BeginPlay() for UObject

Development Programming & Scripting C++
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1

I have a custom object which needs to be automatically initialised before it’s owning Actor invokes BeginPlay(), Here’s what I’ve tried so far based on this question:

MyActor:

AMyActor::AMyActor() {
    MyObj = CreateDefaultSubobject<UMyObject>(TEXT("MyObj"));
}

void AMyActor::BeginPlay() {
    Super::BeginPlay();

    if (MyObj) {
        MyObj->DoSomething();
    }

MyObject:

void UMyObject::DoSomething() {
    if (ActorOwner) {
      // ... Do something with ActorOwner
    }
}

void UMyObject::PostLoad() {
    Super::PostLoad();

    if (GIsEditor && !GIsPlayInEditorWorld) {
        return;
    }

    Init(GetOuter());  // ActorOwner = Cast<AActor>(GetOuter());
}

My main goal here is to avoid having to use MyObj->Init(this) inside the MyActor and instead the let object initialise itself since it becomes tedious when there are several custom objects

Am I doing this right or is there a better way?

2

No, there’s no particularly good hook for this with UObjects. Init functions are the most common practice.

One alternative would be for your object to be a UActorComponent instead of UObject. Those do include additional hooks into the Actor lifetime so that you could do things prior to BeginPlay.

3

you can use
virtual void PostInitProperties() override;

but its not a great solution

4

I tried that but it doesn’t work as intended

When I store the GetOuter() in PostInitProperties() and then use it in DoSomething() it shows as null value for some reason

void UMyObject::PostInitProperties() {
    Super::PostInitProperties();

    if (GIsEditor && !GIsPlayInEditorWorld) {
        return;
    }

    Init(GetOuter());  // ActorOwner = Cast<AActor>(GetOuter());
}

void UMyObject::DoSomething() {
    ActorOwner // This is null/invalid for some reason
}
5

I have several UObjects and I don’t think it would make sense for them to be UActorComponent

Is there really no other way?

6

whats the problem with all the custom objects having a parent class with an overridable Init()?

7

There’s no problem with it
The problem is the need to repeatedly call Init() instead of it being taken care of internally

8

just wrap it in a static

9

I don’t follow what do you mean by wrapping it in static?

10

i mean create a static function that creates and initializes your Object,