matthijs Dec 04 '18 at 15:27

score 19 · Accepted Answer · edited Jul 24 '19 at 09:20

19

I'm not sure what's wrong with your code, but I've implemented continuous rotation using this method,

@IBAction func rotateView(sender: UIButton) {
    UIView.animate(withDuration: 0.5, delay: 0, options: .curveLinear, animations: { () -> Void in
        self.spinningView.transform = self.spinningView.transform.rotated(by: .pi / 2)
    }) { (finished) -> Void in
        self.rotateView(sender: sender)
    }
}

edited Jul 24 '19 at 09:20

Karen Hovhannisyan

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answered Mar 10 '15 at 15:53

rdelmar

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I think it would be better to use UIViewAnimationOptions.Repeat rather then starting animation again in completion handler – Zell B. Mar 10 '15 at 15:59
2

@zellb, that doesn't work in this situation since I'm only going 1/4 of the way around with each call. Besides, that's what the OP is doing, and it results in a delay before the next animation starts. – rdelmar Mar 10 '15 at 16:01
@rdelmar: I tried this but I get no rotation at all. – Kashif Mar 11 '15 at 22:18
@TPos, I don't know why that would be without seeing how you implemented it. It works fine in my hands. – rdelmar Mar 11 '15 at 23:25
@rdelmar: Actually your method does work!! I had initially made a typo. – Kashif Mar 11 '15 at 23:52
I did exactly same thing except the "options: .curveLinear" part which actually did the trick. – Artin Feb 18 '22 at 20:37

Pragnesh Vitthani · Answer 3 · 2018-08-03T05:15:59.370

If you want to continuous rotate Button or View and stop that rotation whenever you want then you can try this: For start rotation:

@IBOutlet weak var RotateBtn: UIButton!
var timeTimer: Timer?

viewDidLoad()
{
  self.rotateView()
  timeTimer = Timer.scheduledTimer(timeInterval: 0.5, target: self, selector: #selector(self.rotateView), userInfo: nil, repeats: true)
}

func rotateView()
{
    UIView.animate(withDuration: 0.5, delay: 0, options: .curveLinear, animations: { () -> Void in
        self.RotateBtn.transform = self.RotateBtn.transform.rotated(by: CGFloat(M_PI_4))
    })
}

If you want to stop rotation then use:

@IBAction func StopBtn_Pressed(_ sender: AnyObject)
{
   timeTimer?.invalidate()
   self.RecordBtn.layer.removeAllAnimations()
}

Swift Continuous Rotation Animation not so continuous

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