In case of failure to using fl_xid();

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I did try apply DirectX input to using joystick for my HID emulation, but my testing program failure in SetCooperativeLevel() API on dinput. At the result of analyse, I found FLTK API fl_xid() returns wrong HWND value from debuger.

inspection01 Just inspected real HWND(handle of window) value with Process Hacker. It was something wrong in internal value of calling fl_xid(); like below image.



To verify in presumption of fact, I did compare with my FLTK DX8 joystick example, and it has exactly right HWND value in calling fl_xid();. Difference is only multi window in one program. Is it a cause of wrong HWND?


Whatever is reason, I need change my code to getting HWND in source code.

    //HWND hCurWin = fl_xid( winMain );
    HWND hCurWin = GetWinHandle( GetCurrentProcessId() );

It was just simple, and GetWinHandle() is following.

HWND GetWinHandle(ULONG pid)
    HWND hTmp = FindWindow( NULL, NULL );

    while( hTmp != NULL )
        if( GetParent(hTmp) == NULL )
            if( pid == ProcIDFromWnd( hTmp ) )
                return hTmp;

        hTmp = GetWindow( hTmp, GW_HWNDNEXT );
    return NULL;

I don’t have time to know what’s wrong in fl_xid(), but it will be good solution to using DirectX devices in FLTK windows program.