ios - 如何随机化我的 ImageView ？

Question

每次按下按钮时我都想要一个与当前不同的随机图像

这是我使用的代码，但有时图像没有更新:

    @IBAction func nextBarButton(sender: UIBarButtonItem) {


    var image1 = UIImage(named: "RedBalloon1.jpg")
    var image2 = UIImage(named: "RedBalloon2.jpg")
    var image3 = UIImage(named: "RedBalloon3.jpg")
    var image4 = UIImage(named: "RedBalloon4.jpg")

    var images = [image1, image2, image3, image4]
    var indexPath = Int(arc4random_uniform(UInt32(images.count)))
    currentIndex = indexPath
    if currentIndex == indexPath {
        indexPath = Int(arc4random_uniform(UInt32(images.count)))
    }

    self.imageView.image = images[indexPath]
    self.balloonLabel.text = "\(count++) Balloon"


}

Answer 1

嗯，因为这条线

currentIndex = indexPath

下一行总是返回true:

if currentIndex == indexPath {

所以下一行设置了indexPath

indexPath = Int(arc4random_uniform(UInt32(images.count)))

并且它有四分之一的机会等于当前选择的图像。

你需要一个 do-while loop , 以确保根据需要选择新的随机数:

var images = [image1, image2, image3, image4]
var indexPath = 0
do {
    indexPath = Int(arc4random_uniform(UInt32(images.count)))
} while currentIndex == indexPath

之后可以设置currentIndex = indexPath。