How to force update to render continuous path - ios

Question

i'm currently working on continuous animation on path. The Path should be updated with new values periodically and update should trigger start of new animation with those values. I'm having a problem while trying to refresh view with new values. The animation with path is shown at start with animation and after trying to trigger view update from method it's not showing any new view or updated path. Just white screen. My code for this view and updating is:
The chart view wrapped into UIViewRepresentable:
struct AnimatedChartView: UIViewRepresentable {
let geometryProxy: GeometryProxy
let leadValues: [Float]//Binding<[Float]>
//Chart control values
//step coefficinet
let xStepCoefficient: CGFloat = 0.00035
//Single step on view
var xStep: CGFloat{
let xStepValue = xStepCoefficient * geometryProxy.frame(in: .local).width
return xStepValue
}
var rootView: UIView
var chartLayer: CAShapeLayer
//Make chart view with animation
func makeUIView(context: Context) -> some UIView {
//Prepare view for animation and chart
chartLayer.delegate = context.coordinator
rootView.layer.addSublayer(chartLayer)
return rootView
}
init(geometry: GeometryProxy, values: [Float]) {
rootView = UIView()
geometryProxy = geometry
leadValues = values
chartLayer = CAShapeLayer()
chartLayer = prepareAnimationLayer()
}
//Update viewu
func updateUIView(_ uiView: UIViewType, context: Context) {
print("Update uiView")
DispatchQueue.main.async {
let newChartLayer = prepareAnimationLayer()
rootView.layer.addSublayer(newChartLayer)
rootView.setNeedsDisplay()
}
}
//Assign
func makeCoordinator() -> Coordinator {
Coordinator(self)
}
//Delegates from view
class Coordinator: NSObject, CALayerDelegate {
var parent: AnimatedChartView
init(_ parentView: AnimatedChartView) {
self.parent = parentView
}
func draw(_ layer: CALayer, in ctx: CGContext) {
print("Drawing layer in context")
}
func layerWillDraw(_ layer: CALayer) {
print("layer will draw")
}
}
//Assign animation layer for chart
private func prepareAnimationLayer() -> CAShapeLayer {
//Create animation proeprties
let chartLayer = CAShapeLayer()
let strokeAnimation = makeAnimation()
let chartPath = makeChartFromValues(newValues: leadValues)
//Assign path and marks start and end of stroke to animate
chartLayer.path = chartPath.cgPath
chartLayer.strokeStart = 0.0
chartLayer.strokeEnd = 0.0
chartLayer.strokeColor = UIColor.green.cgColor
chartLayer.lineWidth = 2
chartLayer.fillColor = UIColor.clear.cgColor
chartLayer.add(strokeAnimation, forKey: "strokeAnimation")
return chartLayer
}
//Setup chart animation
private func makeAnimation() -> CABasicAnimation{
let strokeEndAnimation = CABasicAnimation(keyPath: "strokeEnd")
//Prepare animation
strokeEndAnimation.fromValue = 0.0
strokeEndAnimation.toValue = 1.0
strokeEndAnimation.duration = 1
strokeEndAnimation.timingFunction = CAMediaTimingFunction(name: .easeInEaseOut)
strokeEndAnimation.repeatCount = 0
strokeEndAnimation.duration = 1
return strokeEndAnimation
}
//makes chart path
private func makeChartFromValues(newValues: [Float]) -> UIBezierPath{
let chartPath = UIBezierPath(roundedRect: CGRect(origin: .zero, size: .init(width: 200, height: 120)), byRoundingCorners: .allCorners, cornerRadii: .zero)
chartPath.move(to: .zero)
var currentX = xStep
newValues.forEach{ value in
//Value point to draw
let nextPoint = CGPoint(x: currentX, y: CGFloat(value / 1000))
//Adds line to chart
chartPath.addLine(to:nextPoint)
//Move to next value
currentX += xStep
}
return chartPath
}
}
and view function with viewmodel with timer which updates the values
struct UIKitAnimatedPathView: View {
#State var animationRect: CGRect = CGRect(origin: .zero, size: CGSize(width: 200, height: 200))
#StateObject var viewModel = AnimationViewModel()
var body: some View {
GeometryReader{ geo in
VStack(content: {
ForEach(0 ..< 18, id: \.self){ i in
AnimatedChartView(geometry: geo, values: viewModel.values)
}
})
}
}
}
Viewmodel:
class AnimationViewModel: ObservableObject{
#Published var values: [Float] = [Float](repeating: 1, count: 2000)
#Published var timer: Timer?
init() {
timer = Timer.scheduledTimer(withTimeInterval: 1, repeats: true, block: {time in
//print("time in: \(time.timeInterval)")
var vals:[Float] = []
for _ in 0 ..< 2000{
let rand = Float.random(in: -20000 ..< 0)
vals.append(rand)
}
self.values.removeAll()
self.values = vals
})
}
}
You can see commented out some part of code as i was trying to make it work somehow but with no luck so far... The functionality i want to achive is continuously updating chart. This code works for first run. Thank you in advance for any guidence on how to make it working :))