[Bug] iOS Crash, Shell.GetNavBarIsVisible: 'SIGABRT' for 'Object reference not set to an instance of an object'

inimirpaz commented 3 years ago

Description

I have been experiencing a lot of crash issues on iOS due to a Xamarin.Forms.Shell.GetNavBarIsVisible call.

E.g.

``` Hardware Model: iPhone9,3 Code Type: arm64 Parent Process: [1] Date/Time: 2021-02-28T09:42:13.999Z Launch Time: 2021-02-28T09:03:09Z OS Version: iPhone OS 14.4 (18D52) Report Version: 104 Exception Type: SIGABRT Exception Codes: #0 at 0x1bb14c84c Crashed Thread: 0 Application Specific Information: *** Terminating app due to uncaught exception 'SIGABRT', reason: 'Object reference not set to an instance of an object' Xamarin Exception Stack: System.NullReferenceException: Object reference not set to an instance of an object at Xamarin.Forms.Shell.GetNavBarIsVisible (Xamarin.Forms.BindableObject obj) <0x10555ece0 + 0x00024> in <978ec34c5c9c4c4eb3d73b6da958bcd6#b512393cfcba0fe683ad3901c90fd1a0>:0 at Xamarin.Forms.Platform.iOS.ShellSectionRenderer+NavDelegate.WillShowViewController (UIKit.UINavigationController navigationController, UIKit.UIViewController viewController, System.Boolean animated) <0x1062e6080 + 0x000c7> in :0 at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain(int,string[],intptr,intptr) at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) <0x1060165e0 + 0x0002f> in <605c9d1d803040f889fdbf69630efe9f#b512393cfcba0fe683ad3901c90fd1a0>:0 at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) <0x106016550 + 0x00043> in <605c9d1d803040f889fdbf69630efe9f#b512393cfcba0fe683ad3901c90fd1a0>:0 at TestApp.iOS.Application.Main (System.String[] args) <0x105022b50 + 0x00023> in <562923ba70544658b1da7997e42bb2a6#b512393cfcba0fe683ad3901c90fd1a0>:0 Thread 0 Crashed: 0 libsystem_kernel.dylib 0x00000001bb14c84c __pthread_kill + 8 1 libsystem_c.dylib 0x0000000197f088f4 abort + 96 2 TestApp.iOS 0x00000001071ba9b0 0x104fa8000 + 35727792 3 TestApp.iOS 0x000000010707f900 0x104fa8000 + 34437376 4 TestApp.iOS 0x00000001070146cc 0x104fa8000 + 33998540 5 TestApp.iOS 0x00000001070130b4 0x104fa8000 + 33992884 6 TestApp.iOS 0x00000001070093b8 0x104fa8000 + 33952696 7 TestApp.iOS 0x00000001062e6148 0x104fa8000 + 20177224 8 TestApp.iOS 0x00000001062e6148 0x104fa8000 + 20177224 9 TestApp.iOS 0x00000001053bfca0 0x104fa8000 + 4291744 10 TestApp.iOS 0x00000001070262f0 0x104fa8000 + 34071280 11 TestApp.iOS 0x00000001070e1a14 0x104fa8000 + 34839060 12 TestApp.iOS 0x00000001070e5278 0x104fa8000 + 34853496 13 TestApp.iOS 0x000000010500024c 0x104fa8000 + 361036 14 TestApp.iOS 0x000000010500a9c0 0x104fa8000 + 403904 15 UIKitCore 0x00000001912ff270 -[UINavigationController _startTransition:fromViewController:toViewController:] + 1424 16 UIKitCore 0x00000001912ffc60 -[UINavigationController _startDeferredTransitionIfNeeded:] + 872 17 UIKitCore 0x0000000191300fe0 -[UINavigationController __viewWillLayoutSubviews] + 160 18 UIKitCore 0x00000001912e3e78 -[UILayoutContainerView layoutSubviews] + 220 19 UIKitCore 0x0000000191f82398 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 2464 20 QuartzCore 0x0000000192487df4 -[CALayer layoutSublayers] + 284 21 QuartzCore 0x000000019248e398 CA::Layer::layout_if_needed(CA::Transaction*) + 516 22 QuartzCore 0x00000001924996e8 CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 136 23 QuartzCore 0x00000001923e4d7c CA::Context::commit_transaction(CA::Transaction*, double, double*) + 412 24 QuartzCore 0x000000019240ef40 CA::Transaction::commit() + 724 25 QuartzCore 0x00000001924101f0 CA::Transaction::observer_callback(__CFRunLoopObserver*, unsigned long, void*) + 88 26 CoreFoundation 0x000000018f18c87c __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 28 27 CoreFoundation 0x000000018f186f50 __CFRunLoopDoObservers + 600 28 CoreFoundation 0x000000018f187498 __CFRunLoopRun + 956 29 CoreFoundation 0x000000018f186ba0 CFRunLoopRunSpecific + 568 30 GraphicsServices 0x00000001a5eef598 GSEventRunModal + 156 31 UIKitCore 0x0000000191a782f4 -[UIApplication _run] + 1048 32 UIKitCore 0x0000000191a7d874 UIApplicationMain + 160 33 TestApp.iOS 0x00000001060d20f8 0x104fa8000 + 17998072 34 TestApp.iOS 0x0000000106016610 0x104fa8000 + 17229328 35 TestApp.iOS 0x0000000106016594 0x104fa8000 + 17229204 36 TestApp.iOS 0x0000000105022b74 0x104fa8000 + 502644 37 TestApp.iOS 0x00000001053bfca0 0x104fa8000 + 4291744 38 TestApp.iOS 0x00000001070262f0 0x104fa8000 + 34071280 39 TestApp.iOS 0x00000001070e1a14 0x104fa8000 + 34839060 40 TestApp.iOS 0x00000001070e7c6c 0x104fa8000 + 34864236 41 TestApp.iOS 0x0000000107004884 0x104fa8000 + 33933444 42 TestApp.iOS 0x00000001071c2424 0x104fa8000 + 35759140 43 TestApp.iOS 0x0000000105022acc 0x104fa8000 + 502476 44 libdyld.dylib 0x000000018ee65568 start + 0 ```

Steps to Reproduce

N/A

Basic Information

Version with issue: 5.0

rachelkang commented 3 years ago

Hi, @inimirpaz - thanks for submitting this issue. Would you be able to share your project or a sample project reproducing the issue so that we can take a closer look? Thanks :)

inimirpaz commented 3 years ago

Hi, @rachelkang , I am not able to share a project. Is there anything we can add to make it more debugable? What should we be keeping an eye on? (e.g. Navigation.Push/Pop, ... ?)

We have a lot of this issue reports but they have basically the same details... Here's another one

Hardware Model: iPhone11,8 Code Type: arm64 Parent Process: [1] Date/Time: 2021-04-17T17:19:06.999Z Launch Time: 2021-04-17T17:16:24Z OS Version: iPhone OS 14.4.2 (18D70) Report Version: 104 Exception Type: SIGABRT Exception Codes: #0 at 0x1b2275414 Crashed Thread: 0 Application Specific Information: *** Terminating app due to uncaught exception 'SIGABRT', reason: 'Object reference not set to an instance of an object' Xamarin Exception Stack: System.NullReferenceException: Object reference not set to an instance of an object at Xamarin.Forms.Shell.GetNavBarIsVisible (Xamarin.Forms.BindableObject obj) <0x10284ace0 + 0x00024> in <978ec34c5c9c4c4eb3d73b6da958bcd6#e7885529838117dbc94526679c26b166>:0 at Xamarin.Forms.Platform.iOS.ShellSectionRenderer+NavDelegate.WillShowViewController (UIKit.UINavigationController navigationController, UIKit.UIViewController viewController, System.Boolean animated) <0x1035c7810 + 0x000c7> in :0 at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain(int,string[],intptr,intptr) at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) <0x103300240 + 0x0002f> in :0 at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) <0x1033001b0 + 0x00043> in :0 at TestApp.iOS.Application.Main (System.String[] args) <0x10230eb60 + 0x00023> in <1211f366acca4166ad746ca13074fb3a#e7885529838117dbc94526679c26b166>:0 Thread 0 Crashed: 0 libsystem_kernel.dylib 0x00000001b2275414 0x1b224d000 + 164884 1 libsystem_c.dylib 0x000000018d753b74 0x18d6dd000 + 486260 2 TestApp.iOS 0x000000010449d97c 0x102294000 + 35690876 3 TestApp.iOS 0x00000001043628d0 0x102294000 + 34400464 4 TestApp.iOS 0x00000001042f769c 0x102294000 + 33961628 5 TestApp.iOS 0x00000001042f6084 0x102294000 + 33955972 6 TestApp.iOS 0x00000001042ec388 0x102294000 + 33915784 7 TestApp.iOS 0x00000001035c78d8 0x102294000 + 20134104 8 TestApp.iOS 0x00000001035c78d8 0x102294000 + 20134104 9 TestApp.iOS 0x00000001026abca0 0x102294000 + 4291744 10 TestApp.iOS 0x00000001043092c0 0x102294000 + 34034368 11 TestApp.iOS 0x00000001043c49e4 0x102294000 + 34802148 12 TestApp.iOS 0x00000001043c8248 0x102294000 + 34816584 13 TestApp.iOS 0x00000001022ec24c 0x102294000 + 361036 14 TestApp.iOS 0x00000001022f69c0 0x102294000 + 403904 15 UIKitCore 0x00000001864f61b8 0x186112000 + 4080056 16 UIKitCore 0x00000001864f6bac 0x186112000 + 4082604 17 UIKitCore 0x00000001864f7f88 0x186112000 + 4087688 18 UIKitCore 0x00000001864d9a18 0x186112000 + 3963416 19 UIKitCore 0x0000000187227ec4 0x186112000 + 17915588 20 QuartzCore 0x0000000187742644 0x1875e3000 + 1439300 21 QuartzCore 0x0000000187742b18 0x1875e3000 + 1440536 22 QuartzCore 0x000000018775730c 0x1875e3000 + 1524492 23 QuartzCore 0x000000018769c640 0x1875e3000 + 759360 24 QuartzCore 0x00000001876c7b08 0x1875e3000 + 936712 25 QuartzCore 0x00000001876c8e98 0x1875e3000 + 941720 26 CoreFoundation 0x00000001842a0358 0x184200000 + 656216 27 CoreFoundation 0x000000018429a5c4 0x184200000 + 632260 28 CoreFoundation 0x000000018429ab74 0x184200000 + 633716 29 CoreFoundation 0x000000018429a21c 0x184200000 + 631324 30 GraphicsServices 0x000000019be64784 0x19be61000 + 14212 31 UIKitCore 0x0000000186cdaee8 0x186112000 + 12357352 32 UIKitCore 0x0000000186ce075c 0x186112000 + 12379996 33 TestApp.iOS 0x00000001033b3868 0x102294000 + 17954920 34 TestApp.iOS 0x0000000103300270 0x102294000 + 17220208 35 TestApp.iOS 0x00000001033001f4 0x102294000 + 17220084 36 TestApp.iOS 0x000000010230eb84 0x102294000 + 502660 37 TestApp.iOS 0x00000001026abca0 0x102294000 + 4291744 38 TestApp.iOS 0x00000001043092c0 0x102294000 + 34034368 39 TestApp.iOS 0x00000001043c49e4 0x102294000 + 34802148 40 TestApp.iOS 0x00000001043cac3c 0x102294000 + 34827324 41 TestApp.iOS 0x00000001042e7854 0x102294000 + 33896532 42 TestApp.iOS 0x00000001044a540c 0x102294000 + 35722252 43 TestApp.iOS 0x000000010230eae0 0x102294000 + 502496 44 libdyld.dylib 0x0000000183f5a6b0 0x183f59000 + 5808 Thread 1: 0 libsystem_kernel.dylib 0x00000001b22751ac 0x1b224d000 + 164268 1 TestApp.iOS 0x0000000104468354 0x102294000 + 35472212 2 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 3 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 2: 0 libsystem_kernel.dylib 0x00000001b225130c 0x1b224d000 + 17164 1 TestApp.iOS 0x00000001044129d0 0x102294000 + 35121616 2 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 3 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 4 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 3: 0 libsystem_kernel.dylib 0x00000001b22512d0 0x1b224d000 + 17104 1 CoreFoundation 0x00000001842a0c30 0x184200000 + 658480 2 CoreFoundation 0x000000018429ac14 0x184200000 + 633876 3 CoreFoundation 0x000000018429a21c 0x184200000 + 631324 4 Foundation 0x0000000185549df0 0x185541000 + 36336 5 Foundation 0x0000000185549cbc 0x185541000 + 36028 6 UIKitCore 0x0000000186d8ec48 0x186112000 + 13093960 7 Foundation 0x00000001856bba34 0x185541000 + 1550900 8 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 9 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 4: 0 libsystem_kernel.dylib 0x00000001b2251324 0x1b224d000 + 17188 1 TestApp.iOS 0x00000001044129d0 0x102294000 + 35121616 2 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 3 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 4 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 5: 0 libsystem_kernel.dylib 0x00000001b2251324 0x1b224d000 + 17188 1 TestApp.iOS 0x00000001044129d0 0x102294000 + 35121616 2 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 3 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 4 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 6: 0 libsystem_kernel.dylib 0x00000001b22751ac 0x1b224d000 + 164268 1 TestApp.iOS 0x0000000104477ae4 0x102294000 + 35535588 2 TestApp.iOS 0x000000010441e048 0x102294000 + 35168328 3 TestApp.iOS 0x000000010441df20 0x102294000 + 35168032 4 TestApp.iOS 0x000000010441e144 0x102294000 + 35168580 5 TestApp.iOS 0x000000010440cf1c 0x102294000 + 35098396 6 TestApp.iOS 0x00000001043872b8 0x102294000 + 34550456 7 TestApp.iOS 0x0000000102418fa8 0x102294000 + 1593256 8 TestApp.iOS 0x0000000102418b14 0x102294000 + 1592084 9 TestApp.iOS 0x000000010241861c 0x102294000 + 1590812 10 TestApp.iOS 0x00000001024185cc 0x102294000 + 1590732 11 TestApp.iOS 0x00000001024184cc 0x102294000 + 1590476 12 TestApp.iOS 0x0000000102418578 0x102294000 + 1590648 13 TestApp.iOS 0x000000010241b934 0x102294000 + 1603892 14 TestApp.iOS 0x000000010241207c 0x102294000 + 1564796 15 TestApp.iOS 0x000000010240fbac 0x102294000 + 1555372 16 TestApp.iOS 0x000000010240f9ac 0x102294000 + 1554860 17 TestApp.iOS 0x000000010240f930 0x102294000 + 1554736 18 TestApp.iOS 0x00000001024121e4 0x102294000 + 1565156 19 TestApp.iOS 0x00000001026abca0 0x102294000 + 4291744 20 TestApp.iOS 0x00000001043092c0 0x102294000 + 34034368 21 TestApp.iOS 0x00000001043c49e4 0x102294000 + 34802148 22 TestApp.iOS 0x00000001043ca2d0 0x102294000 + 34824912 23 TestApp.iOS 0x0000000104412ac8 0x102294000 + 35121864 24 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 25 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 26 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 7: 0 libsystem_kernel.dylib 0x00000001b227570c 0x1b224d000 + 165644 1 TestApp.iOS 0x0000000104403f5c 0x102294000 + 35061596 2 TestApp.iOS 0x0000000104403924 0x102294000 + 35060004 3 TestApp.iOS 0x00000001044129d0 0x102294000 + 35121616 4 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 5 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 6 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 8: 0 libsystem_kernel.dylib 0x00000001b2251324 0x1b224d000 + 17188 1 TestApp.iOS 0x00000001044129d0 0x102294000 + 35121616 2 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 3 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 4 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 9: 0 libsystem_kernel.dylib 0x00000001b22751ac 0x1b224d000 + 164268 1 TestApp.iOS 0x0000000104477b0c 0x102294000 + 35535628 2 TestApp.iOS 0x000000010441e048 0x102294000 + 35168328 3 TestApp.iOS 0x000000010441df20 0x102294000 + 35168032 4 TestApp.iOS 0x00000001043b6d38 0x102294000 + 34745656 5 TestApp.iOS 0x000000010438589c 0x102294000 + 34543772 6 TestApp.iOS 0x0000000102411768 0x102294000 + 1562472 7 TestApp.iOS 0x0000000102411820 0x102294000 + 1562656 8 TestApp.iOS 0x000000010241130c 0x102294000 + 1561356 9 TestApp.iOS 0x0000000102411360 0x102294000 + 1561440 10 TestApp.iOS 0x000000010240c288 0x102294000 + 1540744 11 TestApp.iOS 0x000000010240bfec 0x102294000 + 1540076 12 TestApp.iOS 0x0000000102cd69f0 0x102294000 + 10758640 13 TestApp.iOS 0x0000000102cd67e8 0x102294000 + 10758120 14 TestApp.iOS 0x0000000102cd671c 0x102294000 + 10757916 15 TestApp.iOS 0x000000010356f4c4 0x102294000 + 19772612 16 TestApp.iOS 0x000000010241207c 0x102294000 + 1564796 17 TestApp.iOS 0x000000010240fbac 0x102294000 + 1555372 18 TestApp.iOS 0x000000010240f9ac 0x102294000 + 1554860 19 TestApp.iOS 0x000000010240f930 0x102294000 + 1554736 20 TestApp.iOS 0x00000001024121e4 0x102294000 + 1565156 21 TestApp.iOS 0x00000001026abca0 0x102294000 + 4291744 22 TestApp.iOS 0x00000001043092c0 0x102294000 + 34034368 23 TestApp.iOS 0x00000001043c49e4 0x102294000 + 34802148 24 TestApp.iOS 0x00000001043ca2d0 0x102294000 + 34824912 25 TestApp.iOS 0x0000000104412ac8 0x102294000 + 35121864 26 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 27 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 28 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 10: 0 libsystem_kernel.dylib 0x00000001b22512d0 0x1b224d000 + 17104 1 CoreFoundation 0x00000001842a0c30 0x184200000 + 658480 2 CoreFoundation 0x000000018429ac14 0x184200000 + 633876 3 CoreFoundation 0x000000018429a21c 0x184200000 + 631324 4 CFNetwork 0x0000000184b701c0 0x184924000 + 2408896 5 Foundation 0x00000001856bba34 0x185541000 + 1550900 6 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 7 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 11: 0 libsystem_kernel.dylib 0x00000001b22512d0 0x1b224d000 + 17104 1 CoreFoundation 0x00000001842a0c30 0x184200000 + 658480 2 CoreFoundation 0x000000018429ac14 0x184200000 + 633876 3 CoreFoundation 0x000000018429a21c 0x184200000 + 631324 4 AudioSession 0x000000018bde30c4 0x18bdd6000 + 53444 5 AudioSession 0x000000018bde525c 0x18bdd6000 + 62044 6 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 7 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 12: 0 libsystem_kernel.dylib 0x00000001b2251324 0x1b224d000 + 17188 1 TestApp.iOS 0x00000001044129d0 0x102294000 + 35121616 2 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 3 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 4 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 13: 0 libsystem_kernel.dylib 0x00000001b2251324 0x1b224d000 + 17188 1 TestApp.iOS 0x00000001044129d0 0x102294000 + 35121616 2 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 3 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 4 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 14: 0 libsystem_kernel.dylib 0x00000001b2276184 0x1b224d000 + 168324 1 libsystem_pthread.dylib 0x00000001cfdd876c 0x1cfdce000 + 42860 Thread 15: 0 libsystem_kernel.dylib 0x00000001b2251324 0x1b224d000 + 17188 1 TestApp.iOS 0x00000001044129d0 0x102294000 + 35121616 2 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 3 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 4 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 16: 0 ??? 0x0000000000000000 0x0 + 0 Thread 17: 0 libsystem_kernel.dylib 0x00000001b22751ac 0x1b224d000 + 164268 1 TestApp.iOS 0x0000000104477ae4 0x102294000 + 35535588 2 TestApp.iOS 0x00000001044807c4 0x102294000 + 35571652 3 TestApp.iOS 0x0000000104406bb0 0x102294000 + 35072944 4 TestApp.iOS 0x00000001044129d0 0x102294000 + 35121616 5 TestApp.iOS 0x0000000104412854 0x102294000 + 35121236 6 libsystem_pthread.dylib 0x00000001cfdcfcb0 0x1cfdce000 + 7344 7 libsystem_pthread.dylib 0x00000001cfdd8778 0x1cfdce000 + 42872 Thread 0 crashed with arm64 Thread State: x21: 0x0000000104a5b9a0 x2: 0x0000000000000000 x16: 0x0000000000000148 x3: 0x0000000000000000 x22: 0x0000000105705730 x4: 0x0000000000000008 x17: 0x0000000104a5b8c0 cpsr: 0x0000000040000000 x5: 0x00000001103cbc00 x23: 0x0000000107823950 x6: 0x0000000000000600 x18: 0x000000011a2f5d8c x10: 0x0000000000bf3d00 lr: 0x00000001cfdd0b50 x7: 0x0000000000001d00 x24: 0x00000001103fa0c8 x11: 0x00000001103cc000 x8: 0x00000000000005b9 x19: 0x0000000000000006 x25: 0x000000010a84f348 x9: 0x86d5241ca1923076 x12: 0x0000000000004009 fp: 0x000000016db656c0 x26: 0x0000000107823a00 x13: 0x0000000000003fff pc: 0x00000001b2275414 x27: 0x0000000000000008 x14: 0x0000000000001e1d x20: 0x0000000000000407 x0: 0x0000000000000000 sp: 0x000000016db656a0 x28: 0x00000001026abc9f x15: 0x0000000000003318 x1: 0x0000000000000000 Binary Images: 0x0000000102294000 - 0x00000001045dbfff +TestApp.iOS arm64 /private/var/containers/Bundle/Application/27656804-415B-43AA-B094-0C311FDBC40D/TestApp.iOS.app/TestApp.iOS 0x0000000104930000 - 0x0000000104937fff +MDFInternationalization arm64 <89c3c1a37d893f2a8095c0709251b1aa> /private/var/containers/Bundle/Application/27656804-415B-43AA-B094-0C311FDBC40D/TestApp.iOS.app/Frameworks/MDFInternationalization.framework/MDFInternationalization 0x0000000104944000 - 0x000000010494bfff +MDFTextAccessibility arm64 <31ff5456976c30598ff7d21bcede1b8a> /private/var/containers/Bundle/Application/27656804-415B-43AA-B094-0C311FDBC40D/TestApp.iOS.app/Frameworks/MDFTextAccessibility.framework/MDFTextAccessibility 0x0000000104958000 - 0x0000000104963fff +MotionAnimator arm64 /private/var/containers/Bundle/Application/27656804-415B-43AA-B094-0C311FDBC40D/TestApp.iOS.app/Frameworks/MotionAnimator.framework/MotionAnimator 0x0000000104970000 - 0x0000000104977fff +MotionInterchange arm64 <2db66df13b893abdadb3f3c9e52e0b1d> /private/var/containers/Bundle/Application/27656804-415B-43AA-B094-0C311FDBC40D/TestApp.iOS.app/Frameworks/MotionInterchange.framework/MotionInterchange 0x0000000104984000 - 0x000000010498ffff +MotionTransitioning arm64 <3c30d94c72b23d5cbcba15ca06686e16> /private/var/containers/Bundle/Application/27656804-415B-43AA-B094-0C311FDBC40D/TestApp.iOS.app/Frameworks/MotionTransitioning.framework/MotionTransitioning 0x0000000104aa0000 - 0x0000000104f17fff +libSkiaSharp arm64 /private/var/containers/Bundle/Application/27656804-415B-43AA-B094-0C311FDBC40D/TestApp.iOS.app/Frameworks/libSkiaSharp.framework/libSkiaSharp 0x0000000104f78000 - 0x00000001050b3fff +MaterialComponents arm64 <5c3d09450aa932cca48acb35ead7f2f7> /private/var/containers/Bundle/Application/27656804-415B-43AA-B094-0C311FDBC40D/TestApp.iOS.app/Frameworks/MaterialComponents.framework/MaterialComponents 0x0000000183f59000 - 0x0000000183f93fff libdyld.dylib arm64e <21b19919133438bcb233896e929945e0> /usr/lib/system/libdyld.dylib 0x0000000184200000 - 0x00000001845b9fff CoreFoundation arm64e <727f2644eb4e3d57bc2ee6803ba92366> /System/Library/Frameworks/CoreFoundation.framework/CoreFoundation 0x0000000184924000 - 0x0000000184dbbfff CFNetwork arm64e <0ebb3119a8ce35da96245b5528802fc8> /System/Library/Frameworks/CFNetwork.framework/CFNetwork 0x0000000185541000 - 0x00000001857fcfff Foundation arm64e <7698bf3e0cf631c085e9562714f01276> /System/Library/Frameworks/Foundation.framework/Foundation 0x0000000186112000 - 0x00000001875bffff UIKitCore arm64e <8518eae3832b3ff09fa59dbe3041f26c> /System/Library/PrivateFrameworks/UIKitCore.framework/UIKitCore 0x00000001875e3000 - 0x0000000187869fff QuartzCore arm64e <8510f13908243686a9aa3e198539a021> /System/Library/Frameworks/QuartzCore.framework/QuartzCore 0x000000018bdd6000 - 0x000000018bdeefff AudioSession arm64e /System/Library/PrivateFrameworks/AudioSession.framework/AudioSession 0x000000018d6dd000 - 0x000000018d75bfff libsystem_c.dylib arm64e <961a8fb0de8a3567b4375d99cd549fae> /usr/lib/system/libsystem_c.dylib 0x000000019be61000 - 0x000000019be69fff GraphicsServices arm64e <1959c615fa0830de8461884a5bbc8037> /System/Library/PrivateFrameworks/GraphicsServices.framework/GraphicsServices 0x00000001b224d000 - 0x00000001b227efff libsystem_kernel.dylib arm64e /usr/lib/system/libsystem_kernel.dylib 0x00000001cfdce000 - 0x00000001cfdd9fff libsystem_pthread.dylib arm64e /usr/lib/system/libsystem_pthread.dylib

Kukkimonsuta commented 3 years ago

We just encoutered this issue as well, it points to this code - _self.ElementForViewController(viewController); can evaluate to null which is not acceptable for navBarVisible = Shell.GetNavBarIsVisible(element);. I'll try to put together minimal repro project.

https://github.com/xamarin/Xamarin.Forms/blob/ad71f116ed5a5d8402bbd25dbf0b96bb7821d5e1/Xamarin.Forms.Platform.iOS/Renderers/ShellSectionRenderer.cs#L622-L628

Kukkimonsuta commented 3 years ago

Minimal reproduction steps I've been able to find - https://github.com/Kukkimonsuta/xamarin-forms-14125 - keep clicking buttons till the problem occurs.

1) use shell 2) use Navigation.PushAsync to go to another page 3) use Navigation.PushModalAsync to open modal 4) run async handler (ex. button click) with some more async calls 5) call Shell.Current.GoToAsync to another item

Bug occurs here: https://github.com/Kukkimonsuta/xamarin-forms-14125/blob/1b951c0a3cad5e97ccae5cc81b32605d4c933211/xamarin-forms-14125/Views/LogoutPage.xaml.cs#L17-L23

hetcmnten commented 3 years ago

I just encounter this as well, but only have some log from production so too hard to tell which step

madtownchris commented 3 years ago

This is a big problem for our app. 8x last 7 days and not very many users at the moment. Any workarounds? I tried making some other stuff in functions that call Shell.GoToAsync not async but it's unclear if that helps.

InquisitorJax commented 3 years ago

related? https://github.com/xamarin/Xamarin.Forms/issues/14122 We're also seeing a bunch of these errors in App Center - unable to reproduce locally.

trj2059 commented 1 year ago

This error is still being generated. Not only is it being generated for Xamarin forms, but we are seeing it in MAUI with .NET 6 and 7.

WilliamWatterson86 commented 1 year ago

@trj2059 - did you find a solution for your maui issue? Seeing this in my project too

1c3f0x84 commented 1 year ago

Created pull request for this in maui

xamarin / Xamarin.Forms