Swift中的多个pickerview didSelectRow错误

Posted 2023-02-24

【中文标题】Swift中的多个pickerview didSelectRow错误

【英文标题】：multiple pickerview didSelectRow error in Swift

【发布时间】：2020-04-23 19:19:37

【问题描述】：

我有 2 个选择器视图，1 个选择器视图用于从数组中选择一种加密货币，另一个选择器视图用于从数组中选择一种货币。我遇到的问题是，当我在模拟器上运行应用程序并在 cryptoPicker 中选择加密货币时，该应用程序还会从 currencyPicker 中选择相同的数组值，反之亦然。除非用户选择，否则我不希望从两个数组中提取 0 的数组值。

@IBOutlet weak var cryptoCurrentRate: UILabel!
@IBOutlet weak var currencyLabel: UILabel!
@IBOutlet weak var currencyPicker: UIPickerView!
@IBOutlet weak var cryptoPicker: UIPickerView!
@IBOutlet weak var cryptoLabel: UILabel!


var coinManager = CoinManager()


override func viewDidLoad() 
    super.viewDidLoad()
    // Do any additional setup after loading the view.
    coinManager.delegate = self
    currencyPicker.dataSource = self
    currencyPicker.delegate = self
    cryptoPicker.dataSource = self
    cryptoPicker.delegate = self   

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


    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int 
        if pickerView == currencyPicker 
        return coinManager.currencyArray.count
        
        if pickerView == cryptoPicker 
        return coinManager.cryptoArray.count
    
        return 0
    
    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? 
        if pickerView == currencyPicker 
        return coinManager.currencyArray[row]
        
        if pickerView == cryptoPicker 
        return coinManager.cryptoArray[row]
    
        return ""
    

    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) 
        let selectedCurrency = coinManager.currencyArray[row]
        let selectedCrypto = coinManager.cryptoArray[row]
        coinManager.fetchCryptoCoin(assetIdBase: selectedCrypto, assetIdQuote: selectedCurrency)
    

【参考方案1】：

对picker和'didSelectRow'做同样的检查，你可以这样做：

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) 
     var selectedCurrency: CurrencyModel? = nil
     var selectedCrypt: CryptModel? = nil


    if pickerView == currencyPicker 
        selectedCurrency = coinManager.currencyArray[row]
    
    if pickerView == cryptoPicker 
        selectedCrypto = coinManager.cryptoArray[row]
    

    coinManager.fetchCryptoCoin(assetIdBase: selectedCrypt == nil ? coinManager.cryptoArray[.zero] : selectedCrypt!, assetIdQuote: selectedCurrency == nil ? coinManager.currencyArray[.zero] : selectedCurrency!)

默认情况下，它会从 'coinManager.currencyArray' 或 'coinManager.cryptoArray' 中获取第一个值

【讨论】：

抱歉回复晚了，我试过了，但最终还是出现了在每个选择器上显示同一行的错误。因此，如果在选择器 1 上选择了第 1 行，那么它也在选择器 2 上被选择。我最终只是将 selectedCurrency 和 selectedCrypt 都放在了 1 个选择器（同一个选择器）上，因为这种方法更容易实现我的目标。但我想知道如何为可能的未来项目做到这一点。