Error "NSMutableRLEArray objectAtIndex:effectiveRange:: Out of bounds'"

Question

I have the following code, in which I pass a string with of the type "Hello|r World|g" and the following function converts it into attributedString with "Hello" Being red in color and "World" being green in color. I used this as I am passing each of the strings in an array. The function only colors the text until it find a special character as shown in the condition during the end and then colors the text.

Code :

func formatAttributedString(string:String)->NSMutableAttributedString {
        var strCopy=string as NSString
        var color:UIColor=UIColor()
        var attributedString:NSMutableAttributedString!

        for var i:Int=0;i<strCopy.length-2;i++ {
            if (string[i] == "|") {
                println("|")
                var j:Int
                if string[i+1] == "r" {
                    color=UIColor(red: 249, green: 39, blue: 14, alpha: 1)
                    strCopy = strCopy.stringByReplacingOccurrencesOfString("|r", withString: "", options: NSStringCompareOptions.LiteralSearch, range: NSMakeRange(0, i + 2))
                    println("r")

                }
               else  if string[i+1] == "v" {
                    color=UIColor(red: 161, green: 153, blue: 249, alpha: 1)
                    strCopy = strCopy.stringByReplacingOccurrencesOfString("|v", withString: "", options: NSStringCompareOptions.LiteralSearch, range: NSMakeRange(0, i + 2))
                    println("v")

                }
                else if string[i+1] == "y" {
                    color=UIColor(red: 235, green: 223, blue: 145, alpha: 1)
                    strCopy = strCopy.stringByReplacingOccurrencesOfString("|y", withString: "", options: NSStringCompareOptions.LiteralSearch, range: NSMakeRange(0, i + 2))
                    println("y")
                }
                else if string[i+1] == "g" {
                    color=UIColor(red: 174, green: 227, blue: 79, alpha: 1)
                    strCopy = strCopy.stringByReplacingOccurrencesOfString("|y", withString: "", options: NSStringCompareOptions.LiteralSearch, range: NSMakeRange(0, i + 2))
                    println("g")
                }
                else if string[i+1] == "b" {
                    color=UIColor(red: 107, green: 224, blue: 240, alpha: 1)
                    strCopy = strCopy.stringByReplacingOccurrencesOfString("|b", withString: "", options: NSStringCompareOptions.LiteralSearch, range: NSMakeRange(0, i + 2))
                    println("b")
                }


                for j=i; j>=0;j-- {
                    if string[j] == " " || string[j] == "/" || string[j] == "." || string[j] == "\"" || string[j] == "\n" || string[j] == "<" || string[j] == "\t" || string[j] == "("{
                        println("/")
                        break

                    }
                }
                attributedString=NSMutableAttributedString(string: strCopy)
                attributedString.addAttribute("NSForegroundColorAttributeName", value: color, range: NSMakeRange(j, i-j))

            }
        }

I get the following error :

'NSMutableRLEArray objectAtIndex:effectiveRange:: Out of bounds'

As I have added printlns , | and r get printed. Please help,Thanks in advance.

It's not a duplicate of this question as | and r are getting printed.

Answer 1

I have tried to meet your function signature with another implementation using Swift's anonymous tuple and higher ordered functions. I did this as an exercise for myself and at the end thought it best to share.

func formatAttributedString(string: String) -> NSMutableAttributedString {
    // create a mapping between the attribute token and the corresponding UIColor
    let colors = [
        "|r": UIColor(red: 249/255, green:  39/255, blue:  14/255, alpha: 1.0),
        "|v": UIColor(red: 161/255, green: 153/255, blue: 249/255, alpha: 1.0),
        "|y": UIColor(red: 235/255, green: 223/255, blue: 145/255, alpha: 1.0),
        "|g": UIColor(red: 174/255, green: 227/255, blue:  79/255, alpha: 1.0),
        "|b": UIColor(red: 107/255, green: 224/255, blue: 240/255, alpha: 1.0)]

    // split argument into an array of (String, UIColor) tuples

    // default the array to the entire argument string with a black color
    var substrings = [(string, UIColor.blackColor())]

    for (token, color) in colors {
        substrings = substrings.flatMap {
            var substrings = $0.0.componentsSeparatedByString(token)
            let tail = (substrings.removeLast(), $0.1)   // tuple for trailing string at old color
            var result = substrings.map{($0, color)}     // array of tuples for strings at new color
            result.append(tail)
            return result
        }
    }
    // because we default the original string to black, there may be an empty string tuple at the end
    substrings = substrings.filter{(string, _) in return !string.isEmpty}

    // convert array of (String, UIColor) tuples into a single attributed string
    var result = reduce(substrings, NSMutableAttributedString(string: "")) {
        var string = NSAttributedString(string: $1.0, attributes: [NSForegroundColorAttributeName: $1.1])
        $0.appendAttributedString(string)
        return $0
    }
    return result
}