随机选择一个出口并设置其他出口

Question

我有一个函数，它随机选择一个UIButton并将其字符设置为某个表情符号。现在我想将剩余的UIButtons设置为随机表情符号。

我如何确定哪些UIButtons没有从随机生成器设置一个值?

我还想确保被分配的值与在随机生成器中插入的值不同。

@IBOutlet weak var topLeftAnswer: UIButton!
@IBOutlet weak var topRightAnswer: UIButton!
@IBOutlet weak var bottomLeftAnswer: UIButton!
@IBOutlet weak var bottomRightAnswer: UIButton!
 func correctAnswerGen() {
    var correct: UInt32 = arc4random_uniform(4)
    switch correct{
    case 0: topLeftAnswer.setTitle("😄", forState: UIControlState.Normal)
    case 1: topRightAnswer.setTitle("😄", forState: UIControlState.Normal)
    case 2: bottomLeftAnswer.setTitle("😄", forState: UIControlState.Normal)
    case 3: bottomRightAnswer.setTitle("😄", forState: UIControlState.Normal)
    default: break
    }
    //assign other 3 buttons to another emoji value.
}

Answer 1

同样的道理:

func randomEmoji() -> String{
    let emojies = [UInt32](0x1F601...0x1F64F)
    + [UInt32](0x2702...0x27B0)
    + [UInt32](0x1F680...0x1F6C0)
    + [UInt32](0x1F170...0x1F251)
    let rand = Int(arc4random_uniform(UInt32(emojies.count - 1)))
    return String(UnicodeScalar(emojies[rand]))
}

Answer 2

设置一个随机的表情符号，可以通过循环0x1F601...0x1F64F，选择一个随机的表情符号，如:

var rand: UInt32 = arc4random_uniform(78)
for i in 0x1F601...0x1F64F {
    if rand == i {
          var c = String(UnicodeScalar(i))
          print(c)
          break
    }
}

但是由于有更多的表情符号，你必须使用像这样的东西来循环遍历所有的表情符号:

let allEmojis = [
    0x1F601...0x1F64F,
    0x2702...0x27B0,
    0x1F680...0x1F6C0,
    0x1F170...0x1F251
]
var rand: UInt32 = arc4random_uniform(544)
var counter = 0
for range in allEmojis {
    for i in range {
        if rand == counter
        {
            var c = String(UnicodeScalar(i))
            print(c)
        }
        counter++
    }
}