MFC Custom Control in a regular MFC DLL

Ah ok thanks... what about loading the class I pasted in the code from the main .CPP so it would be loaded in the Toolbox?....

I've never tried creating an ActiveX control that integrates with the VS Toolbox.  

Just loading code int one or another cpp file is not likely to fix anything.  The object needs to get instantiated at some point.  But I don't know when or how that needs to be done.  And 125 points is small incentive for me to try a test project.

Hello Dan,

I've been playing with it in these two days and I figured out to have a custom control in the Toolbox it has to be an OCX ActiveX COM.
So I played with a Regular DLL thinking on substituting a CStatic in test application as like I have a virtual rect where to put my control.
So I changed the Create method in the class with:

BOOL CaChart::Create(const CRect& rect, CWnd* wnd)
{
    if (!CWnd::Create(CACHART_CLASSNAME, _T(""), WS_VISIBLE, rect, wnd, wnd->GetDlgCtrlID()))
        return FALSE;
    SetWindowPos(wnd, 0, 0, 0, 0, SWP_NOMOVE|SWP_NOSIZE);
    return TRUE;
}

and in the test MFC application I added a CStatic in the resource and I coded this:

CStatic* c_CStaticPlaced = (CStatic *)GetDlgItem(IDC_MYSTATIC);
CRect r;
c_CStaticPlaced->GetWindowRect(&r);
ScreenToClient(&r);
CCaChart* c_MyControl = new CCaChart();
CWnd* pWnd = c_CStaticPlaced->GetDlgItem(c_CStaticPlaced->GetDlgCtrlID
());
c_MyControl->Create(r, pWnd);
c_CStaticPlaced->DestroyWindow();

but I get a linker error:

1>test_chartDlg.obj : error LNK2019: unresolved external symbol
"public: __thiscall CCaChart::CCaChart(void)" (??0CCaChart@@QAE@XZ)
referenced in function "protected: virtual int __thiscall
Ctest_chartDlg::OnInitDialog(void)" (?
OnInitDialog@Ctest_chartDlg@@MAEHXZ)

So since constructor and destructor are declared as like the class wizard did as PUBLIC  I wonder why it would return me this kind of error....

I added in the linker properties the path and the name of the .lib file as MSDN said but I'm stuck with this weird linker error... do you have maybe a suggest?...

Thanks
Ciao,
Luigi

That's because you have #include'd the right header file (probably CaChart.h) but the CPP file is not part of the project.  The compiler cannot find any code that will constuct the CCaChart  object.

If you have an OCX, then you need to have the ClassWizard create a wrapper for it so that there is some code to run when you construct the object, or when you use any of its mmber functions, etc.

HI Dan,

it was nothing about that,... .just I forgot to export methods and stuffs from the class so I could use them in the application so I added something like:

#ifdef MYDLL_BUILD
#define MYDLL_IO _declspect(dllexport)
#else
#define MYDLL_IO _declspec(dllimport)
#endif

class MYDLL_IO MyDLL : public CWnd...

and I already reached to draw something on the device context through the OnPaint and OnDraw events.
But if I create a creation own-function (because I have to pass some initialization parameters) to just initialize the dc because it's the background which has to be fixed. And in this case it doesn't draw anything even if I create an instance of CMemDC...maybe when I try to draw something on DC outside OnPaint structure I have to use a different method?...

Nevermind, I figured out everything.... I just had to code an OnPaint() event which calls an OnDraw() event so I had also to set a BOOL variable to stop drawing when resizing so I can manage my own OnEnterSizeMove/OnExitSizeMove plus Invalidate()/UpdateWindow(). On the other hand, in the OnDraw I added a grid and managed it with a OnTimer which would redraw the grid every second (or whatever time interval wanted) having an offset with an Invalidate().

Now I can implement the rest of the component (ah BTW, I had to switch from static library to shared library due for warnings I get, on the other hand from start question about #1 I figured I can't load a DLL in the toolbox because it has to be a COM ActiveX, so I call the DLL component directly from the code and for #2 I assign points to DanRollins). thanks to everyone!  :-)))

Ciao,
Luigi