CODEWITHSUNDEEP
iosxcodecolors
Entwiker Defoe
Entwiker Defoe

Reputation: 11

How to select a random color in Swift

I have this little bit of code in which it selects some colors, I would like to know what if I wanted to select a random color between these ones under the code, how could I do that ?

extension UIColor {
    static var random: UIColor {
        return UIColor(red: .random(in: 0...2), green: .random(in: 0...2), blue: .random(in: 0...2), alpha: 1.0)
    }
}

Colors I would like to pick in my extension

enter image description here

Upvotes: 0

Views: 3915

Answers (3)

PGDev
PGDev

Reputation: 24341

To get a random color from a list of UIColors, just call randomElement() on the collection of UIColor elements, i.e.

extension UIColor {
    static func random(from colors: [UIColor]) -> UIColor? {
        return colors.randomElement()
    }
}

You can use it like:

let randomColor = UIColor.random(from: [.red, .yellow, .green, .blue, .purple])

I've used the sample colors here. Use your own specific colors that you want to use.

In case you have colors in the form of hex values, you need to add another method in the extension to convert that hex value into UIColor instance.

Let me know in case of any issues.

Upvotes: 1

Kuldeep
Kuldeep

Reputation: 4552

If you want to use only the colours that you added in your question then add your required colour hex string in Array.

let arrColors = ["ff0000", "228B22", "FFFF00", "800080", "ffa500"] // Use your color hex

Now you need to pick random object from above array like this.

let randomIndex = Int(arc4random_uniform(UInt32(arrColors.count)))
self.vwNavigationBar.backgroundColor = self.hexStringToUIColor(hex: arrColors[randomIndex])

Function to convert Hex string to Color

func hexStringToUIColor (hex:String) -> UIColor {
    var cString:String = hex.trimmingCharacters(in: .whitespacesAndNewlines).uppercased()

    if (cString.hasPrefix("#")) {
        cString.remove(at: cString.startIndex)
    }

    if ((cString.count) != 6) {
        return UIColor.gray
    }

    var rgbValue:UInt32 = 0
    Scanner(string: cString).scanHexInt32(&rgbValue)

    return UIColor(
        red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
        green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
        blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
        alpha: CGFloat(1.0)
    )
}

Upvotes: 2

Jay Patel
Jay Patel

Reputation: 353

Try this. It should work.

 extension UIColor {

     static func random() -> UIColor {
        return UIColor.rgb(CGFloat.random(in: 0..<256), green: CGFloat.random(in: 0..<256), blue: CGFloat.random(in: 0..<256))
     }

     static func rgb(_ red: CGFloat, green: CGFloat, blue: CGFloat) -> UIColor {
      return UIColor(red: red/255, green: green/255, blue: blue/255, alpha: 1)
     }

     convenience init(red: Int, green: Int, blue: Int) {
        assert(red >= 0 && red <= 255, "Invalid red component")
        assert(green >= 0 && green <= 255, "Invalid green component")
        assert(blue >= 0 && blue <= 255, "Invalid blue component")

        self.init(red: CGFloat(red) / 255.0, green: CGFloat(green) / 255.0, blue: CGFloat(blue) / 255.0, alpha: 1.0)
     }

     convenience init(rgb: Int) {
        self.init(
          red: (rgb >> 16) & 0xFF,
          green: (rgb >> 8) & 0xFF,
          blue: rgb & 0xFF
       )
      }

    static func getColor() -> UIColor {
       let chooseFrom = [0x064545,0x708545,0x45580] //Add your colors here
       return UIColor.init(rgb: chooseFrom[Int.random(in: 0..<chooseFrom.count)])
     }

   }

Upvotes: 1

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