You should manually add OnPickedUp_Implementation() function in your .cpp file of Pickup class. Just like this:
void APickup::OnPickedUp_Implementation()
{
...
}
I have not seen the tutorial series you’re talking about so i can’t really tell you what should be inside the function. But i guess it was meant to be overridden in Blueprint, so it should be an empty function, if nothing had to be done in base class.
That’s the way server rpc are usually defined, but since 4.7 the same code that used to work now generates those warnings.
I don’t understand the warning, but i am a c++ baby, so maybe it means something clear.
Don’t have 4.7, but that warning seems pretty clear: It’s telling you to declare OnPickedUp_Implementation yourself because the UnrealHeaderTool will no longer do it come next version. The fix would be to declare both functions: