C++ call parent-constructor manually?

Development Programming & Scripting C++
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1

I would like to have full control over when the parent-constructor is called (it seems that UE4 calls it automatically and before the child-constructor). I have a piece of code in BaseEnemy (that inherits from BaseCharacter) that must be performed in the constructor, but before the BaseCharacter-constructor runs.

ABaseEnemy::ABaseEnemy()
{
  // <My code that must be performed before the base-constructor here>

  // Call super constructor <<<<<<<<< this is not possible?

  // The rest of my awesome code.
}
2

Hi,

It is impossible to do what you are trying to do. The only way to do it is with multiple bases, but UE4 requires that the UObject base is listed first:

// illegal - UnrealHeaderTool will reject this
UCLASS()
class ABaseEnemy
    : public ClassWhoseConstructorMustExecuteBeforeAActorsConstructor
    , public AActor
{
};

Steve

1 Like
3

More than that this is a general and 101 C++ spec !!
http://www.learncpp.com/cpp-tutorial/113-order-of-construction-of-derived-classes/

4

Oh I see. I’m still too used to using C#.

5

You can’t do that in C# either.

6

Then it must have been Javascript or Ruby because I’m sure I used it before in another language not long ago. But indeed both C++ and C# won’t allow it.

7

C++ allows multiple inheritance, it’s just Unreal that doesn’t. As soon as you put UCLASS() at the top of a class, you’ve got to follow Unreal’s rules.