Ios Xcode NSException和NSUnknownKeyException

我不熟悉MacOS和Xcode，以前从未使用过它们

我必须使用Xcode为我的班级制作一个简单的游戏。我成功地设置了一切（使用VirtualBox），观看了一些教程并制作了一个简单的石头、布、剪刀游戏

建筑是成功的，但当模拟器启动我的应用程序时，我的三个按钮（Paper_按钮）中的一个出现错误。即使我在ViewController中注释按钮的代码，我仍然会得到错误。我查了我的代码，但什么都没有。。。我很抱歉这个愚蠢的问题，但我似乎没有找到任何解决办法

这就是错误：

Exception   NSException *   "[<RPS.ViewController 0x7fdf76008840> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key PAPER_Button."   0x0000600001ab83f0
name    __NSCFConstantString *  "NSUnknownKeyException" 0x00007fff801e80a0
reason  __NSCFString *  "[<RPS.ViewController 0x7fdf76008840> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key PAPER_Button."   0x00006000025e8280
userInfo    __NSDictionaryI *   2 key/value pairs   0x00006000001a10c0
reserved    __NSDictionaryM *   2 key/value pairs   0x00006000014c5fc0

libc++abi.dylib:以NSException类型的未捕获异常终止
***由于未捕获的异常“NSUnknownKeyException”而终止应用程序，原因：“[setValue:forUndefinedKey:]：此类不符合密钥纸张按钮的键值编码。”
以NSException类型的未捕获异常终止
CoreSimulator 732.18.6-设备：iPhone 11（BCA23623-0F8A-46DA-BE7F-F3B81149500E）-运行时：iOS 14.4（18D46）-设备类型：iPhone 11
***由于未捕获的异常“NSUnknownKeyException”而终止应用程序，原因：“[setValue:forUndefinedKey:]：此类不符合密钥纸张按钮的键值编码。”
以NSException类型的未捕获异常终止
CoreSimulator 732.18.6-设备：iPhone 11（BCA23623-0F8A-46DA-BE7F-F3B81149500E）-运行时：iOS 14.4（18D46）-设备类型：iPhone 11
（lldb）

错误显示，.xib或.storyboard文件引用的

纸张按钮在您的
ViewController
类中不存在

我想从.xib或.storyboard文件中删除
PAPER\u按钮将修复错误。
转到Interface Builder，检查iAction是否正确连接。顺便说一下，根据命名约定，函数名应该是小写的。您有一个名为
PAPER_Button
的变量，它是您在代码中创建的，在脚本中创建的，并在两者之间建立了连接。但您后来在代码中删除了它，但没有删除连接。这就是它失败的原因。对于其余部分，命名也很重要，因此强烈建议使用
lowerCamelCase
。

    //
//  ViewController.swift
//  RPS
//
//  Created by MaiorCristian on 4/21/21.
//

import UIKit

//@interface
//SettingsViewController:
//UITableViewController

//BEFORE: UIViewController
//AFTER: UITableViewController

class ViewController: UIViewController {
    
    var player_points = 0
    var cpu_points = 0
    
    @IBOutlet weak var CPU_label: UILabel!
    @IBOutlet weak var YOU_label: UILabel!
    @IBOutlet weak var CPU_Image: UIImageView!
    @IBOutlet weak var WINNER: UILabel!
    
    
    var playersChoice = 0;
    @IBAction func ROCK_Button(_ sender: Any) {
        playersChoice = 1
        let cpuNumberChoice = Int.random(in: 1...3)
        setCPUimage(imageView: CPU_Image, imageNumber: cpuNumberChoice)
        
        //rock 1, paper 2, scissors 3
        
        //rock - rock
        if cpuNumberChoice == 1 && playersChoice == 1 {
            //tie
            WINNER.text = "WINNER: TIE!"
        }
        //paper - rock
        if cpuNumberChoice == 2 && playersChoice == 1 {
            cpu_points = cpu_points + 1
            WINNER.text = "WINNER: CPU!"        }
        //scissors - rock
        if cpuNumberChoice == 3 && playersChoice == 1 {
            player_points = player_points + 1
            WINNER.text = "WINNER: YOU!"        }
        
        YOU_label.text = "YOU: \(player_points)"
        CPU_label.text = "CPU: \(cpu_points)"
        
    }
    
    /*@IBAction func PAPER_Button(_ sender: Any) {
        playersChoice = 2
        let cpuNumberChoice = Int.random(in: 1...3)
        setCPUimage(imageView: CPU_Image, imageNumber: cpuNumberChoice)
        
        //rock 1, paper 2, scissors 3
        
        //paper - paper
        if cpuNumberChoice == 2 && playersChoice == 2 {
            WINNER.text = "WINNER: TIE!"        }
        //scissors - papper
        if cpuNumberChoice == 3 && playersChoice == 2 {
            cpu_points = cpu_points + 1
            WINNER.text = "WINNER: CPU!"        }
        //rock - papper
        if cpuNumberChoice == 1 && playersChoice == 2 {
            player_points = player_points + 1
            WINNER.text = "WINNER: YOU!"        }
        
        YOU_label.text = "YOU: \(player_points)"
        CPU_label.text = "CPU: \(cpu_points)"
        
    }
    */
    @IBAction func SCISSORS_Button(_ sender: Any) {
        playersChoice = 3
        let cpuNumberChoice = Int.random(in: 1...3)
        setCPUimage(imageView: CPU_Image, imageNumber: cpuNumberChoice)
        
        //rock 1, paper 2, scissors 3
        
        //scissors - scissors
        if cpuNumberChoice == 3 && playersChoice == 3 {
            WINNER.text = "WINNER: TIE!"        }
        //rock - scissors
        if cpuNumberChoice == 1 && playersChoice == 3 {
            cpu_points = cpu_points + 1
            WINNER.text = "WINNER: CPU!"        }
        //paper - scissors
        if cpuNumberChoice == 2 && playersChoice == 3 {
            player_points = player_points + 1
            WINNER.text = "WINNER: YOU!"        }
        
        YOU_label.text = "YOU: \(player_points)"
        CPU_label.text = "CPU: \(cpu_points)"
        
    }
    ///

        //
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
    }

    //@IBAction func

    func setCPUimage(imageView:UIImageView, imageNumber: Int){
        switch imageNumber {
        case 1://rock
            imageView.image = UIImage(named: "IMG_20210421_121204_edit_267680766477383")
        case 3://scissors
            imageView.image = UIImage(named: "IMG_20210421_121232_edit_267656474039366")
        case 2://paper
            imageView.image = UIImage(named: "IMG_20210421_121216_edit_267673424825822")
        
        default:
            print("error")
            //imageView.image = UIImage(named: "rock")
        }
        
    }
    
    
    
    
}



    libc++abi.dylib: terminating with uncaught exception of type NSException
*** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<RPS.ViewController 0x7fdf76008840> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key PAPER_Button.'
terminating with uncaught exception of type NSException
CoreSimulator 732.18.6 - Device: iPhone 11 (BCA23623-0F8A-46DA-BE7F-F3B81149500E) - Runtime: iOS 14.4 (18D46) - DeviceType: iPhone 11
*** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<RPS.ViewController 0x7fdf76008840> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key PAPER_Button.'
terminating with uncaught exception of type NSException
CoreSimulator 732.18.6 - Device: iPhone 11 (BCA23623-0F8A-46DA-BE7F-F3B81149500E) - Runtime: iOS 14.4 (18D46) - DeviceType: iPhone 11
(lldb)