Shift Swift Array

Question

Array of Colors

let colorArray = [
    UIColor.redColor(),
    UIColor.orangeColor(),
    UIColor.yellowColor(),
    UIColor.greenColor(),
    UIColor.blueColor()
]

The goal is to shift the array:

1. To start with a different color.
2. To preserve the circular order of colors.

Example #1

If we wanted to start with the orange color (the color at index 1 in the original array), the array would look like this:

let colorArray = [
    UIColor.orangeColor(),
    UIColor.yellowColor(),
    UIColor.greenColor(),
    UIColor.blueColor(),
    UIColor.redColor(),
]

Example #2

If we wanted to start with the green color (the color at index 3 in the original array), the array would look like this:

let colorArray = [
    UIColor.greenColor(),
    UIColor.blueColor(),
    UIColor.redColor(),
    UIColor.orangeColor(),
    UIColor.yellowColor()
]

Answer 1

I know this might be late. But the easiest way to rotate or shift an array is

func shifter(shiftIndex: Int) {
   let strArr: [String] = ["a","b","c","d"]
   var newArr = strArr[shiftIndex..<strArr.count]
   newArr += strArr[0..<shiftIndex]       
   println(newArr)  }

shifter(2) //[c, d, a, b] you can modify the function to take array as input