CODEWITHSUNDEEP
swiftanimationuicolor
Pixele9
Pixele9

Reputation: 442

swift animation does not go through all keyframes

I want to go through red -> green -> blue, but when I add 3 colors, it just go through the last two colors: 

    var duration = 6.0

    UIView.animateKeyframesWithDuration(duration, delay: 1.0, options: UIViewKeyframeAnimationOptions.Repeat | UIViewKeyframeAnimationOptions.Autoreverse, animations: { () -> Void in
        self.colorTransition.backgroundColor = UIColor.redColor()
        self.colorTransition.backgroundColor = UIColor.greenColor()
        self.colorTransition.backgroundColor = UIColor.blueColor()

    }, completion: nil)

Upvotes: 1

Views: 1256

Answers (1)

Rob
Rob

Reputation: 437882

You have to call addKeyframe(withRelativeStartTime:relativeDuration:animations:) for each of the three transitions, specifying when they start (as percentages of the overall duration) and for how long (again, as percentages).

For example:

UIView.animateKeyframes(withDuration: duration, delay: 2, options: [.repeat, .autoreverse], animations: {
    UIView.addKeyframe(withRelativeStartTime: 0, relativeDuration: 0.33) {
        self.colorTransition.backgroundColor = .red
    }
    UIView.addKeyframe(withRelativeStartTime: 0.33, relativeDuration: 0.33) {
        self.colorTransition.backgroundColor = .green
    }
    UIView.addKeyframe(withRelativeStartTime: 0.66, relativeDuration: 0.34) {
        self.colorTransition.backgroundColor = .blue
    }
})

So, even though the total duration is 2 seconds, the relative start and duration values are percentages, values between 0 and 1.

Upvotes: 3

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