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Blackboard Component becomes nullptr error.

Hi Everyone.

I have a small issue with a Blackboard component from a behavior tree that when I try to set a value from the blackboard, the blackboard at that moment is a nullptr reference, I'm not sure what is causing this behavior to happen since I haven't deleted at any moment the AI Actor nor anything related to it.

In this Screenshot you can see that the Blackboard component exists and is not a nullptr reference. alt text

In this one is the same blackboard after it got Initialized without any problem. alt text

And in this one you can see the error it generates when I try to read the Blackboard to try and set some values. alt text

But I can't set the values since for some reason the Blackboard is getting deleted or loosing it's reference, any help with this issue would be greatly appreciated.

Thank you.

Product Version: UE 4.14
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asked Jan 22 '17 at 03:37 PM in C++ Programming

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WolfAlvein
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2 answers: sort voted first

Hi Mieszko.

I have finally been able to solve this problem and it seems the issue was happening since in the constructor of my actor I had commented the following lines:

 AIControllerClass = ASubjectsAI::StaticClass();
 AutoPossessAI = EAutoPossessAI::PlacedInWorldOrSpawned;

So once I implemented this lines again the error was gone.

Thank you.

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answered Jan 25 '17 at 06:59 PM

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WolfAlvein
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At no point does the AIController.Blackboard get cleared, once created. Which leads me to believe that you call your SetSubjectJobon something else than you expect. I'd double check that if I were you ;)

But if that's not the case you can always use VS' data breakpoint to observe changes done to AIController.Blackboard. If you find the pointer being cleared follow up in this thread, please.

Cheers,

--mieszko

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answered Jan 22 '17 at 07:18 PM

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MieszkoZ STAFF
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