线程1：exc_bad_instruction（code = exc_i386_invop，subcode = 0x0）/致命错误：索引超出范围

Question

我正在尝试开发一个应用程序，现在我想通过2个不同的UIPickerViews的输入来编辑标签的文本。

起初我会收到错误。
"thread 1: exc_bad_instruction(code=exc_i386_invop,subcode=0x0)" 指着一些代码（见代码），但现在我只得到错误 "fatal error: Index out of range"

问题在于第一个选择器，如果我在那里更改任何东西（在模拟器中！），应用程序崩溃了。如果我仅更改第二个选择器然后更新标签，则更改为“1天”或“2周”，而不是仅仅“天”或“周”。

我的故事板：

我的代码：

import UIKit

class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {

@IBOutlet weak var PickerView1: UIPickerView!
@IBOutlet weak var PickerView2: UIPickerView!
@IBOutlet weak var outputLabel: UILabel!
@IBAction func changeLabel(_ sender: UIButton) {
    outputLabel.text = outputTotal
}

var list1 = [""]
var list2 = [""]
var output1 = ""
var output2 = ""
var outputTotal = ""

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

// Aangeven welke items er in de pickerview komen
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    if (pickerView.tag == 1){
        return "\(list1[row])"
    } else {
        return "\(list2[row])"
    }
}

// Aantal rijen weergeven
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    if (pickerView.tag == 1){
        return list1.count
    } else {
        return list2.count
    }
}

// Label veranderen naar input van PickerView1
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    output1 = list1[row]
    output2 = list2[row] // error points here
    outputTotal = output1 + " " + output2
}

override func viewDidLoad() {
    list1 = ["1", "2", "3", "4", "5", "6", "7", "8"]
    list2 = ["days", "weeks"]
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}
}

如果有人可以帮助我，谢谢你！

Answer 1

我想你忘了检测pickView中选择的pickerView(_:didSelectRow:inComponent:)：

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    if pickerView.tag == 1 {
        output1 = list1[row]
    } else {
        output2 = list2[row]
    }
    outputTotal = output1 + " " + output2
}