How to override C++ function in Blueprint?

Development Programming & Scripting
1

There is some function, which I gonna to override in Blueprint

.h file:

UFUNCTION(BlueprintCallable, Category = RemoteServer)
virtual void ServerMsg(const FString& msg);

.cpp file:

void UCrazyRacingGameInstance::ServerMsg(const FString& msg)
{
 	PRINT("Server message: %s", *msg);
}

This function will be called by CallFunctionByNameWithArguments method and using BlueprintNativeEvent is improperly.

If I try to define ServerMsg function in blueprint, I got the message:

Error: The function name in node Server Msg is already used
Error: Cannot override '::ServerMsg' at Server Msg which declarated in a parent with a different signature!

How to override this function? Help me please :slight_smile:

alt text

2

I’m afraid that you can’t declare UFUNCTIONs as virtual. At least that’s what I can tell by experience.

3

But compiled successfully. virtual or not virtual it makes no difference.

4

You can declare UFUNCTION() functions as virtual. However you can not override them inside blueprints. Only inside other C++ classes. You probably already seen that you can not see the function you declared virtual, inside blueprint editors overridable functions list.

If you want to override a function inside blueprints, you will need to use BlueprintNativeEvent or BlueprintImplementableEvent as UFUNCTION() specifiers.

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5

But method CallFunctionByNameWithArguments is not applicable to Events.
Are there analogs of this method? Or this method may be used too?

Just I don’t want to increase function count in C++ code for one action.

6

I am not familiar with that function and it seems DOC has very little information.

Instead of function can you tell what you are trying to do? Maybe i can suggest some other approach.

7

I use my server for remote function calling CLIENT <–> SERVER
At case CLIENT → SERVER call I just use defined method name in C++ and place the string with the method and parameters to CallFunctionByNameWithArguments for implicit call.
But in future I think realisation can be moved also in blueprints for more extensibility.

8

As far as i understand, you are trying to call a function ?server has access to? from client computer. I am not experienced with networking so i cannot be of much help.

Maybe by using replication you can achieve the same effect or you can post another question regarding possible different approaches to this.

9

This is not UE4 server. This is remote manager for some controls.

Problem soloved. Events also can be called too by CallFunctionByNameWithArguments. Thank you for attention :slight_smile:

10

FindFunction and ProcessEvent is nice things too:)

11

does not work
does the function need to be virtual ?

12

Not really, just having UFUNCTION(BlueprintImplementableEvent) would work.

Try sharing what error are you getting.

13

In case anyone else is looking:

Header File:

UFUNCTION(BlueprintCallable, BlueprintNativeEvent, Category = "CPP Overridable", meta = (ForceAsFunction))
void MyCPPFunc(int InParam, TArray<FVector>& OutArray);

CPP File:

void MyCPPFunc_Implementation(int InParam, TArray<FVector>& OutArray)
{
  //some logic
}
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