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iOS Build a Simple iPhone App with Swift Creating a Data Model Finishing Up Our Model

LUIS A HERNANDEZ PIÑA M
LUIS A HERNANDEZ PIÑA M
2,223 Points
Posted by LUIS A HERNANDEZ PIÑA M
LUIS A HERNANDEZ PIÑA M
2,223 Points

In the random facts generator I did what was shown in the video, but I get: fatal error: Array index out of range.

func randomFact() -> String {
        var unsignedArrayCount = UInt32(factsArray.count)
        var usignedRandomNumber = arc4random_uniform(unsignedArrayCount)
        var randomNumber = Int(unsignedArrayCount)

        return factsArray[randomNumber]

// I did the same as in the video however I get fatal error: index out of range. How can the index be out of range if it is set to factsArray.count?

1 Answer

Andrew Shook
Andrew Shook
31,709 Points
Andrew Shook
Andrew Shook
31,709 Points

you are not type casting the correct variable. See below:

func randomFact() -> String {
        var unsignedArrayCount = UInt32(factsArray.count)
        var usignedRandomNumber = arc4random_uniform(unsignedArrayCount)
        // your original code 
        // var randomNumber = Int(unsignedArrayCount)

        //what the code needs to be
        var randomNumber = Int(usignedRandomNumber)

        return factsArray[randomNumber]