AttachToComponent not working at editor time

Development Programming & Scripting
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1

I’m implementing a preview of a spawner component.

AttachToComponent returns True, and preview actor Attaches as a child on the world outliner, but stays in place when the parent Actor is moved.

I think that something is needed more to do this at the editor level, but I’m not sure.

Also, the code to delete it when the ActorClass changes is not triggered because the PreviewActor is always nullptr. I don’t know why this is.

// .h
UPROPERTY(VisibleAnywhere, Category = "Spawner")
TWeakObjectPtr<class ASpawnerPreviewActor> PreviewActor; 

// .cpp
void USpawnerComponent::PostEditChangeProperty(struct FPropertyChangedEvent& PropertyChangedEvent)
{
	Super::PostEditChangeProperty(PropertyChangedEvent);

	const FName PropertyName = PropertyChangedEvent.GetPropertyName();
	if (PropertyName == GET_MEMBER_NAME_CHECKED(USpawnerComponent, ActorClass))
	{
		InitPreview();
	}
}

void USpawnerComponent::InitPreview()
{
	if (PreviewActor.IsValid())
	{
		PreviewActor->Destroy();
		PreviewActor.Reset;
	}



	...

	FActorSpawnParameters Params;
	Params.SpawnCollisionHandlingOverride = ESpawnActorCollisionHandlingMethod::AlwaysSpawn;

	if (ASpawnerPreviewActor* NewActor = World->SpawnActor<ASpawnerPreviewActor>(Params))
	{
		USceneComponent* PreviewRootComp = NewActor->GetRootComponent();
		// Register Root Component
		PreviewRootComp->RegisterComponent();
		
		NewActor->AttachToComponent(this, FAttachmentTransformRules::SnapToTargetIncludingScale);
		NewActor->OwnerSpawner = this;
		
		// Temp Actor for duplication
		AActor* TempActor = World->SpawnActor<AActor>(ActorClass);
		TempActor->RegisterAllComponents();

		// PrimitiveComponent Refs
		TArray<UPrimitiveComponent*> PrimitiveComps;
		TempActor->GetComponents(UPrimitiveComponent::StaticClass(), PrimitiveComps);

		// Duplication and register component
		for (UPrimitiveComponent* const& PrimitiveComp : PrimitiveComps)
		{
			UPrimitiveComponent* NewComp = DuplicateObject<UPrimitiveComponent>(PrimitiveComp, NewActor);
			NewActor->AddInstanceComponent(NewComp);
			NewActor->AddOwnedComponent(NewComp);
			NewComp->RegisterComponent();
			
			bool bSuccess = NewComp->AttachToComponent(PreviewRootComp, FAttachmentTransformRules::SnapToTargetIncludingScale);
			UE_LOG(FCSpawner, Warning, TEXT("AttachToComponent %s"), bSuccess ? TEXT("Succeed") : TEXT("failed"));
			
			NewComp->SetRelativeLocationAndRotation(PrimitiveComp->GetRelativeLocation(), PrimitiveComp->GetRelativeRotation());
		}
		
		// Destroy Temp Actor
		TempActor->Destroy();

		PreviewActor = NewActor;
	}
}