event notifications not received as described - c++

Question

Problem:
Event notifications (From COM object - Server) are not received as listed in the Sink (class) implementation.
One event notification is received (Event_one), however, others are not received accordingly
If order is changed - in IDispatch::Invoke, that is:
if Event_one is swapped to Event_two then Event_two notification received but Event_one and others neglected accordingly
Question:
Better way to implement, IDispatch::Invoke or QI?
Using the wrong logic or approach?
Note:
No MFC
No ATL
Pure C++
using message loop: GetMessage()
STA model ( Coinitialize() )
Call to IDispatch::Advise successful (HRESULT from call S_OK)
After above, COM object method calls as normal (with interface pointer)
Single call to Advise
Type library generated from MIDL compiler
For instance (example):
Illustration of IDispatch::Invoke - taken from Sink Class:
HRESULT STDMETHODCALLTYPE Invoke(
{
//omitted parameters
// The riid parameter is always supposed to be IID_NULL
if (riid != IID_NULL)
return DISP_E_UNKNOWNINTERFACE;
if (pDispParams) //DISPID dispIdMember
{
switch (dispIdMember) {
case 1:
return Event_one();
case 2:
return Event_two();
case 3:
return Event_three();
default:
return E_NOTIMPL;
}
}
return E_NOTIMPL;
}
Illustration of QueryInterface:
STDMETHOD (QueryInterface)(
//omitted parameters
{
if (iid == IID_IUnknown || iid == __uuidof(IEvents))
{
*ppvObject = (IEvents *)this;
} else {
*ppvObject = NULL;
return E_NOINTERFACE;
}
m_dwRefCount++;
return S_OK;
};

Answer 1

Since you are receiving the notification for first method of the sink interface, I suspect, events are not sent on other methods from Server. If you have code of the server, just check the connection point class which throws the notifications.
You can also put a breakpoint in Invoke method of client application to check what are all the events it is receiving.

Answer 2

SOLVED:
After reviewing the corresponding IDL FILE (generated by the MIDL compiler), it was evident that each method contained in the IEvent interface, has a unique ID. For instance, Event_one has an ID of 2. For example:
methods:
[id(0x00000002)]
HRESULT Event_one();
Therefore, making a change as followings - in the IDispatch::invoke implementation (illustrated in the above question):
//omitted
if (pDispParams) //DISPID dispIdMember
{
switch (dispIdMember) {
case 2:
return Event_one();
//omitted
Now when invoked accordingly, the desired/correct method is now executed.