ios - 使用选取器 View 时出现索引超出范围错误

我使用不同的数组填充了一个选择器 View ，具体取决于您单击的文本字段。但是，每当我选择“Untergrund”数组的第五行时，应用程序就会崩溃，并出现索引超出范围错误。它向我显示行 int = 4 和组件 int = 0。错误发生在在 did select 行函数中设置第一个 if 语句的行中。我不知道为什么会这样......

以下是相关代码:

@IBOutlet weak var Stadt: UITextField!
@IBOutlet weak var Strasse: UITextField!
@IBOutlet weak var Platzart: UITextField!
@IBOutlet weak var Groesse: UITextField!
@IBOutlet weak var AnzToreKoerbe: UITextField!
@IBOutlet weak var Untergrund: UITextField!

// Variable für die Firebase Database

override func viewDidLoad() {
    super.viewDidLoad()

    Stadt.delegate = self
    Untergrund.delegate = self
    Groesse.delegate = self
    AnzToreKoerbe.delegate = self
    Platzart.delegate = self
    Picker.delegate = self
}

@IBOutlet weak var Picker: UIPickerView!

var currentData = [""]

let UntergrundArray = ["Asphalt", "Kunstrasen Sand", "Kunstrasen Granulat", "Rasen", "Tartan", " "]
let StadtArray = ["Norderstedt", "Hamburg", "Berlin", "München"]
let GroesseArray = [ "2 vs 2", "3 vs 3", "4 vs 4", "5 vs 5"]
let AnzTorKoerbe = ["1", "2", "3", "4"]
let Art = ["Fußball", "Basketball"]

func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool{
    if textField.tag == 1{
        currentData = StadtArray
    }else if textField.tag == 2{
        currentData = UntergrundArray
    }else if textField.tag == 3 {
        currentData = GroesseArray
    }else if textField.tag == 4 {
        currentData = AnzTorKoerbe
    }else if textField.tag == 5 {
        currentData = Art

    }

    Picker.reloadAllComponents()

    return false;
}

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

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

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

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    let itemSelected = currentData[row]

    print(itemSelected)

    if (itemSelected == StadtArray[row]) {
        Stadt.text = StadtArray[row]
    }else if (itemSelected == UntergrundArray[row]) {
        Untergrund.text = UntergrundArray[row]
    }else if (itemSelected == GroesseArray[row]) {
        Groesse.text = GroesseArray[row]
    }else if (itemSelected == AnzTorKoerbe[row]) {
        AnzToreKoerbe.text = AnzTorKoerbe[row]
    }else {
        Platzart.text = Art[row]
    }
}

---

Best Answer-推荐答案

currentData 可以是任何其他数组。 row 可以用于比某些数组更大的索引。这就是崩溃的原因。

正确的解决方案是修正您确定要更新哪个标签的方式。

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    let itemSelected = currentData[row]

    if currentData === StadtArray {
        Stadt.text = itemSelected
    } else if currentData === UntergrundArray {
        Untergrund.text = itemSelected
    } else ... and the others as needed
}

虽然更好的选择可能是添加另一个属性来跟踪当前文本字段。

var currentField: UITextField?

然后更新textFieldShouldBeginEditing:

func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool{
    currentField = textField
    if textField.tag == 1 {
        currentData = StadtArray
    } else if textField.tag == 2 {
        currentData = UntergrundArray
    } else if textField.tag == 3 {
        currentData = GroesseArray
    } else if textField.tag == 4 {
        currentData = AnzTorKoerbe
    } else if textField.tag == 5 {
        currentData = Art
    }

    Picker.reloadAllComponents()

    return false;
}

然后更新didSelectRow:

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    let itemSelected = currentData[row]

    if let currentField = currentField {
        currentField.text = itemSelected
    }
}

关于ios - 使用选取器 View 时出现索引超出范围错误，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/42655580/