StopWatch应用程序不断崩溃

Question

因此，我通过网上找到的教程制作了一个简单的秒表应用程序。 我遵循了福特的代码字，并创建了一个UI来连接它。 但是，每当我尝试运行该程序时，iOS Simulator都无法通过显示应用程序名称的屏幕。 然后产生大量代码，并突出显示以下内容：

class AppDelegate: UIResponder, UIApplicationDelegate {`

在其下表示THREAD 1: signal SIGABRT

这意味着什么？

同样在控制台中，我得到以下消息：

（对大部分代码事先表示歉意，将其制表符似乎无效）

2015-06-15 15:53:54.313 stopwatch2[20524:1296474] ***   Terminating    app due to uncaught exception 'NSUnknownKeyException', reason:     '[<stopwatch2.ViewController 0x7f9280476960> setValue:forUndefinedKey:]:   this class is not key value coding-compliant for the key display.'
*** First throw call stack:
(
    0   CoreFoundation                      0x000000010fcecc65 __exceptionPreprocess + 165
    1   libobjc.A.dylib                     0x0000000111857bb7 objc_exception_throw + 45
    2   CoreFoundation                      0x000000010fcec8a9 -[NSException raise] + 9
    3   Foundation                          0x000000011010ab53 -[NSObject(NSKeyValueCoding) setValue:forKey:] + 259
    4   CoreFoundation                      0x000000010fc34d50 -[NSArray makeObjectsPerformSelector:] + 224
    5   UIKit                               0x000000011086352b -[UINib instantiateWithOwner:options:] + 1506
    6   UIKit                               0x00000001106bb718 -[UIViewController _loadViewFromNibNamed:bundle:] + 242
    7   UIKit                               0x00000001106bbd08 -[UIViewController loadView] + 109
    8   UIKit                               0x00000001106bbf79 -[UIViewController loadViewIfRequired] + 75
    9   UIKit                               0x00000001106bc40e -[UIViewController view] + 27
   10  UIKit                               0x00000001105d72c9 -[UIWindow addRootViewControllerViewIfPossible] + 58
   11  UIKit                               0x00000001105d768f -[UIWindow _setHidden:forced:] + 247
   12  UIKit                               0x00000001105e3e21 -[UIWindow makeKeyAndVisible] + 42
   13  UIKit                               0x0000000110587457 -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 2732
   14  UIKit                               0x000000011058a1de -[UIApplication _runWithMainScene:transitionContext:completion:] + 1349
   15  UIKit                               0x00000001105890d5 -[UIApplication workspaceDidEndTransaction:] + 179
   16  FrontBoardServices                  0x00000001133675e5 __31-[FBSSerialQueue performAsync:]_block_invoke_2 + 21
   17  CoreFoundation                      0x000000010fc2041c __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
   18  CoreFoundation                      0x000000010fc16165 __CFRunLoopDoBlocks + 341
   19  CoreFoundation                      0x000000010fc15f25 __CFRunLoopRun + 2389
   20  CoreFoundation                      0x000000010fc15366 CFRunLoopRunSpecific + 470
   21  UIKit                               0x0000000110588b42 -[UIApplication _run] + 413
   22  UIKit                               0x000000011058b900 UIApplicationMain + 1282
   23  stopwatch2                          0x000000010faf0ff7 main + 135
   24  libdyld.dylib                       0x0000000111faf145 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException   
(lldb) 

但是，这是我的实际代码：

import UIKit

class ViewController: UIViewController {

    var timer = NSTimer()
    var count = 0
    func updateTime() {
        count++
        time.text = "\(count)"
    }

    @IBOutlet var time: UILabel!

    @IBAction func pause(sender: AnyObject) {
        timer.invalidate()
    }

    @IBAction func stop(sender: AnyObject) {
        timer.invalidate()
        count = 0
        time.text = "0"
    }

    @IBAction func start(sender: AnyObject) {
        timer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: Selector("updateTime"),userInfo: nil, repeats: true)
    }

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

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

有人帮忙吗？

Answer 1

您可能将名为display的对象连接到View Controller，但随后在源代码中删除/更改了该属性。

您必须转到情节提要中的控制器，单击插座图标并删除display插座，它将带有感叹号。