How to write my own application derived from UdpBasicApp in Omnet++ (inet)? - omnet++

Question

I want to derive a class from UdpBasicApp of inet in Oment++. Indeed, I want to write my own application. I wrote the following code, but when I compile the project, I have an error. For compiling this project without any error, what should I do?
Creating executable: out/clang-release//Manet_1.1.exe
out/clang-release//MyApp.o:(.rdata[_ZTIN4inet11UdpBasicAppE]+0x10): undefined reference to `typeinfo for inet::ApplicationBase'
out/clang-release//MyApp.o:(.rdata[_ZTV5MyApp]+0x640): undefined reference to `non-virtual thunk to inet::OperationalBase::handleOperationStage(inet::LifecycleOperation*, int, inet::IDoneCallback*)'
clang++.exe: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [Makefile:101: out/clang-release//Manet_1.1.exe] Error 1
MyApp.h
#include "../../inet/src/inet/applications/udpapp/UdpBasicApp.h"
using namespace inet;
class MyApp : public UdpBasicApp
{
public:
};
MyApp.c
#include "MyApp.h"
Define_Module(MyApp);
MyApp.net
import inet.applications.udpapp.UdpBasicApp;
simple MyApp extends UdpBasicApp
{
#class(MyApp);
}

Answer 1

Clearly you are working in your own project which does NOT properly link with the INET model. You MUST select INET as a project reference in your own project's project properties dialog. That will add INET's include folder to the include path, so you would need to (properly) write only
#include "inet/applications/udpapp/UdpBasicApp.h"
instead of
#include "../../inet/src/inet/applications/udpapp/UdpBasicApp.h"
And the linker command line would be also modified to link with the INET shared library properly.