Question

我是一名高中生，为学校项目创建一个简单的应用程序。这是我第一次使用Swift语言和使用Xcode创建应用程序。每次我运行应用程序时，它会在打开之前崩溃。这是崩溃后显示的内容：

Error Message

这是代码：

import UIKit
import Foundation

class ViewController: UIViewController {

    @IBOutlet weak var coffeeOutput: UILabel!
    @IBOutlet weak var check1: UILabel!
    let things = UserDefaults.standard

    var coffeeShops = [0,0,0,0,0,0,0,0,0]

    // 0 days: Int = 0
    // 1 highland: Int = 0
    // 2 starbucks: Int = 0
    // 3 heine: Int = 0
    // 4 quills: Int = 0
    // 5 bean: Int = 0
    // 6 sunergos: Int = 0
    // 7 press: Int = 0
    // 8 please: Int = 0



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

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

    @IBAction func highlands(sender: UIButton) {
        things.set(things.integer(forKey: "highland")+1, forKey: "highland" )
        things.set(things.integer(forKey: "days")+1, forKey: "days" )
        things.synchronize()
   }

    @IBAction func downtown(_:AnyObject) {

        things.set(things.integer(forKey: "please")+1, forKey: "please" )
        things.set(things.integer(forKey: "starbucks")+1, forKey: "starbucks" )
        things.set(things.integer(forKey: "press")+1, forKey: "press" )
        things.synchronize()
    }

    @IBAction func germantown(_:AnyObject) {
        things.set(things.integer(forKey: "heine")+1, forKey: "heine" )
        things.set(things.integer(forKey: "bean")+1, forKey: "bean" )
        things.set(things.integer(forKey: "sunergos")+1, forKey: "sunergos" )
        things.synchronize()
    }

    @IBAction func school(_:AnyObject) {
        things.set(things.integer(forKey: "quills")+1, forKey: "quills" )
        things.synchronize()
    }

    @IBAction func homework(_:AnyObject) {

        things.set(things.integer(forKey: "days")+1, forKey: "days" )
        things.set(things.integer(forKey: "starbucks")+1, forKey: "starbucks" )
        things.set(things.integer(forKey: "heine")+1, forKey: "heine" )
        things.set(things.integer(forKey: "quills")+1, forKey: "quills" )
        things.set(things.integer(forKey: "sunergos")+1, forKey: "sunergos" )
        things.synchronize()
    }

    @IBAction func meeting(_:AnyObject) {

        things.set(things.integer(forKey: "days")+1, forKey: "days" )
        things.set(things.integer(forKey: "starbucks")+1, forKey: "starbucks" )
        things.set(things.integer(forKey: "heine")+1, forKey: "heine" )
        things.set(things.integer(forKey: "quills")+1, forKey: "quills" )
        things.set(things.integer(forKey: "bean")+1, forKey: "bean" )
        things.set(things.integer(forKey: "press")+1, forKey: "press" )
        things.synchronize()
    }

    @IBAction func toGo(_:AnyObject) {

        things.set(things.integer(forKey: "starbucks")+1, forKey: "starbucks" )
        things.set(things.integer(forKey: "heine")+1, forKey: "heine" )
        things.set(things.integer(forKey: "bean")+1, forKey: "bean" )
        things.set(things.integer(forKey: "sunergos")+1, forKey: "sunergos" )
        things.set(things.integer(forKey: "please")+1, forKey: "please" )
        things.synchronize()
    }

    @IBAction func hang(_:AnyObject) {

        things.set(things.integer(forKey: "highland")+1, forKey: "highland" )
        things.set(things.integer(forKey: "days")+1, forKey: "days" )
        things.set(things.integer(forKey: "heine")+1, forKey: "heine" )
        things.synchronize()

    }

    @IBAction func morning(_:AnyObject) {

        things.set(things.integer(forKey: "days")+1, forKey: "days" )
        things.set(things.integer(forKey: "starbucks")+1, forKey: "starbucks" )
        things.set(things.integer(forKey: "heine")+1, forKey: "heine" )
        things.set(things.integer(forKey: "bean")+1, forKey: "bean" )
        things.set(things.integer(forKey: "sunergos")+1, forKey: "sunergos" )
        things.set(things.integer(forKey: "press")+1, forKey: "press" )
        things.synchronize()
    }

    @IBAction func midday(_:AnyObject) {
        //0 2 3 4 6 7 8
        things.set(things.integer(forKey: "days")+1, forKey: "days" )
        things.set(things.integer(forKey: "starbucks")+1, forKey: "starbucks" )
        things.set(things.integer(forKey: "heine")+1, forKey: "heine" )
        things.set(things.integer(forKey: "quills")+1, forKey: "quills" )
        things.set(things.integer(forKey: "sunergos")+1, forKey: "sunergos" )
        things.set(things.integer(forKey: "press")+1, forKey: "press" )
        things.set(things.integer(forKey: "please")+1, forKey: "please" )
        things.synchronize()
    }

    @IBAction func night(_:AnyObject) {
        things.set(things.integer(forKey: "days")+1, forKey: "days" )
        things.set(things.integer(forKey: "highland")+1, forKey: "highland" )
        things.set(things.integer(forKey: "heine")+1, forKey: "heine" )
        things.synchronize()
    }

    // 0 days: Int = 0
    // 1 highland: Int = 0
    // 2 starbucks: Int = 0
    // 3 heine: Int = 0
    // 4 quills: Int = 0
    // 5 bean: Int = 0
    // 6 sunergos: Int = 0
    // 7 press: Int = 0
    // 8 please: Int = 0

    @IBAction func computeShop(_:AnyObject) {
        var max = things.integer(forKey: "days")
        var maxKey = "days"
        for element in UserDefaults.standard.dictionaryRepresentation().keys.elements{
            if(things.integer(forKey: element)>max){
                max = things.integer(forKey: element)
                maxKey = element
            }
        }
        self.coffeeOutput.text = maxKey

        for element in UserDefaults.standard.dictionaryRepresentation().keys.elements{
            things.set(0,forKey: element)
            things.synchronize()
        }


    }
}

这是堆栈跟踪： {

2017-04-13 12：13：04.411按钮[95215：59212987] - [ NSCFNumber _getCString：maxLength：encoding：]：无法识别的选择器发送到实例0xb000000000000003 2017-04-13 12：13：04.574按钮[95215：59212987] ***由于未捕获的异常'NSInvalidArgumentException'终止应用程序，原因：' - [__ NSCFNumber _getCString：maxLength：encoding：]：无法识别的选择器发送到实例0xb000000000000003' ***第一次抛出调用堆栈：（ 0 CoreFoundation 0x000000010b4f4d4b __exceptionPreprocess + 171 1 libobjc.A.dylib 0x000000010af5621e objc_exception_throw + 48 2 CoreFoundation 0x000000010b564f04 - [NSObject（NSObject）doesNotRecognizeSelector：] + 132 3 CoreFoundation 0x000000010b47a005 ___ forwarding _ + 1013 4 CoreFoundation 0x000000010b479b88 _CF_forwarding_prep_0 + 120 5 CoreFoundation 0x000000010b42e89b CFStringGetCString + 171 6 CoreFoundation 0x000000010b43e77d CFLocaleCreateCanonicalLocaleIdentifierFromString + 77 7 CoreFoundation 0x000000010b43e327 _CFLocaleCopyCurrentGuts + 487 8 CoreFoundation 0x000000010b43e109 + [NSLocale currentLocale] + 9 9基金会0x000000010aa19376 - [NSUserDefaults（NSUserDefaults）init] + 1637 10基金会0x000000010aa18cb5 + [NSUserDefaults（NSUserDefaults）standardUserDefaults] + 81 11 UIKit 0x000000010b9438df ___UIApplicationMainPreparations_block_invoke_2 + 53 12 libdispatch.dylib 0x000000010eb7d978 _dispatch_call_block_and_release + 12 13 libdispatch.dylib 0x000000010eba70cd _dispatch_client_callout + 8 14 libdispatch.dylib 0x000000010eb8865f _dispatch_root_queue_drain + 1450 15 libdispatch.dylib 0x000000010eb88059 _dispatch_worker_thread3 + 123 16 libsystem_pthread.dylib 0x000000010ef56736 _pthread_wqthread + 1299 17 libsystem_pthread.dylib 0x000000010ef56211 start_wqthread + 13 ） libc ++ abi.dylib：以NSException类型的未捕获异常终止（LLDB） }

知道问题是什么吗？

Answer 1

检查xib文件的文件所有者
检查与视图控制器的连接（插座和操作）

修好后，清理构建（cmd + shift + k）并重新运行。

如果它仍然崩溃，在你的所有课程中放置断点并找出崩溃的确切位置。请给我们一些额外的信息，我们会尝试帮助更多

注意：不需要同步

Answer 2

在ViewDidLoad方法中提供断点。如果它在到达之前就崩溃了。然后只需检查storyBoard中的连接。您可能删除了一些连接，故事板可能仍在尝试找到它。

在Xcode中崩溃应用

2 个答案: