Component overlap delegates not working

Development World Creation
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1

I’m trying to set up a drop object that the player can pick up if he enters a trigger component of the drop. This should be fairly easy to manage with only C++ code, the class is created as normal but for some reason I can’t add a dynamic to OnComponentBeginOverlap. Here’s my code:

Header

UCLASS()
class PROJECTWAIFU_API ADrop : public AActor
{
	GENERATED_BODY()
	
public:	
	// Sets default values for this actor's properties
	ADrop();

	// Called when the game starts or when spawned
	virtual void BeginPlay() override;
	
	// Called every frame
	virtual void Tick( float DeltaSeconds ) override;

	UPROPERTY(VisibleAnywhere)
	USphereComponent* grabBox;
	
	UFUNCTION()
	void OnOverlapBegin(UPrimitiveComponent* OverlappedComp, AActor* OtherActor, UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult);
};

.cpp

ADrop::ADrop()
{
	grabBox = CreateDefaultSubobject<USphereComponent>(TEXT("Grab collision"));
	grabBox->SetSphereRadius(200.0f);
	grabBox->bGenerateOverlapEvents = true;
	grabBox->OnComponentBeginOverlap.AddDynamic(this, &ADrop::OnOverlapBegin);
}

void ADrop::OnOverlapBegin(UPrimitiveComponent* OverlappedComp, AActor* OtherActor, UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult)
{
	// ...
}

AddDynamic seems to be working but OnOverlapBegin() will never be called. Are there any other properties I may be missing?

2

Have you created your Blueprint before implementing the overlap event?
If yes, you have to re-create your Blueprint for some reason: OnComponentBeginOverlap not working - World Creation - Epic Developer Community Forums

3

I bind my overlap event delegates this way and it works flawlessly

ADrop::ADrop()
 {
	grabBox = CreateDefaultSubobject<USphereComponent>(TEXT("Grab collision"));
	grabBox->SetSphereRadius(200.0f);
	grabBox->bGenerateOverlapEvents = true;
	
    FScriptDelegate BeginOverlapDelegate;
    BeginOverlapDelegate.BindUFunction(this, FName("OnOverlapBegin"));
    grabBox->OnComponentBeginOverlap.AddUnique(BeginOverlapDelegate);
 }
 
 void ADrop::OnOverlapBegin(UPrimitiveComponent* OverlappedComp, AActor* OtherActor, UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult& SweepResult)
 {
    GEngine->AddOnScreenDebugMessage(-1, 5.0f, FColor::Cyan, TEXT("PAAAAW OVERLAP"));
 }

Remember to add UFUNCTION() macro to OnOverlapBegin method.