ios - 未调用 UIPickerView didSelectRow

Question

(Swift、Xcode6、iOS8、iPhone)

在我的 UIPickerView 控件中，didSelectRow 没有被调用。

• 是的，我已将 Splash 设置为选择器的委托(delegate)(和数据源)。
• Splash 扩展了 UIViewController 类
• 所有其他功能都正常工作。没有错误，选择器旋转，有五行，并显示其他函数中定义的行号。

didSelectRow 方法何时被调用？我是否需要实现某种Done 按钮，或者当用户停止旋转时会触发此方法吗？我需要实现单独的通知吗？ tyvm:)

class Splash: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate {

@IBOutlet var countryPicker : UIPickerView = nil

func numberOfComponentsInPickerView(pickerView: UIPickerView!) -> Int {
    return 1
}
func pickerView(pickerView: UIPickerView!, numberOfRowsInComponent component: Int) -> Int {
    return 5
}
func pickerView(pickerView: UIPickerView!, titleForRow row: Int, forComponent component: Int) -> String {
    return "\(row)"

}
func pickerView(pickerView: UIPickerView!, didSelectRow row: Int, forComponent component: Int) -> Int {
    println("Row: \(row)")
    return row
}
override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}
}

Answer 1

您的签名有误，pickerView:didSelectRow:forComponent: 返回 void，而不是整数。尝试:

func pickerView(pickerView: UIPickerView!, didSelectRow row: Int, forComponent component: Int) {
    println("Row: \(row)")
}