Question

当我点击textField时，将出现输入区域，但只有1行，其中包含空白内容。（我希望3行：a，b和c）

我将numberOfRowsInComponent和titleForRow函数中的返回值更改为常量，但是得到了相同的结果（1个空白行）。也许这两个函数永远不会被调用。

请帮助我！

//In ViewDidLoad Function (ViewController.swift):
let myPickerView: MyPickerView = MyPickerView(arrData: ["a","b","c"]){ selected in
     print(selected)
}

textField.inputView = myPickerView.picker





//In MyPickerView.swift
class MyPickerView: NSObject, UIPickerViewDelegate, UIPickerViewDataSource {

    var arrData: Array<String>
    var picker: UIPickerView
    var action: (_ selected: String) -> Void

    public init(
        arrData: Array<String>,
        action: @escaping (_ selected: String) -> Void
        ) {

        self.arrData = arrData
        self.action = action
        self.picker = UIPickerView()

        super.init()

        self.picker.delegate = self
        self.picker.dataSource = self    
    }

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

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

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

    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        self.action(self.arrData[row])
    }
}

Answer 1

我发现了问题。当我将myPickerView更改为全局变量（放在ViewDidLoad之外）时，一切都很好。

var myPickerView: MyPickerView?

//In ViewDidload
myPickerView = MyPickerView(arrData: ["a","b","c"]){ selected in
     print(selected)
}

PickerView在文本字段输入中不显示任何内容

1 个答案: