How to cast a child actor component to its original class from outside the parent actor?

[rcolaneri]

Hello!
Please I need a hand to understand what I am doing wrong and how to do this because I didn’t get it even reading other posts and watching some related videos.

I have an actor BP that is an elevator and it has another actor called Puerta (Door) as a component. I have been trying to access to that component from outside the BP using an interface but unsuccessfully. I can’t get to cast it.
I keep receiving a message saying: ‘BP Puerta Ascensor Ch’ does not inherit from ‘Scene Component’ ( Cast To BP_PuertaAscensorCh would always fail).

I’ve also tried the ‘Get Child Actor’ as I read in other posts but at that instance I don’t have that node available.

So how is the right way to make it?

This is the parent actor:

My blueprint from outside. There I am trying to read a variable of the child actor:

The attempt to get child actor when I found the desired object

[RecourseDesign]

Hi,
Cast it to a “ChildActorComponent”, then call GetChildActor.

[rcolaneri]

Ok! Done.
Now what do I do?

Because I still can’t cast the Actor “Puerta” from the child actor that I got, so I still have no acess to the public properties of the child.

[RecourseDesign]

Could you please share a snapshot of the Blueprint Editor with Puerta selected? and in the details panel , make it show the Class and Template part of the details.

You should be able to Cast that ChildActor to Puerta if everything in the template bit is correct.

[rcolaneri]

Sure, here is
The only weird thing I see there is the “-1” at the end of the template name but it doesn’t seem to be relevant. Could that be the reason why the cast to fails?
Maybe I need to destroy the actor and make it again from scratch

[RecourseDesign]

That looks ok - yes, the -1 fine. I just tried making the same routine here and it works perfectly - is this what you did and it fails?

[rcolaneri]

Pretty much. There are a few differences, maybe it’s something of that…

My comparison is not strict equaly and the blueprint is not placed in the constructor event but a custom event in the BP interface because I must handle it from outside the parent.

I am calling the event from a widget embedded in an object on the wall (the elevator call button called ‘ControlAscensorPB’ on the ground floor, 1st floor, etc.). And everything works perfect but that cast… honestly I am lost with this issue
As you said, it shoud work… but not. Cast fails all the time. No access to the child.

[RecourseDesign]

What happens if you PrintString the object it does have as a child?

[rcolaneri]

Ok I just printscreened the object and class… and the editor keeps adding weird thigs to the end. A “2021” in the name of the object and a “_C” in the class name I swear I didn’t add anything of that to the names. WTF is doing this editor? lol

[RecourseDesign]

Oh - that’s showing that the cast IS working - the _C is normal (class) and the 2021 is to ensure the name is unique in your scene.

So if that cast is working ok - perhaps it is finding multiple objects with that name, and failing to cast the other?

Maybe rather than loop through testing the name - you could add a “Tag” to the Component and then use “GetComponentsByTag” instead?

That would need to be plugged into the “Ascensor”.

[rcolaneri]

There is no other object with the name “Puerta” but I tried getting it by tag anyway. Same result the 2nd cast fails.

So there is no way to use actors as components? Should I put all actors directly to the maps?
If no choice then it would be a shame because I wanted to make a reusable full functional actor for all my maps. I’m an old school programmer so I like to reuse my classes haha. I expected this to be simpler.

Thanks anyway for the quick replies and all the help you are giving to me RecourseDesign, much appreciated sir!!

[RecourseDesign]

You’re welcome!

Maybe another way to do it is to create a function in Ascensor that you call from the Interface, that function could then directly use the ChildActor component (drag onto your blueprint) and call GetChild() then cast from there?

[rcolaneri]

Ok I did it as you suggested, I created an event in the actor ‘Ascensor’ and I handle the components from inside when I call it. And touché! At least now the cast works well when I push the button playing on the host (it’s a multiplayer game) but fails on the client. This could be probably caused by a replication wrongly set but it’s a big advance!!

Thank you sou much RD, you rock!!