Null check operator used on a null value

[ddxl123]

E/flutter (28395): [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: Null check operator used on a null value
E/flutter (28395): #0      BackButtonInterceptor._errorProcessing.<anonymous closure> (package:back_button_interceptor/src/back_button_interceptor.dart:26:44)
E/flutter (28395): #1      new Future.delayed.<anonymous closure> (dart:async/future.dart:427:39)
E/flutter (28395): #2      Timer._createTimer.<anonymous closure> (dart:async-patch/timer_patch.dart:18:15)
E/flutter (28395): #3      _Timer._runTimers (dart:isolate-patch/timer_impl.dart:398:19)
E/flutter (28395): #4      _Timer._handleMessage (dart:isolate-patch/timer_impl.dart:429:5)
E/flutter (28395): #5      _RawReceivePort._handleMessage (dart:isolate-patch/isolate_patch.dart:189:12)
E/flutter (28395): 

back_button_interceptor: ^6.0.2

doctor

[√] Flutter (Channel stable, 3.10.6, on Microsoft Windows [版本 10.0.22621.2134], locale zh-CN)
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[marcglasberg]

Thanks for your report.

The Null check operator used on a null value error was thrown by the interceptor you created (in your code). The error message you posted above seems to indicate an error in the back_button_interceptor package because I was catching the error and then throwing it after the async gap with throw error, which doesn't show the correct stacktrace. At the time I created that code, that was the only way to do it.

Recently, a new method Error.throwWithStackTrace(error, stackTrace)) became available, so I just published a new package version that throws the error with the correct stacktrace.

Please update the package to this new version:

   back_button_interceptor : ^7.0.0

And then run your code again. This time, you will get the correct stacktrace that shows where in your code is the problem.

I am closing this issue, but please feel free to ask follow up questions if you need.