UIView fill animation in iOS Swift? - ios

Question

I want to fill the color of view from left to right as fill animation. I have been using this code to get the effect but somehow it doesn't show any animation.i am using below code.
UIView.animate(withDuration: 2.0, delay: 0.2, options:.curveLinear, animations: {
view!.backgroundColor = Constant.AppColor.viewBottomFocus
}, completion:nil)
please tell me how can i achieve this?

Answer 1

I don't think you can fill a color with left to right animation with simple UIView blocks. You can ofcourse change width or trailing constraint of the view and it will appear that the view is changing its color. But, I dont think thats the ideal way to do it.
To achieve what you want I guess you have to use gradient layer and animate the locations:
class AnimatingV:UIView {
func animate() {
let layer = CAGradientLayer()
let startLocations = [0, 0]
let endLocations = [1, 2]
layer.colors = [UIColor.red.cgColor, UIColor.white.cgColor]
layer.frame = self.frame
layer.locations = startLocations as [NSNumber]
layer.startPoint = CGPoint(x: 0.0, y: 1.0)
layer.endPoint = CGPoint(x: 1.0, y: 1.0)
self.layer.addSublayer(layer)
let anim = CABasicAnimation(keyPath: "locations")
anim.fromValue = startLocations
anim.toValue = endLocations
anim.duration = 2.0
layer.add(anim, forKey: "loc")
layer.locations = endLocations as [NSNumber]
}
}
let animatingV = AnimatingV(frame: CGRect(x: 0, y: 0, width: 400, height: 400))
animatingV.backgroundColor = UIColor.yellow
animatingV.animate()
PlaygroundPage.current.liveView = animatingV

Answer 2

Create UIView in storyboard and make its subclass of UIProgressView
then use this code to fill view , you can use animated fill as well by calling this function in scheduler
//progressView is view that you have create in storyboard
progressView.progress = .25; // .25 is the fill rate of total view
progressView.trackTintColor = [UIColor whiteColor];
progressView.progressTintColor = [UIColor redColor];