Re: Pass object from worker thread to main thread

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"David Wilkinson" <no-reply@xxxxxxxxxxxx> wrote in message
news:O9xdrma1FHA.3720@xxxxxxxxxxxxxxxxxxxxxxx
> Inline:
>
> Steve wrote:
>
>> "David Wilkinson" <no-reply@xxxxxxxxxxxx> wrote in message
>> news:%23TyRcBa1FHA.1740@xxxxxxxxxxxxxxxxxxxxxxx
>>
>>>Steve:
>>>
>>>You can make a pointer of it and put it in the wParam or lParam (and cast
>>>it back in the receiving function). But you need to think very carefully
>>>about object lifetimes when you do this (the thread function keeps on
>>>running after it does the PostMessage()).
>>
>>
>> Can I not return a copy of new_patient to the dialog class and work with
>> that?
>
> Yes, but you have to return a pointer, because wParam or lParam are not
> large enough to hold a general object. And you have to return a pointer
> that will not do out of scope. Something like:
>
> WPARAP wParam = (WPARAM) new
> Patient(pDlg->getManager().GetNextPatient());

Big help this example. :)

> [There's a lot of (unnecessary?) object copying going on here]

Yes, it is unnecessary. I'm too new to C++ (and used to Java) to produce
efficient code.


.

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