UINavigation推送相同的视图控制器两次错误

如何解决UINavigation推送相同的视图控制器两次错误

将视图控制器推入堆栈时出现以下错误：

Thread 1: Exception: "<UINavigationController: 0x7f9345817a00> is pushing the same view controller instance (<xxxx.HelpViewController: 0x7f9346143390>) more than once which is not supported and is most likely an error in the application : com.xxx.xxx1"

我正在使用以下代码从表视图控制器中调用视图控制器：

let myVC = self.storyboard?.instantiateViewController(identifier: "HelpViewController") as! HelpViewController
                // pass any parms here
                myVC.stringPassed = label!.text!
                navigationController?.pushViewController(myVC,animated: true)
                self.navigationController!.pushViewController(myVC,animated: false)

我只有一个视图控制器副本，这是我第一次将此视图推入堆栈。

任何帮助将不胜感激。

这是日志：

2020-08-13 17:42:45.289742-0500 NCLEX[29470:2944371] *** Terminating app due to uncaught exception 'NSInvalidArgumentException',reason: '<UINavigationController: 0x7f94e980ce00> is pushing the same view controller instance (<xxx.HelpViewController: 0x7f94e54634a0>) more than once which is not supported and is most likely an error in the application : com.xxx.xxx'
*** First throw call stack:
(
    0   CoreFoundation                      0x00007fff23e3de6e __exceptionPreprocess + 350
    1   libobjc.A.dylib                     0x00007fff512539b2 objc_exception_throw + 48
    2   UIKitCore                           0x00007fff48be2df6 -[UINavigationController pushViewController:transition:forceImmediate:] + 451
    3   UIKitCore                           0x00007fff48be2a9f -[UINavigationController pushViewController:animated:] + 669
    4   UIKitCore                           0x00007fff48ca880d -[_UIViewControllerTransitionCoordinator _applyBlocks:releaseBlocks:] + 294
    5   UIKitCore                           0x00007fff48ca495b -[_UIViewControllerTransitionContext _runAlongsideCompletions] + 126
    6   UIKitCore                           0x00007fff48ca46cf -[_UIViewControllerTransitionContext completeTransition:] + 106
    7   UIKitCore                           0x00007fff48cb6e1f __53-[_UINavigationParallaxTransition animateTransition:]_block_invoke.158 + 806
    8   UIKitCore                           0x00007fff4982093c -[UIViewAnimationBlockDelegate _didEndBlockAnimation:finished:context:] + 671
    9   UIKitCore                           0x00007fff497f15c9 -[UIViewAnimationState sendDelegateAnimationDidStop:finished:] + 220
    10  UIKitCore                           0x00007fff497f1bc0 -[UIViewAnimationState animationDidStop:finished:] + 276
    11  UIKitCore                           0x00007fff497f1d46 -[UIViewAnimationState animationDidStop:finished:] + 666
    12  QuartzCore                          0x00007fff2b4fbadc _ZN2CA5Layer23run_animation_callbacksEPv + 306
    13  libdispatch.dylib                   0x0000000110475e8e _dispatch_client_callout + 8
    14  libdispatch.dylib                   0x0000000110483d97 _dispatch_main_queue_callback_4CF + 1149
    15  CoreFoundation                      0x00007fff23da1869 __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 9
    16  CoreFoundation                      0x00007fff23d9c3b9 __CFRunLoopRun + 2041
    17  CoreFoundation                      0x00007fff23d9b8a4 CFRunLoopRunSpecific + 404
    18  GraphicsServices                    0x00007fff38c39bbe GSEventRunModal + 139
    19  UIKitCore                           0x00007fff49325968 UIApplicationMain + 1605
    20  NCLEX                               0x000000010f37007b main + 75
    21  libdyld.dylib                       0x00007fff520ce1fd start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException

解决方法

如果您不需要动画，则需要在这2条注释中添加1条注释，主要是第二条注释

navigationController?.pushViewController(myVC,animated: true)
self.navigationController!.pushViewController(myVC,animated: false)

因为他们做同样的事情，两次推入相同的vc会导致崩溃