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I am consistently getting this error in the thousands and have no way to trap or diagnose it.
at Xamarin.Forms.Platform.iOS.NavigationRenderer+ParentingViewController.Dispose (Boolean disposing) <0x100accd70 + 0x00034> in <filename unknown>:0
at Foundation.NSObject.Dispose () <0x100b5de10 + 0x00023> in <filename unknown>:0
at Xamarin.Forms.Platform.iOS.NavigationRenderer+<>c__DisplayClass49_0+<<RemoveViewControllers>b__0>d.MoveNext () <0x100ad17b0 + 0x0023f> in <filename unknown>:0
Occurring over 2000 times in the past 30 days. Any ways you could open up some ability to diagnose this?
I can repro this albeit more rarely:
System.NullReferenceExceptionObject reference not set to an instance of an object
at Xamarin.Forms.Platform.iOS.NavigationRenderer+<>c__DisplayClass54_0+<<RemoveViewControllers>b__0>d.MoveNext () <0x100b62bdc + 0x00157> in <filename unknown>:0
Alan - did you find a fix?
This problem seemed to just fade away with updates for me. Cheers.
Would have been great to see a repro.
Can you close the ticket if the issue no longer persists? Not sure if aed still has it.
Could you please provide a simple reproduction case ?
Same problem here. A periodically ocurring crash.
We have been experiencing this crash on daily basis, 2-3 crashes per day. We get the following stacktrace in HockeyApp very time. We are using XF 184.108.40.206. Please look at the source code, line 540 in ...iOS\NavigationRenderer.cs.
PS: RemoveXFSecondaryNavBar is a simple custom renderer which I use to set BarTextColor in OnElementChanged and nothing more.
System.ObjectDisposedException: Cannot access a disposed object.
Object name: 'RemoveXFSecondaryNavBar'.
at Foundation.NSObject.get_SuperHandle () [0x0004e] in /Users/builder/data/lanes/3988/e02d2723/source/xamarin-macios/src/Foundation/NSObject2.cs:423
at UIKit.UINavigationController.get_ViewControllers () [0x00030] in /Users/builder/data/lanes/3988/e02d2723/source/xamarin-macios/src/build/ios/native/UIKit/UINavigationController.g.cs:557
at Xamarin.Forms.Platform.iOS.NavigationRenderer+<>c__DisplayClass57_0+<<RemoveViewControllers>b__0>d.MoveNext () [0x00030] in C:\BuildAgent2\work\ca3766cfc22354a1\Xamarin.Forms.Platform.iOS\Renderers\NavigationRenderer.cs:540
Hey guys, I still have this issue with XF version 220.127.116.11. Same exception as above. (different code line number though)
It is this line in the source code:
@sh.naz we are still waiting for a sample project triggering the issue.
Because it is a periodically occuring error, we have not yet been able to create a sample project which can be used to recreate the crash consistently.
But the error occurs 3-4 times daily in our apps.
We are going to close this for the time being as not reproducible until we can receive a reproduction project. You are welcome to reopen this ticket when you are able to provide us with one for further investigation.
The crash occurs where sh.naz says it does.
We also have two apps on the app store and this is the most frequent crash. It's very hard to repro locally.
XF team, can you just do a null check or a try/catch around that line, even if you don't have a repro. It looks like a synchronization issue.
The issue still happens sometimes in XF v18.104.22.1687.
It looks like the actual line, that causes this exception is https://github.com/xamarin/Xamarin.Forms/blob/release-2.3.4-sr3/Xamarin.Forms.Platform.iOS/Renderers/NavigationRenderer.cs#L841 . As for me, it's very obvious place of a crash.