Reparenting Blueprint class to C++ parent does not show details for inherited components

Development Programming & Scripting Blueprint
, , , , ,
1

I started my project with a Blueprint-heavy inheritance hierarchy and eventually moved many of the base classes to C++. However, when reparenting the Blueprint classes to the C+±backed classes, the inherited components defined in C++ do not show anything in their Details panel in the Blueprint subclass.

Reproduction steps:

  1. Create a BP-only inheritance tree. For example:

    MyClass_BP
    ├── MyChild0_BP
    | └── MyChild0_Child0_BP
    └── MyChild1_BP

  2. Add some ActorComponents to MyClass_BP and notice they show up correctly in the MyChild subclasses. Add some script references to the inherited actors and notice they behave as expected.

  3. Create a C++ class, we’ll call it AMyClass

    UCLASS(Blueprintable, BlueprintType)
    class AMyClass : public AActor
    {
    GENERATED_BODY()

    UPROPERTY(BlueprintReadWrite, Category="Components", EditAnywhere)
UCameraComponent* CameraComponent;

    }

  4. Reparent MyClass_BP to inherit from AMyClass.

  5. Open MyClass_BP and select the inherited CameraComponent

  6. Notice the CameraComponent’s Details inspector is empty or is missing properties for the component.

  7. Notice that the scripts that consume the CameraComponent see it as “None”

Expected Results:
Components inherited from C++ classes and properly constructed using CreateDefaultSubobject in the C++ class’s constructor should display their Details, should not be None in scripts, and should behave exactly the same as other components when reparenting BP classes.

Actual Results:
Inherited components that come from a C++ base do not show their Details in the inspector window and are None in scripts after reparenting an existing BP class to the C++ base.

Reproducibility:
Even after recompiles, restarts, and other tactics to clear build data, this issue persists. This appears to be a common issue, but is not consistent.

Severity:
Severe. Anyone attempting to refactor their project to take advantage of a C++ base class will have their entire BP hierarchy DESTROYED by this bug.

2

Hello,

We’ve recently made a switch to a new bug reporting method using a more structured form. Please visit the link below for more details and report the issue using the new Bug Submission Form. Feel free to continue to use this thread for community discussion around the issue.

https://epicsupport.force.com/unrealengine/s/

Thanks

3

Have you tried to add meta=(AllowPrivateAccess = "true") to the UPROPERTY macro since you declared it as a private variable?

private:
UPROPERTY(
Category="Components"
, EditAnywhere
, BlueprintReadWrite
, meta=(AllowPrivateAccess = "true"))
UCameraComponent* CameraComponent;