swift - Xcode 8/swift 3 : Simple UIPicker code not working

Question

我有协议(protocol):

class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {

我有数据:

let muteForPickerData = ["minute(s)","hour(s)"]

在 viewDidLoad 我有:

muteForPicker.delegate = self
muteForPicker.dataSource = self

然后我有需要的方法:

func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
            return 1
        }

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

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

func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    }

我还是明白了

type viewcontroller does not conform to protocol UIPickerViewDataSource

Answer 1

UIPickerViewDataSource 方法 numberOfComponentsInPickerView 在 Swift 3 中已更改，这就是您收到此错误的原因。

func numberOfComponents(in pickerView: UIPickerView) -> Int {
    return 1
}

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

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

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {

}

有关更多详细信息，请阅读 Apple Documentation在 UIPickerView 上。

注意:您还需要添加 _ 作为第一个参数标签，就像 UIPickerViewDelegate 方法中的其他方法一样 titleForRow 和 didSelectRow。