Debugmessage nullpointer?!

Hello UE community,

i use this line in a method of a created Actor class, without it, everything works.

GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, TEXT("..."));

And I get this exception

Unhandled exception at 0x00007FFD5A87F5E4 (UE4Editor-Engine.dll) in UE4Editor.exe: 0xC0000005: Access violation reading location 0x0000000000000778.

The compiling stop at the if command from UnrealEngine.cpp

/** Wrapper from int32 to uint64 */
void UEngine::AddOnScreenDebugMessage(int32 Key, float TimeToDisplay, FColor DisplayColor, const FString& DebugMessage)
	if (bEnableOnScreenDebugMessages == true)
		AddOnScreenDebugMessage( (uint64)Key, TimeToDisplay, DisplayColor, DebugMessage);

What I’m doing wrong?


You need to have UE_BUILD_DEBUG as your build type for that line to work and

     GEngine->AddOnScreenDebugMessage(-1, 2.0f, FColor::Red, "Some Message");

would be the proper way

Generally messages to the screen are printed something like this

 UE_LOG(MyGame, Log, TEXT("Some Messsage") );

I highly reccomend reading Ramas post about debugging and printing messages here

Hope this helps
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