Template UClass or an other way ?

Development Programming & Scripting C++
1

Hello dev, i would like to make something like that :


template <class T>
UCLASS()
class PROJECT_API AMyActor : public AActor
{
    GENERATED_BODY()

public:
    AMyActor();

    UPROPERTY(EditDefaultsOnly)
    T* MyComponent = nullptr;
}

AMyActor<T>::AMyActor()
{
    MyComponent = CreateDefaultSubobject<T>("MyComp");
}

UCLASS()
class PROJECT_API AMyChildActor : public AMyActor<USceneComponent>
{
    GENERATED_BODY()
}

obviously, he doesn’t compile. But, my questions :

Can we have template UClass ? If yes, how please ?
Did you see a design pattern for make something like that or a tips ?

Thank’s for the read,
Have a nice day !

1 Like
2

No, you can’t use templates with reflection or UObjects.

There are a handful of special templated containers in UE4 that support reflection such as TArray, TMap and TSet etc, but they all have special handling.

3

Ok thank’s :slight_smile:

4

I have something, but for this moment we can’t edit component in editor, but it’s work.


class UMyGenericClass
{
public:
    UMyGenericClass()
    {}

    UMyGenericClass(AActor* _actor)
    {}
};

template<class T>
class UMyTemplateClass : public UMyGenericClass
{
public:
    UMyTemplateClass(AActor* _actor)
        : UMyGenericClass() 
    {
        if (_actor)
        {
            MyComponent = _actor->CreateDefaultSubobject<T>("MyComp");
        }
    }

public:
    T* MyComponent = nullptr;
};

template<class T>
struct STag { using type=T; };

UCLASS()
class USETEMPLATE_API AMother : public AActor
{
    GENERATED_BODY()

public:    
    // Sets default values for this actor's properties
    AMother();
    template<class T>
    AMother(STag<T> _tag);

public:
    UMyGenericClass GenericClass;
};

template<class T>
AMother::AMother(STag<T> _tag)
{
    GenericClass = UMyTemplateClass<T>(this);
    PrimaryActorTick.bCanEverTick = true;
}

and in my .cpp


// Sets default values
AMother::AMother()
    : AMother(STag<USceneComponent>{})
{
}

if you have any question, you can mp me