[icp-slam.cpp] Get the auto-generated window handle

Hi, I am trying to modify icp-slam.cpp.

In icp-slam.cpp, "MapBuilding_ICP" function creates a window automatically to build map.

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        win3D = CDisplayWindow3D::Create("ICP-SLAM @ MRPT C++ Library", 600, 500);   <----------------------
        win3D->setCameraZoom(20);
        win3D->setCameraAzimuthDeg(-45);
              ..................

==========================================

When user closes the window, the application remains on the background.

This causes problem in my application.

I know how to use Windows API to get the window handle,

but I would like to know how to get the "window handle or window destruction message" by using member functions of win3D.

Is there a way to do so?

Thanks a lot.