相关疑难解决方法(0)

我有以下数组:

var notebookCovers = ["cover1", "cover2", "cover3", "cover4", "cover4", "cover6", "cover7", "cover8", "cover9", "cover10"]

并且UIButton当它被按下时,它会生成一个UIImage带有数组元素的新元素.

我需要做的是每次按下按钮以从数组中生成随机但唯一的元素(不重复元素),直到它们全部被选中,然后再次重新启动数组.

到目前为止,我有一个随机元素,但它重复,我无法弄清楚如何它,所以它每次都获得一个独特的图像

func createNewNotebook() {
    let newNotebook = Notebook()
    let randomInt = randomNumber()
    newNotebook.coverImageString = notebookCovers[randomInt]
    notebooks.insert(newNotebook, at: 0)
    collectionView.reloadData()
}

func randomNumber() -> Int {
    var previousNumber = arc4random_uniform(UInt32(notebookCovers.count))   
    var randomNumber = arc4random_uniform(UInt32(notebookCovers.count - 1)) 
    notebookCovers.shuffle()
    if randomNumber == previousNumber {
        randomNumber = UInt32(notebookCovers.count - 1)
    }
    previousNumber = randomNumber
    return Int(randomNumber)
}