pickerView didSelectRow输入了错误的UITextField

Question

我正在尝试遵循以下solution在一个UIViewController上具有多个UIPickerViews。他们建议为我已经完成的每个UITextfield标签，并能够实现行数，行标题和组件数。但是，在实现did select行时，我遇到了一个绊脚石。当我选择UITextField时，它将突出显示另一个UITextfield。下面是我到目前为止的代码。     类DriverViewController：UIViewController {

var selectedTrack: String?

var firstDriver: String?

var secondDriver: String?

var thirdDriver: String?
let  tracks = ["Melbourne", "Manama", "Shanghai", "Baku",
               "Barcelona", "Monaco", "Montreal","Le Castellet","Spielberg",
               "Silverstone","Hockenheim","Budapest","Francorchamps","Monza","Singapore","Sochi","Suzuka","Austin","Interlagos","Abu Dhabi"]
let drivers = ["Lewis Hamilton","Antonio Giovinazzi","Kimi Raikkonen","Charles Leclerc","Sebastian Vettel","Romain Grosjean","Kevin Magnussen","Lando Norris",
               "Carlos Sainz","Valtteri Bottas","Sergio Perez","Lance Stroll","Pierre Gasly","Max Verstappen","Nico Hulkenberg","Daniel Ricciardo","Alexander Albon","Daniil Kvyat","Robert Kubica","George Russell"]
@IBOutlet weak var TrackTextField: UITextField!


@IBOutlet weak var firstTextField: UITextField!

@IBOutlet weak var secondTextField: UITextField!


@IBOutlet weak var thirdTextField: UITextField!


override func viewDidLoad() {
    super.viewDidLoad()


    createTrackPicker()
    createDriverPicker()
    createToolBar()
    // Do any additional setup after loading the view.
}

func createTrackPicker() {
    let trackPicker = UIPickerView()
    trackPicker.tag = 0
    trackPicker.delegate = self
    TrackTextField.inputView = trackPicker
}

func createDriverPicker() {
    let driverPicker = UIPickerView()
    driverPicker.tag = 1
    driverPicker.tag = 2
    driverPicker.tag = 3
    driverPicker.delegate = self
    firstTextField.inputView = driverPicker
    secondTextField.inputView = driverPicker
    thirdTextField.inputView = driverPicker
}

func createToolBar() {

    let toolBar = UIToolbar()
    toolBar.sizeToFit()
    let doneButton = UIBarButtonItem(title: "Done", style: .plain, target: self, action: #selector(ViewController.dismissKeyboard))
    toolBar.setItems([doneButton], animated: false)
    toolBar.isUserInteractionEnabled = true
    TrackTextField.inputAccessoryView = toolBar
    firstTextField.inputAccessoryView = toolBar
    secondTextField.inputAccessoryView = toolBar
    thirdTextField.inputAccessoryView = toolBar

}
@objc func dismissKeyboard() {
    view.endEditing(true)
}
/*
// MARK: - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    // Get the new view controller using segue.destination.
    // Pass the selected object to the new view controller.
}
 */

}

 extension DriverViewController: UIPickerViewDelegate, UIPickerViewDataSource {
 func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    if pickerView.tag == 0 {
        return tracks.count
    } else {
        return drivers.count
    }
}


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

func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    if pickerView.tag == 0 {
        return "\(tracks[row])"
    } else {
        return "\(drivers[row])"
    }
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    if pickerView.tag == 0 {
        selectedTrack = tracks[row]
        TrackTextField.text = selectedTrack
    } else if pickerView.tag == 1 {
        firstDriver = drivers[row]
        firstTextField.text = firstDriver
    } else if pickerView.tag == 2 {
        secondDriver = drivers[row]
        secondTextField.text = secondDriver
    } else if pickerView.tag == 3 {
        thirdDriver = drivers[row]
        thirdTextField.text = thirdDriver
    }
  }
}

这是它在屏幕上的外观。

Answer 1

查看您的功能：

func createDriverPicker() {
    let driverPicker = UIPickerView()
    driverPicker.tag = 1
    driverPicker.tag = 2
    driverPicker.tag = 3
    driverPicker.delegate = self
    firstTextField.inputView = driverPicker
    secondTextField.inputView = driverPicker
    thirdTextField.inputView = driverPicker
}

请考虑一下在运行此代码后tag属性具有什么值。请记住，它只能有一个值。

您或者每次文本字段开始编辑时都需要更新选择器视图的tag属性，或者您应该放弃使用标记，而只需检查当前哪个文本字段是第一响应者。有关如何完成此操作的示例，请参见UIPickerView for each text field with different arrays (Swift/Firebase)。