How to add an ActorComponent dynamically?

Development Programming & Scripting C++
1

I’m making a system where I add different components to a building depending on the values I pass to it. I can’t figure out how to add these components and get them back when I need to reference them.

2

You could write a function that takes a pointer to the AActor you want to attach to, a UClass pointer for the component class you want attached to the actor, and an FString for the name you want to name the component. Something like:


UActorComponent* AttachComponentToActor(AActor* TheActor, UClass* TheComponent, const FString& ComponentName);

When you pass the component class to this function, it’ll be something like this:


UClassOfComponentYouWantToAttach::StaticClass()

Now, inside of this function, to make the component:


UActorComponent* NewComponent = NewObject<UActorComponent>(TheActor, TheComponent, FName(*ComponentName));

Then you can attach it to the actor, and return it as a UActorComponent* so you have a reference to it you can use later.

3

One more thing, if you want some idea of how you can attach it to the actor after creation, checkout SSCEditor::AddNewComponent from SSCEditor.cpp – you can do some similar code to what this function does.

4

You should not use the Blueprint functionality for creating an Actor Component at runtime. The correct way to create one is this:



UActorComponent* NewComponent = NewObject<UActorComponent>(TheActor, ComponentClass, NAME_None, RF_Transient);
check(NewComponent);

NewComponent->RegisterComponent();

If you do not register the component properly, numerous features will not work correctly.

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