[Oorexx-devel] CSelf and mixin classes

[Mark M. <mie...@gm...>]

I'm a little confused about how CSelf will work with mixin classes.

(Right now I'm just using structs for the CSelf, in the future I
intend to move to C++ classes.)  Take this abbreviated example from
ooDialog which uses mixin classes a lot.

::class 'WindowBase' public mixinclass object

::method init_windowBase external "LIBRARY oodialog wb_init_windowBase"
::attribute hwnd get external "LIBRARY oodialog wb_getHwnd"

::class 'PlainBaseDialog' public inherit WindowBase ResourceUtils

::class 'DialogControl' public inherit WindowBase WindowExtensions

Since CSelf gets set as an object variable and since an object
variable in WindowBase is not seen by DialogControl, (or
PlainBaseDialog,) I though I would need separate CSelf structs for
WindowBase and say DialogControl.

So, the C++ code for an API implementation of init_WindowBase() looks
something like this:

RexxMethod1(logical_t, wb_init_windowBase, OSELF, self)
{
    dbgPrintClassID(context, self);

    RexxBufferObject obj = context->NewBuffer(sizeof(CWindowBase));
    pCWindowBase pcs = (pCWindowBase)context->BufferData(obj);
    // initialization ...
    context->SetObjectVariable("CSELF", obj);
    return 0;
}

My dbgPrint  shows:
Class: TestDialog

When I sort of thought it would be WindowBase.  TestDialog is actually
a subclass of PlainBaseDialog.

If I now go to set a different struct in DialogControl::init():

RexxMethod2(uint32_t, dlgctrl_init, OPTIONAL_POINTER, args, OSELF, self)
{
    RexxBufferObject cdcBuf = c->NewBuffer(sizeof(CDialogControl));
    // initialziation, etc.
    context->SetObjectVariable("CSELF", cdcBuf);
    // ...
}

My WindowBase code no longer works, for example:

RexxMethod1(RexxStringObject, wb_getHwnd, CSELF, pCSelf)
{
    return pointer2string(context, ((pCWindowBase)pCSelf)->hwnd);
}

Remember, wb_getHwnd is mapped to WindowBase::hwnd().  But pCSelf
seems to now be  a pointer to a CDialogControl struct, rather than a
pointer to a CWindowBase struct.

Is this perhaps a bug, or am I more than usually confused?

--
Mark Miesfeld