無法識別的選擇器發送到實例與UILabel在Swift

Question

我正在寫一個應用程序在斯威夫特，跟蹤一個棒球比賽。我有超過20個需要編輯的標籤。我不斷收到「無法識別的選擇器發送到實例」錯誤。我已經在每個UILabel插座上設置了斷點，並且在第二次離開後第二次崩潰。這裏是我的app類：

var home_scores = [Int]() 
var away_scores = [Int]() 
var player_list = [String]() 
var inning = 1 
var topInning = true 
var Strikes = 0 
var balls = 0 
var outs = 0 
//Outlets for most variable text 
@IBOutlet var PlayerList: UITableView! 
@IBOutlet var StrikesText: UILabel! 
@IBOutlet var BallsText: UILabel! 
@IBOutlet var OutsText: UILabel! 
@IBOutlet var InningText: UILabel! 
@IBOutlet var InnSideText: UILabel! 
@IBOutlet var BatterName: UILabel! 

//Outlets for score text... its a lot of outlets 
//away 
@IBOutlet var away1st: UILabel! 
@IBOutlet var away2nd: UILabel! //crashes after a breakpoint here 
@IBOutlet var away3rd: UILabel! 
@IBOutlet var away4th: UILabel! 
@IBOutlet var away5th: UILabel! 
@IBOutlet var away6th: UILabel! 
@IBOutlet var away7th: UILabel! 
@IBOutlet var away8th: UILabel! 
@IBOutlet var away9th: UILabel! 
//home 
@IBOutlet var home1st: UILabel! 
@IBOutlet var home2nd: UILabel! 
@IBOutlet var home3rd: UILabel! 
@IBOutlet var home4th: UILabel! 
@IBOutlet var home5th: UILabel! 
@IBOutlet var home6th: UILabel! 
@IBOutlet var home7th: UILabel! 
@IBOutlet var home8th: UILabel! 
@IBOutlet var home9th: UILabel! 

func displayScores() { 
    away1st.text = String(away_scores[0]) 
    away2nd.text = String(away_scores[1]) 
    away3rd.text = String(away_scores[2]) 
    away4th.text = String(away_scores[3]) 
    away5th.text = String(away_scores[4]) 
    away6th.text = String(away_scores[5]) 
    away7th.text = String(away_scores[6]) 
    away8th.text = String(away_scores[7]) 
    away9th.text = String(away_scores[8]) 
    home1st.text = String(home_scores[0]) 
    home2nd.text = String(home_scores[1]) 
    home3rd.text = String(home_scores[2]) 
    home4th.text = String(home_scores[3]) 
    home5th.text = String(home_scores[4]) 
    home6th.text = String(home_scores[5]) 
    home7th.text = String(home_scores[6]) 
    home8th.text = String(home_scores[7]) 
    home9th.text = String(home_scores[8]) 
} 
@IBAction func hitStrike() { 
    Strikes += 1 
} 

這是錯誤：

2016-11-10 14:00:30.463 Base Tracker iPad[5992:325296] -[UILabel longLongValue]: unrecognized selector sent to instance 0x7fcaf1601c90 
Process 5992 resuming 
2016-11-10 14:00:30.538 Base Tracker iPad[5992:325296] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UILabel longLongValue]: unrecognized selector sent to instance 0x7fcaf1601c90' 
*** First throw call stack: 
(
    0 CoreFoundation      0x0000000105ab534b __exceptionPreprocess + 171 
    1 libobjc.A.dylib      0x0000000102dc921e objc_exception_throw + 48 
    2 CoreFoundation      0x0000000105b24f34 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132 
    3 CoreFoundation      0x0000000105a3ac15 ___forwarding___ + 1013 
    4 CoreFoundation      0x0000000105a3a798 _CF_forwarding_prep_0 + 120 
    5 Foundation       0x0000000102953faf _NSSetLongLongValueForKeyWithMethod + 63 
    6 Foundation       0x00000001028d926f -[NSObject(NSKeyValueCoding) setValue:forKey:] + 291 
    7 UIKit        0x00000001034324ef -[UIViewController setValue:forKey:] + 88 
    8 UIKit        0x00000001036a679e -[UIRuntimeOutletConnection connect] + 109 
    9 CoreFoundation      0x0000000105a5a590 -[NSArray makeObjectsPerformSelector:] + 256 
    10 UIKit        0x00000001036a5122 -[UINib instantiateWithOwner:options:] + 1867 
    11 UIKit        0x0000000103438c21 -[UIViewController _loadViewFromNibNamed:bundle:] + 386 
    12 UIKit        0x0000000103439543 -[UIViewController loadView] + 177 
    13 UIKit        0x0000000103439878 -[UIViewController loadViewIfRequired] + 201 
    14 UIKit        0x000000010343a0cc -[UIViewController view] + 27 
    15 UIKit        0x0000000103acd4be -[UIPageViewController _setViewControllers:withScrollInDirection:animated:completion:] + 591 
    16 UIKit        0x0000000103acd744 -[UIPageViewController setViewControllers:direction:animated:completion:] + 269 
    17 Base Tracker iPad     0x00000001027d0531 _TFC17Base_Tracker_iPad20MyPageViewController11viewDidLoadfT_T_ + 2609 
    18 Base Tracker iPad     0x00000001027d07f2 _TToFC17Base_Tracker_iPad20MyPageViewController11viewDidLoadfT_T_ + 34 
    19 UIKit        0x0000000103439c99 -[UIViewController loadViewIfRequired] + 1258 
    20 UIKit        0x000000010343a0cc -[UIViewController view] + 27 
    21 UIKit        0x0000000103d04bce __67-[UIStoryboardEmbedSegueTemplate newDefaultPerformHandlerForSegue:]_block_invoke + 496 
    22 UIKit        0x0000000103a72fbd -[UIStoryboardSegueTemplate _performWithDestinationViewController:sender:] + 447 
    23 UIKit        0x0000000103a72dcd -[UIStoryboardSegueTemplate _perform:] + 82 
    24 UIKit        0x0000000103a7308f -[UIStoryboardSegueTemplate perform:] + 156 
    25 UIKit        0x0000000103439a7e -[UIViewController loadViewIfRequired] + 719 
    26 UIKit        0x000000010343a0cc -[UIViewController view] + 27 
    27 UIKit        0x0000000103303c51 -[UIWindow addRootViewControllerViewIfPossible] + 71 
    28 UIKit        0x00000001033043a2 -[UIWindow _setHidden:forced:] + 293 
    29 UIKit        0x0000000103317cb5 -[UIWindow makeKeyAndVisible] + 42 
    30 UIKit        0x0000000103290c89 -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 4818 
    31 UIKit        0x0000000103296de9 -[UIApplication _runWithMainScene:transitionContext:completion:] + 1731 
    32 UIKit        0x0000000103293f69 -[UIApplication workspaceDidEndTransaction:] + 188 
    33 FrontBoardServices     0x0000000107179723 __FBSSERIALQUEUE_IS_CALLING_OUT_TO_A_BLOCK__ + 24 
    34 FrontBoardServices     0x000000010717959c -[FBSSerialQueue _performNext] + 189 
    35 FrontBoardServices     0x0000000107179925 -[FBSSerialQueue _performNextFromRunLoopSource] + 45 
    36 CoreFoundation      0x0000000105a5a311 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17 
    37 CoreFoundation      0x0000000105a3f59c __CFRunLoopDoSources0 + 556 
    38 CoreFoundation      0x0000000105a3ea86 __CFRunLoopRun + 918 
    39 CoreFoundation      0x0000000105a3e494 CFRunLoopRunSpecific + 420 
    40 UIKit        0x00000001032927e6 -[UIApplication _run] + 434 
    41 UIKit        0x0000000103298964 UIApplicationMain + 159 
    42 Base Tracker iPad     0x00000001027d79bf main + 111 
    43 libdyld.dylib      0x00000001069e268d start + 1 
) 
libc++abi.dylib: terminating with uncaught exception of type NSException 

是什麼原因造成的錯誤？我已經看到它可能是由重用的內存引起的，但這只是應用程序加載時。

Answer 1

如果故事板/筆尖文件中的一個標籤連接到視圖控制器中，並且稍後對應於該標籤連接的視圖控制器中的變量被刪除，則會發生這種情況。這可能會在storyboard/nib文件中留下標籤的懸掛引用。

我會說每個故事板/ nib文件中的每個UI元素都檢查一下，看看是否有任何變量名稱在相應的視圖控制器中沒有引用。