Swift 3 UIPickerView以编程方式开始旋转

Question

我正在使用Swift 3在iOS中创造某种命运。我使用了带有UIPickerView的库，我自定义了视图，使行无休止（因此，用户认为他可以滚动查看无休止的项目）。

唯一的问题是用户可以通过命运之轮缓慢地滑动价格，因此基本上他可以选择自己想要的任何价格。

尽管要防止这种情况发生，但是无论何时用户点击或滑动方向盘，我都会使UIPickerView旋转，并使用一个随机数来确定命运之轮的结果。

我知道如何向方向盘添加手势识别器，但是我唯一不知道的是如何以编程方式启动UIPickerView。

提前致谢！

Answer 1

我认为您正在寻找：

pick.selectRow(10, inComponent: 0, animated: true)

但是，如果您想查看完整的示例，我为您做了。

class ViewController: UIViewController, UIPickerViewDataSource{

@IBOutlet var pick: UIPickerView!

var myArr = [Int]()

var myT = Timer()

override func viewDidLoad() {
    super.viewDidLoad()

    for element in 0...100 {

        myArr.append(element)
        }


    myT = Timer.scheduledTimer(timeInterval: 3, target: self, selector: #selector(ViewController.movePicker), userInfo: nil, repeats: true)



}



 //MARK: - move picker

func movePicker()  {


    let position = Int(arc4random_uniform(89) + 10)


    pick.selectRow(position, inComponent: 0, animated: true)
    pick.showsSelectionIndicator = true

    if position == 50 || position == 72 || position == 90 || position == 35  {

        myT.invalidate()

        let alert = UIAlertController(title: "You Won!!", message: "Congratulations!!!", preferredStyle: .alert)
        let buttonOK = UIAlertAction(title: "OK", style: UIAlertActionStyle.default, handler: nil)
        let playAgain = UIAlertAction(title: "Play Again!", style: .default, handler: { (action) in

            self.myT = Timer.scheduledTimer(timeInterval: 3, target: self, selector: #selector(ViewController.movePicker), userInfo: nil, repeats: true)
        })

        alert.addAction(buttonOK)
        alert.addAction(playAgain)

        present(alert, animated: true, completion: nil)



    }

}




 //MARK: - picker
func numberOfComponents(in pickerView: UIPickerView) -> Int {

    return 1

}

func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    return myArr.count
}

func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    return "\( myArr[row])"
}


}

希望对你有帮助