OpenEuphoria

Re: EuCOM - Passing an object to another object

• Posted by Jonas Temple <jtemple at yhti.net> Apr 04, 2006
• 783 views

Matt Lewis wrote:
> You should probably use get_obj_this().  When you pass a EuCOM handle, it
> will return the actual pointer to the object.  get_obj_from_this() goes
> the other way.  The parameter type should be either VT_DISPATCH or 
> VT_UNKNOWN.

Well at least I was on the right track...

I tried the get_obj_from_this() with type VT_DISPATCH and VT_UNKNOWN.  On one of
the invoke() calls I get a machine exception from call_stdcall_proc().

Here's the interface definition from the include created by tbrowse:

-- disp methods for AutScreenReco
global constant
AutScreenReco_m_AddPS = 1610743808,
    -- Add a PS object to monitor to the autScreenReco Object
    -- Returns:  VT_VOID
    -- AutPS VT_DISPATCH [IN]
AutScreenReco_m_IsMatch = 1610743812,
    -- Compare a given PS to a given Screen Description
    -- Returns:  VT_VOID
    -- AutPS VT_DISPATCH [IN]
    -- ScreenDescription AutScreenDesc [IN]
AutScreenReco_m_RegisterScreen = 1610743810,
    -- Register the Screen Description with the Screen Recognition 
    --  Object
    -- Returns:  VT_VOID
    -- ScreenDescription AutScreenDesc [IN]
AutScreenReco_m_RemovePS = 1610743809,
    -- Remove a PS object from the autScreenReco Object
    -- Returns:  VT_VOID
    -- AutPS VT_DISPATCH [IN]
AutScreenReco_m_UnregisterScreen = 1610743811
    -- Unregister a Screen Description from the Screen Recognition 
    --  Object
    -- Returns:  VT_VOID
    -- ScreenDescription AutScreenDesc [IN]

the error is happening on the m_RegisterScreen method.  The call to m_AddPS
works file and as you can see, the AutPS object is defined the VT_DISPATCH. 
However in m_RegisterScreen the "RegisterScreen" object is defined as
AutScreenDesc, not VT_DISPATCH or VT_UNKNOWN.

What's the difference between the two?

Thanks!


Jonas Temple
http://www.yhti.net/~jktemple