swift - PickerView ViewForRow 无法识别组件

Question

我正在使用多个组件来制作计时器。当我将 pickerView 与 ViewForRow 合并时，我的 pickerView 无法识别我的第二个数据源

let hourDataSource = ["0", "1", "2", "3", "4", "5"]
let minDataSource = ["0", "10", "20", "30", "40", "50"]

func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView {
    let label = UILabel()

    if component == 0 {
        label.text = String(row)
        label.textAlignment = .center
    } else if component == 1 {
        label.text = String(row)
        label.textAlignment = .center
    }
    print(component)
    return label

}

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {

    if let label = pickerView.view(forRow: row, forComponent: component) as? UILabel {

        if component == 0, row > 1 {
            label.text = String(row) + " hours"
        } else if component == 0 {
            label.text = String(row) + " hour"
        } else if component == 1 {
            label.text = String(row) + " min"
        }
    }

    //print(component)
    let hour = dataSource[pickerView.selectedRow(inComponent: 0)]
    let min = minDataSource[pickerView.selectedRow(inComponent: 1)]
    timerPickerViewLbl.text = "\(hour):\(min) hrs"
}
 func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {

    if component == 0 {
        return dataSource[row]
    } else {
        return minDataSource[row]
    }
}

我正在打印组件，所以我知道它被调用了。当我删除 viewForRow 函数时，我的数据对于第一列和第二列是正确的。但是我丢失了数据旁边的小时和分钟标签。但是添加它会使我的第二列返回与第一列相同的数据。我错过了什么？

Answer 1

这就是您所需要的。您应该只使用其中一个委托(delegate)，titleForRow 或 viewForRow 因为它们都做同样的事情，即给行赋予标题。您的问题出在您实际返回数据的 didSelect 委托(delegate)中。

let hourDataSource = ["0", "1", "2", "3", "4", "5"]
let minDataSource = ["0", "10", "20", "30", "40", "50"]

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    let hour = dataSource[pickerView.selectedRow(inComponent: 0)]
    let min = minDataSource[pickerView.selectedRow(inComponent: 1)]
    timerPickerViewLbl.text = "\(hour):\(min) hrs"
}

func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    if component == 0, row > 1 {
        return "\(hourDataSource[row]) hours"
    } else if component == 0 {
        return "\(hourDataSource[row]) hour"
    } else if component == 1 {
        return "\(minDataSource[row]) mins"
    }
    return nil
}