代码：
class LoginRegisterViewController: AutoMoveUpViewController, UITextFieldDelegate { func loginSuccessfully(){ gLog.verbose(“”) self.clearBeingLogin() if gCurUserItem.gesturePassword.isEmpty { dispatchMain_async({ let gesturePasswordVC = GesturePasswordViewController() SingletonRootNC().pushViewController(gesturePasswordVC, animated: true) }) } else { dispatchMain_async({ showMainView() }) SingletonHomeVC().getHomeStatisticInfo() SingletonHomeVC().getUncompltedTaskList() SingletonCustomerVC().getCustomerSource() SingletonCustomerVC().getCarSerieList() SingletonCustomerVC().getRegionList() let memoManagementVC = MemoManagementViewController() memoManagementVC.getCustomerdefeat() } } } |
其中，loginSuccessfully在运行的时候，是处于非主（界面）线程
对于前面几个初始化：
SingletonHomeVC().getHomeStatisticInfo() SingletonHomeVC().getUncompltedTaskList() SingletonCustomerVC().getCustomerSource() SingletonCustomerVC().getCarSerieList() SingletonCustomerVC().getRegionList() |
都是正常的，没有什么警告错误。
但是（别人写的）：
let memoManagementVC = MemoManagementViewController() memoManagementVC.getCustomerdefeat() |
却出现了警告提示：
SalesApp[34505:4106491] This application is modifying the autolayout engine from a background thread, which can lead to engine corruption and weird crashes. This will cause an exception in a future release. Stack:( 0 CoreFoundation 0x01e28494 __exceptionPreprocess + 180 1 libobjc.A.dylib 0x0167de02 objc_exception_throw + 50 2 CoreFoundation 0x01e283bd +[NSException raise:format:] + 141 3 Foundation 0x0144cf4e _AssertAutolayoutOnMainThreadOnly + 96 4 Foundation 0x012743c4 -[NSISEngine withBehaviors:performModifications:] + 26 5 Foundation 0x0127791c -[NSISEngine withAutomaticOptimizationDisabled:] + 48 6 UIKit 0x034e40e8 -[UIView(AdditionalLayoutSupport) _withAutomaticEngineOptimizationDisabledIfEngineExists:] + 75 7 UIKit 0x034e39bc __57-[UIView(AdditionalLayoutSupport) _switchToLayoutEngine:]_block_invoke + 741 8 UIKit 0x034e40f0 -[UIView(AdditionalLayoutSupport) _withAutomaticEngineOptimizationDisabledIfEngineExists:] + 83 9 UIKit 0x034e3682 -[UIView(AdditionalLayoutSupport) _switchToLayoutEngine:] + 248 10 UIKit 0x034e3585 -[UIView(AdditionalLayoutSupport) _parentalLayoutEngineDidChangeTo:] + 55 11 UIKit 0x034e3b07 __57-[UIView(AdditionalLayoutSupport) _switchToLayoutEngine:]_block_invoke_2 + 249 12 Foundation 0x01274440 -[NSISEngine withBehaviors:performModifications:] + 150 13 Foundation 0x0127791c -[NSISEngine withAutomaticOptimizationDisabled:] + 48 14 UIKit 0x034e40e8 -[UIView(AdditionalLayoutSupport) _withAutomaticEngineOptimizationDisabledIfEngineExists:] + 75 15 UIKit 0x034e39bc __57-[UIView(AdditionalLayoutSupport) _switchToLayoutEngine:]_block_invoke + 741 16 UIKit 0x034e40f0 -[UIView(AdditionalLayoutSupport) _withAutomaticEngineOptimizationDisabledIfEngineExists:] + 83 17 UIKit 0x034e3682 -[UIView(AdditionalLayoutSupport) _switchToLayoutEngine:] + 248 18 UIKit 0x034e304f -[UIView(AdditionalLayoutSupport) _initializeHostedLayoutEngine] + 728 19 UIKit 0x034d40c5 -[UIView(UIConstraintBasedLayout) _initializeLayoutEngine] + 98 20 UIKit 0x034e4021 -[UIView(AdditionalLayoutSupport) _layoutEngineCreateIfNecessary] + 73 21 UIKit 0x034d5032 -[UIView(UIConstraintBasedLayout) _tryToAddConstraint:roundingAdjustment:mutuallyExclusiveConstraints:] + 119 22 UIKit 0x034d53e8 -[UIView(UIConstraintBasedLayout) nsli_addConstraint:] + 56 23 UIKit 0x034d53a0 -[UIView(UIConstraintBasedLayout) _addConstraint:] + 304 24 UIKit 0x034d526b -[UIView(UIConstraintBasedLayout) addConstraint:] + 40 25 Cartography 0x008dd340 _TFC11Cartography10Constraint7installfT_T_ + 80 26 Cartography 0x008e9308 _TFC11Cartography15ConstraintGroup18replaceConstraintsfGSaCS_10Constraint_T_ + 360 27 Cartography 0x008e2ee9 _TF11Cartography9constrainFTCSo6UIView7replaceCS_15ConstraintGroup5blockFVS_11LayoutProxyT__S1_ + 105 28 SalesApp 0x00200904 _TFC8SalesApp22LeftLabelTableViewCellcfT13leftLabelTextSS15reuseIdentifierGSqSS_14leftLabelColorCSo7UIColor13leftLabelFontCSo6UIFont11isMandatorySb17leftLabelMaxWidthV12CoreGraphics7CGFloat_S0_ + 2644 29 SalesApp 0x000f3823 _TFC8SalesApp36LeftLabelRightTextfieldTableViewCellcfT8editableSb15reuseIdentifierGSqSS_13leftLabelTextSS11isMandatorySb18rightTextFieldTextSS25rightTextFieldPlaceholderSS23rightTextFieldTextColorCSo7UIColor22rightTextFieldTextFontCSo6UIFont22constrainToParentRightV12CoreGraphics7CGFloat_S0_ + 1347 30 SalesApp 0x000f4025 _TFC8SalesApp36LeftLabelRightTextfieldTableViewCellCfT8editableSb15reuseIdentifierGSqSS_13leftLabelTextSS11isMandatorySb18rightTextFieldTextSS25rightTextFieldPlaceholderSS23rightTextFieldTextColorCSo7UIColor22rightTextFieldTextFontCSo6UIFont22constrainToParentRightV12CoreGraphics7CGFloat_S0_ + 325 31 SalesApp 0x001d8084 _TFC8SalesApp28MemoManagementViewControllercfT15curCustomerItemGSqCS_12CustomerItem_9memotTypeGSqOS_18MemoManagementType_7curtaskGSqCS_8TaskItem_7curMemoGSqCS_4Memo_10isMemoEditGSqSb__S0_ + 3348 32 SalesApp 0x001db0a8 _TFC8SalesApp28MemoManagementViewControllerCfT15curCustomerItemGSqCS_12CustomerItem_9memotTypeGSqOS_18MemoManagementType_7curtaskGSqCS_8TaskItem_7curMemoGSqCS_4Memo_10isMemoEditGSqSb__S0_ + 136 33 SalesApp 0x002838f5 _TFC8SalesApp27LoginRegisterViewController17loginSuccessfullyfT_T_ + 965 34 SalesApp 0x0027d8ff _TFC8SalesApp27LoginRegisterViewController18getUserInfoHandlerfTGO9Alamofire6ResultV10SwiftyJSON4JSONCSo7NSError_13mergedAllParaGVs10DictionarySSPs9AnyObject___T_ + 2975 35 SalesApp 0x00284b34 _TPA.119 + 36 36 SalesApp 0x00071ef4 _TFFF8SalesApp24getUrlRespDataJson_asyncFTO9Alamofire6Method3urlSS10parametersGSqGVs10DictionarySSPs9AnyObject___7headersGSqGS2_SSSS__9extraParaGSqGS2_SSPS3____15respJsonHandlerFTGOS0_6ResultV10SwiftyJSON4JSONCSo7NSError_13mergedAllParaGS2_SSPS3____T__T_U_FT_T_U_FTGS4_S6_S7__GS2_SSPS3____T_ + 5908 37 SalesApp 0x0006822a _TPA__TFFF8SalesApp24getUrlRespDataJson_asyncFTO9Alamofire6Method3urlSS10parametersGSqGVs10DictionarySSPs9AnyObject___7headersGSqGS2_SSSS__9extraParaGSqGS2_SSPS3____15respJsonHandlerFTGOS0_6ResultV10SwiftyJSON4JSONCSo7NSError_13mergedAllParaGS2_SSPS3____T__T_U_FT_T_U_FTGS4_S6_S7__GS2_SSPS3____T_ + 154 38 SalesApp 0x0006d3b3 _TFFF8SalesApp20getUrlRespJson_asyncFTO9Alamofire6Method3urlSS10parametersGSqGVs10DictionarySSPs9AnyObject___7headersGSqGS2_SSSS__9extraParaGSqGS2_SSPS3____15respJsonHandlerFTGOS0_6ResultV10SwiftyJSON4JSONCSo7NSError_13mergedAllParaGS2_SSPS3____T__T_U_FGVS0_8ResponsePS3__S7__T_U_FT_T_ + 4787 39 SalesApp 0x000692e0 _TPA__TFFF8SalesApp20getUrlRespJson_asyncFTO9Alamofire6Method3urlSS10parametersGSqGVs10DictionarySSPs9AnyObject___7headersGSqGS2_SSSS__9extraParaGSqGS2_SSPS3____15respJsonHandlerFTGOS0_6ResultV10SwiftyJSON4JSONCSo7NSError_13mergedAllParaGS2_SSPS3____T__T_U_FGVS0_8ResponsePS3__S7__T_U_FT_T_ + 432 40 SalesApp 0x00080ed8 _TTRXFo__dT__XFdCb__dT__ + 40 41 libdispatch.dylib 0x045e1363 _dispatch_call_block_and_release + 15 42 libdispatch.dylib 0x046049cd _dispatch_client_callout + 14 43 libdispatch.dylib 0x045ea971 _dispatch_root_queue_drain + 1008 44 libdispatch.dylib 0x045ea57a _dispatch_worker_thread3 + 115 45 libsystem_pthread.dylib 0x0493225c _pthread_wqthread + 1050 46 libsystem_pthread.dylib 0x0492ff56 start_wqthread + 34 ) |
此处一直很疑惑：
为何其他那几个调用函数没有出现警告：
This application is modifying the autolayout engine from a background thread, which can lead to engine corruption and weird crashes. This will cause an exception in a future release
但是最后一个却出现了这个警告
看函数调用堆栈stack
－》通过：
_TFC8SalesApp36LeftLabelRightTextfieldTableViewCellCfT8editableSb15reuseIdentifierGSqSS_13leftLabelTextSS11isMandatorySb18rightTextFieldTextSS25rightTextFieldPlaceholderSS23rightTextFieldTextColorCSo7UIColor22rightTextFieldTextFontCSo6UIFont22constrainToParentRightV12CoreGraphics7CGFloat_S0_ + 325 31 SalesApp 0x001d8084 _TFC8SalesApp28MemoManagementViewControllercfT15curCustomerItemGSqCS_12CustomerItem_9memotTypeGSqOS_18MemoManagementType_7curtaskGSqCS_8TaskItem_7curMemoGSqCS_4Memo_10isMemoEditGSqSb__S0_ + 3348 |
基本上确定出错的地方是：
在对应的类MemoManagementViewController初始化，init的时候：
调用了LeftLabelRightTextfieldTableViewCell，从而导致出现警告的：
在非主的UI界面线程，去操作了UI界面上的东西
－》所以才报错的
－》但是之前那么多的其他的类去调用LeftLabelRightTextfieldTableViewCell，为何却没有出错呢？
最后的最后，终于有点搞明白了：
之所以：
SingletonHomeVC().getHomeStatisticInfo() SingletonHomeVC().getUncompltedTaskList() SingletonCustomerVC().getCustomerSource() SingletonCustomerVC().getCarSerieList() SingletonCustomerVC().getRegionList() |
没有出现警告的原因是：
在此处调用之前，SingletonHomeVC和SingletonCustomerVC两个实例，都已经初始化过了：
它们在初始化的时候，都是：
确保了，在主的UI界面线程中去初始化的：
分别是：
func resetHomeVC() -> HomeViewController { gLog.debug(“”) gHomeVC = HomeViewController() gHomeVC.tabBarItem = UITabBarItem(title: “首页”, image: UIImage(named: “tab_home”), tag: MainTabTagHome) gHomeVC.tabBarItem.selectedImage = UIImage(named: “tab_home_selected”) return gHomeVC } func SingletonHomeVC() -> HomeViewController { gLog.debug(“”) if gHomeVC == nil { resetHomeVC() } return gHomeVC } |
willFinishLaunchingWithOptions->resetGlobalValues->->resetHomeVC
输出是：
2016-06-23 10:07:50.855 [Debug] [main] [GlobalValues.swift:153] resetHomeVC() > |
代码：
func resetCustomerVC() -> CustomerViewController { gLog.verbose(“”) gCustomerVC = CustomerViewController() gCustomerVC.tabBarItem = UITabBarItem(title: “客户”, image: UIImage(named: “tab_customer”), tag: MainTabTagCustomer) gCustomerVC.tabBarItem.selectedImage = UIImage(named: “tab_customer_selected”) return gCustomerVC } func SingletonCustomerVC() -> CustomerViewController { gLog.verbose(“”) if gCustomerVC == nil { resetCustomerVC() } return gCustomerVC } class MainViewController: UITabBarController { override func viewDidLoad() { super.viewDidLoad() self.viewControllers = [SingletonHomeVC(), SingletonCustomerVC(), SingletonTaskVC(), reportVC] } } |
MainViewController->viewDidLoad->resetCustomerVC输出：
2016-06-23 10:10:14.147 [Verbose] [main] [GlobalValues.swift:73] resetCustomerVC() > |
而对于在loginSuccessfully中执行：
let memoManagementVC = MemoManagementViewController() |
时，时处于非主线程
－》
所以内部的init去初始化一些UI相关的内容时，才报此警告的。
－》解决办法也很简单：
确保你的类，此处的MemoManagementViewController在初始化时候，是在主界面线程的
转载请注明：在路上 » ［已解决］swift代码出现警告：This application is modifying the autolayout engine from a background thread