iosswiftuicolorrgbacgcolor

Using UIColor with CAShapeLayer

I'm passing an RGB color to shapeLayer.fillColor and shapeLayer.strokeColor, and my code is crashing. Here's what I tried:

let shapeLayer = CAShapeLayer()
shapeLayer.fillColor = (UIColor(red: 57, green: 65, blue: 101, alpha: 1) as! CGColor)
shapeLayer.strokeColor = (UIColor(red: 57, green: 65, blue: 101, alpha: 1) as! CGColor)

If I write my RGB color as:

UIColor(red: 57, green: 65, blue: 101, alpha: 1)

Xcode gives me a warning to change it to:

(UIColor(red: 57, green: 65, blue: 101, alpha: 1) as! CGColor)

error

When I run Xcode's suggested fix, my app crashes. Why?

Solution

  • First of all the parameters red,green, blue and alpha must be in range from 0.0 to 1.0

    Secondly, you must pass the cgColor to CGLayer, e.g. 

    let color = UIColor(red: 57.0/255.0, green: 65.0/255.0, blue: 101.0/255.0, alpha: 1)
shapeLayer.fillColor = color.cgColor
shapeLayer.strokeColor = color.cgColor