Question

我是Swift和Xcode的新手，我想为在SegmentedControl中选择Segment的关系将行设置为PickerView。我尝试了以下操作，将数组firstInputUnitChooseData设置为PickerView firstInputUnitChoose的行：

class FirstViewController: UITableViewController, UIPickerViewDelegate, UIPickerViewDataSource {

    @IBOutlet weak var wantedInputProperty: UISegmentedControl!
    @IBOutlet weak var firstInputUnitChoose: UIPickerView!

    var wantedInputPropertyData: [String] = [String]()
    var firstInputUnitChooseData: [String] = [String]()

    override func viewDidLoad() {
        super.viewDidLoad()

        // Connect data
        self.firstInputUnitChoose.delegate = self
        self.firstInputUnitChoose.dataSource = self

        wantedInputProperty.addTarget(self, action: #selector(FirstViewController.doSomething), for: .valueChanged)

    }

    @IBAction func doSomething() {
        let choosableFirstUnit = wantedInputProperty.titleForSegment(at: wantedInputProperty.selectedSegmentIndex)
        switch choosableFirstUnit {
        case "p", "p,h", "p,s", "p,t", "p,x", "p,\u{03C1}":
            firstInputUnitChooseData = ["Bar", "MPa", "Pa"]
        case "t", "t,x" :
            firstInputUnitChooseData = ["°C", "K"]
        case "h,s", "h,\u{03C1}":
            firstInputUnitChooseData = ["J/Kg", "kJ/Kg"]
        default:
            firstInputUnitChooseData = ["X"]
        }
    }

    // The number of columns of data
    func numberOfComponents(in pickerView: UIPickerView) -> Int {

        return 1
    }

    // Number of rows of data
    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {

        return firstInputUnitChooseData.count
    }

    // The data to return for the row and component (column) that's being passed in
    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {

        return firstInputUnitChooseData[row]
    }

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

        // Create action for selected PickerView row
    }

如果我在print(chooseableFirstUnit)中使用print(firstInputUnitChooseData)或func DoSomething()，它将在控制台中输出正确的数据。

例如：如果设置了数组

firstInputUnitChooseData = [“ Bar”，“ MPa”，“ Pa”]

直接在func viewDidLoad()内部，它可以工作，但这不是我想要的。

Answer 1

您需要重新加载pickerView，因此在函数doSomething的末尾要做

self.firstInputUnitChoose.reloadAllComponents()

在SegmentedControl上执行操作后如何在PickerView中设置行

1 个答案: