TryLoadClass returns null

Development Programming & Scripting
,
1

Hi,

My goal is to show a popup on top of everything when a disconnection occurs.
I was able to successfully do it with Unreal 4.27. Now, I need to make it happen on the version 4.12.

I changed FSoftClassPath to FStringClassReference basically and tried to call the TryLoadClass method of it.
In version 4.12, it returns a null.
I tried to step in the engine code and it seems it is unable to create a linker.

Here is the code to show the popup. This exact code works (runs and show the popup) with 4.27 and compiles on both 4.12 and 4.27.

void FClassNamePluginModule::TryShowConnectionLostPopup()
{
    if (!m_showConnectionLostPopup)
        return;

    UGameInstance* gameInstance = nullptr;
    TArray<APlayerController*> playerList;
    GEngine->GetAllLocalPlayerControllers(playerList);
    if (playerList.Num() > 0)
    {
        gameInstance = playerList[0]->GetGameInstance();
    }
    else if(GEngine->GetWorld() != nullptr)
    {
        gameInstance = GEngine->GetWorld()->GetGameInstance();
    }
    if (gameInstance == nullptr)
        return;

    FString path(L"WidgetBlueprint'/PluginName/Blueprints/UBP_WidgetNotification.UBP_WidgetNotification_C'");
#if ENGINE_MAJOR_VERSION >= 4 && ENGINE_MINOR_VERSION < 15
    FStringClassReference notificationClasstRef(path);
#else
    FSoftClassPath notificationClasstRef(path);
#endif

    UClass* notificationClass = notificationClasstRef.TryLoadClass<UUserWidget>();
    if (notificationClass)
    {
        FMessageDialog::Open(EAppMsgType::Ok, LOCTEXT("ThirdPartyLibraryError3", "DC 3"));
        UUserWidget* notificationWidget = CreateWidget<UUserWidget>(gameInstance, notificationClass);
        if (notificationWidget)
        {
            FMessageDialog::Open(EAppMsgType::Ok, LOCTEXT("ThirdPartyLibraryError4", "DC 4"));
            notificationWidget->AddToViewport();
            m_showConnectionLostPopup = false;
        }
    }
}

Would you have any idea what I am doing wrong? Also, I checked the the notificationClasstRef variable is NOT null and Valid (called the method IsValid())

Thank you