How can I fill the inside of a UIBezierPath with Swift?

Question

I am trying to fill a UIBezierPath using Swift 5 but when I try to run my function to color the paths, I get many errors. None of them are fatal so the build succeeds, but the path is not drawn on the screen. I am attaching the relevant code and two of the errors. Thanks in advance.

func colorPaths() {    
                let path = leftCorner //Where leftCorner isa UIBezierPath

                let fillColor = UIColor.white
                fillColor.setFill()

                path.lineWidth = 1.0
                let strokeColor = UIColor.blue
                strokeColor.setStroke()

                path.fill()
                path.stroke()
            }

Errors:

2020-05-25 14:35:26.653308-0400 StatsApTBD[50679:10052723] [Unknown process name] CGContextSetFillColorWithColor: invalid context 0x0. Backtrace:
  <$s10StatsApTBD8HeatViewC08changeToD4MapsyyF10colorPathsL_yyF+94>
   <$s10StatsApTBD8HeatViewC08changeToD4MapsyyF+5247>
    <$s10StatsApTBD8HeatViewC8addMarksyyF+626>
     <$s10StatsApTBD8HeatViewC21viewDidLayoutSubviewsyyF+7831>
      <$s10StatsApTBD8HeatViewC21viewDidLayoutSubviewsyyFTo+43>
       <-[UIView(CALayerDelegate) layoutSublayersOfLayer:]+3013>
        <-[CALayer layoutSublayers]+255>
         <_ZN2CA5Layer16layout_if_neededEPNS_11TransactionE+517>
          <_ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE+80>
           <_ZN2CA7Context18commit_transactionEPNS_11TransactionEd+324>
            <_ZN2CA11Transaction6commitEv+643>
             <_afterCACommitHandler+160>
              <__CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__+23>
               <__CFRunLoopDoObservers+430>
                <__CFRunLoopRun+1514>
                 <CFRunLoopRunSpecific+438>
                  <GSEventRunModal+65>
                   <UIApplicationMain+1621>
                    <main+75>
                     <start+1>                             1
2020-05-25 14:35:26.655966-0400 StatsApTBD[50679:10052723] [Unknown process name] CGContextSetStrokeColorWithColor: invalid context 0x0. Backtrace:
  <$s10StatsApTBD8HeatViewC08changeToD4MapsyyF10colorPathsL_yyF+175>
   <$s10StatsApTBD8HeatViewC08changeToD4MapsyyF+5247>
    <$s10StatsApTBD8HeatViewC8addMarksyyF+626>
     <$s10StatsApTBD8HeatViewC21viewDidLayoutSubviewsyyF+7831>
      <$s10StatsApTBD8HeatViewC21viewDidLayoutSubviewsyyFTo+43>
       <-[UIView(CALayerDelegate) layoutSublayersOfLayer:]+3013>
        <-[CALayer layoutSublayers]+255>
         <_ZN2CA5Layer16layout_if_neededEPNS_11TransactionE+517>
          <_ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE+80>
           <_ZN2CA7Context18commit_transactionEPNS_11TransactionEd+324>
            <_ZN2CA11Transaction6commitEv+643>
             <_afterCACommitHandler+160>
              <__CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__+23>
               <__CFRunLoopDoObservers+430>
                <__CFRunLoopRun+1514>
                 <CFRunLoopRunSpecific+438>
                  <GSEventRunModal+65>
                   <UIApplicationMain+1621>
                    <main+75>
                     <start+1>                             1

Answer 1

Create a CAShapeLayer and set the path for the same like below.

let width: CGFloat = 200
let height: CGFloat = 200

let shapeLayer = CAShapeLayer()
shapeLayer.frame = CGRect(x: 0, y: 0, width: width, height: height)

let path = leftCorner
shapeLayer.path = path
shapeLayer.strokeColor = UIColor.blue.cgColor
shapeLayer.fillColor = UIColor.white.cgColor

Then add the above shapeLayer to your view.

yourView.layer.addSublayer(shapeLayer)

That should get your path to show on screen.