如何从pickView获取具有多个组件的确切值

Question

我有一个PickerView和这样的标签：

我想，当我更改组件中每一行的值时，它会将值分配给上面的标签。

例如：当我在第一个组件中选择“Blue”而在第二个组件中选择“Two”时，它会将“Blue Two”分配给Label。

我尝试过这样，但是效果不好，当我在第二个组件中选择第六个值时会崩溃：

import UIKit

class ViewController: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate {

    @IBOutlet var colorLabel: UILabel!
    let colors = ["Red", "Green", "Blue", "Black", "White"]
    let numbers = ["One", "Two", "Three", "Four" ,"Five", "Six", "Seven"]
    var array = [[String]]()

    override func viewDidLoad() {
        super.viewDidLoad()
        array = [colors, numbers]
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }

    func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
        return array.count
    }

    func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return array[component].count
    }

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

    func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        colorLabel.text = component == 0 ? array[component][row] + " " + array[component][row] : array[component][row] + " " + array[component][row]
    }

}

Answer 1

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

    var selectedValueFirstRow = pickerView.selectedRowInComponent(0)
    var selectedValueSecondRow = pickerView.selectedRowInComponent(1)

    colorLabel.text = colors[selectedValueFirstRow] + " " + numbers[selectedValueSecondRow]
}

您的代码崩溃了，因为它超出了第一个数组的索引

Answer 2

我在ViewController

的顶部添加这些行

var colorString = ""
var numberString = ""

并更改didSelectRow函数，如下所示：

 func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        if component == 0 {
            colorString = array[component][row]
        } else {
            numberString = array[component][row]
        }
        resultLabel.text = colorString + " " + numberString
    }

现在效果很好。