Question

我正在尝试在两个不同的文本框上使用两个pickerviews（我将它们在文本框下方对齐并隐藏直到被调用）。我将隐藏pickerviews，直到准备使用并将两个文本框都绑定到它们对应的文本框。第一个pickerview工作正常，但是当我单击第二个pickerview时，我的列表没有出现，并且仍然隐藏。我已多次阅读代码，但找不到问题，并且观看了多个视频并检查了苹果文档，但无济于事。下面发布了代码以供查看和帮助。预先感谢！

class fifthViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource, UITextFieldDelegate {

    @IBOutlet weak var heightInput: UITextField!
    @IBOutlet weak var weightInput: UITextField!
    @IBOutlet weak var bmiOutput: UITextField!
    @IBOutlet weak var weightPicker: UIPickerView!
    @IBOutlet weak var heightPicker: UIPickerView!

    var height = ["48", "49", "50"]
    var weight = ["90", "91", "92"]

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

    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        var countrows : Int = height.count
        if pickerView == weightPicker {
        countrows = self.weight.count
        }
        return countrows
    }

    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        if pickerView == heightPicker {
        let titleRow = height[row]
            return titleRow
        }
        else if pickerView == weightPicker {
            let titleRow = weight[row]
            return titleRow
        }
        return ""
    }

    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        if pickerView == heightPicker {
            self.heightInput.text = self.height[row]
            self.heightPicker.isHidden = true
        }
        else if pickerView == weightPicker {
            self.weightInput.text = self.weight[row]
            self.weightPicker.isHidden = true
        }
    }

    func textFieldDidBeginEditing(_ textField: UITextField) {
        if (textField == self.heightInput) {
            self.heightPicker.isHidden = false
        }
        else if (textField == self.weightInput) {
            self.weightInput.isHidden = false
        }
    }```

Answer 1

在textFieldDidBeginEditing()中，您需要将self.weightPicker.isHidden设置为false而不是self.weightInput.isHidden。

func textFieldDidBeginEditing(_ textField: UITextField) {
    if (textField == self.heightInput) {
        self.heightPicker.isHidden = false
    }
    else if (textField == self.weightInput) {
        self.weightPicker.isHidden = false
    }
}

修改您的代码以使用inputView s

我同意@ PaulW11的评论：

“如果您做出选择器视图，您几乎可以肯定会过得更好每个文本字段的inputView。”

这是基本设置所需的更改。摆脱情节提要中的选择器，并断开@IBOutlet连接。

然后添加以下修改：

// These are no longer outlets since they're created in code
var weightPicker: UIPickerView!
var heightPicker: UIPickerView!

override func viewDidLoad() {
    super.viewDidLoad()

    // set up the picker views
    self.weightPicker = UIPickerView()
    self.weightPicker.delegate = self
    self.weightPicker.dataSource = self

    self.heightPicker = UIPickerView()
    self.heightPicker.delegate = self
    self.heightPicker.dataSource = self

    self.heightInput.inputView = self.heightPicker
    self.weightInput.inputView = self.weightPicker
}

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    if pickerView == heightPicker {
        self.heightInput.text = self.height[row]

        // make picker go away after value has been selected
        self.heightInput.resignFirstResponder()
    }
    else if pickerView == weightPicker {
        self.weightInput.text = self.weight[row]

        // make picker go away after value has been selected
        self.weightInput.resignFirstResponder()
    }
}

使用两个UIPickerViews的问题-第一个起作用，第二个不起作用

1 个答案: