Array of UObject ptrs(e.g. UActorComponent)

Development Programming & Scripting
1

Hi there,

I’m a newbie to UE4, so my question is, how to handle a set of components in an actor (not define them one by one manually) , with CORRECT GC behavior.

I’ve tried as below, but crashed when dynamically adding new component into it …

class AFoo : public AActor
{
public:
...
TArray<UTextRenderComponent*> testArray;
...
}

And as far as i know, UTextRenderComponent* testArray[10]; is not correct either.

Any reply or advice appreciated!

2

On your header you need to declare your array like this

UPROPERTY()
TArray<UTextRenderComponent*> TextArray;

Now, to dynamically create a component at runtime:

UTextRenderComponent* NewText = NewObject<UTextRenderComponent>(this); 
// this reference to your Actor as Outer (necessary for GC)
NewText->RegisterComponent(); 
//You need to call it manually since you create this component at runtime

//Make what you want like set text, attach to component, etc..

TextArray.Add(NewText);

Also there is some built-in function to get an Array of UActorComponent from your actor, maybe better in some case :slight_smile:

3

Sorry for the late reply, I’ve tested that and it works well, THX!

btw, u mentioned that
“there is some built-in function to get an Array of UActorComponent from your actor, maybe better in some case”,
do u mean by “using GetCompoentXXX() functions to find those components when needed” a better way than “saving them in an separate member array”?(better efficiency? better robustness? or some other advantages?)

Much apprieciated!

4

Yeah using GetComponentsByClass will give you all registered components of this class and avoid you to manage manually your TextArray. Both are good :slight_smile:

5

got it. thx~~