UBehaviorTreeComponent::AddReferencedObjects

function AIModule Since 4.0

#include "BehaviorTree/BehaviorTreeComponent.h"

Access: public Specifiers: static

Description

Reports extra UObject references held by the behavior tree instance stack to the garbage collector. Overrides the standard UObject reference-collection hook so that objects reachable only through non-UPROPERTY internal state aren't collected prematurely.

Caveats & Gotchas

• This is a static callback wired up via UClass::AddReferencedObjects, not a virtual member you override per-instance — you almost never call or override it directly in gameplay code.
• It exists because the behavior tree instance stack holds node instance memory and object pointers outside of normal UPROPERTY reflection; skipping this hook would let the GC collect nodes still in use.
• If you subclass UBehaviorTreeComponent and add your own non-UPROPERTY UObject pointers, you must extend this function (or add proper UPROPERTY fields instead) or your objects can be garbage collected while still referenced.

Signature

static AIMODULE_API void AddReferencedObjects(UObject* InThis, FReferenceCollector& Collector);

Parameters

Name	Type	Description	Default
InThis	UObject*	The object being scanned by the garbage collector, expected to be a UBehaviorTreeComponent.	—
Collector	FReferenceCollector&	Collector used to report additional UObject references that aren't UPROPERTY-tracked.	—

Return Type

void

Example

Typical declaration in a subclass C++

class UMyBehaviorTreeComponent : public UBehaviorTreeComponent
{
    GENERATED_BODY()
public:
    static void AddReferencedObjects(UObject* InThis, FReferenceCollector& Collector)
    {
        UMyBehaviorTreeComponent* This = CastChecked<UMyBehaviorTreeComponent>(InThis);
        Collector.AddReferencedObject(This->CustomTrackedObject, This);
        Super::AddReferencedObjects(InThis, Collector);
    }
};

Version History

Introduced in: 4.0

Version	Status	Notes
5.6	stable	—

Feedback

Was this helpful?