Why isn't IID_ITaskbarList3 defined?

[Nieto]

On Monday, 16 October 2017 at 05:06:26 UTC, evilrat wrote:
> On Sunday, 15 October 2017 at 15:13:09 UTC, Nieto wrote:
>> I'm trying to write a blinding and I found both 
>> IID_ITaskbarList and IID_ITaskbarList2 are defined but 
>> IID_ITaskbarList3 isn't. Any reason why it isn't defined? 
>> sorry if it sounds such a naive question, I'm new to COM and D 
>> interop. I knew a thing or two about PInvokes with C#.
>>
>> Then how do I define it myself?
>>
>> I've tried this:
>>
>>> GUID IID_ITaskbarList3 = 
>>> createGUIDFromString("{ea1afb91-9e28-4b86-90e9-9e9f8a5eefaf}");
>>
>>> GUID createGUIDFromString(string guidStr) {
>>>		GUID guid;
>>>		wchar* GUID_STR = toUTFz!(wchar*)(guidStr);
>>>		HRESULT hr = IIDFromString(GUID_STR, &guid);
>>>		assert(SUCCEEDED(hr));
>>>		return guid;
>>>	}
>>
>> I'm unsure if it's the proper way to do it (if not, please 
>> show me the right one)
>>
>> But the call to CoCreateInstance() still fails to access any 
>> member of m_pITaskBarList3 object, so I'm making sure I'm 
>> passing the correct arguments to the function. The memory 
>> access error is:
>>
>>> object.Error@(0): Access Violation
>>
>>
>>
>>> HRESULT hr = CoCreateInstance(&CLSID_TaskbarList, null, 
>>> CLSCTX_INPROC_SERVER, &IID_ITaskbarList3,
>>> cast(void **)   &m_pITaskBarList3);
>>> assert(hr == S_OK);
>>
>> The assert() doesn't run, so the error is somewhere else... I 
>> guess.
>
> Did you call CoInitialize before creating anything? Is your 
> ITaskbarList3 defined as interface?
>
> Here is the simple example anyway
> https://gist.github.com/Superbelko/277d86a17d497eae85a7f1788bfd83b4
>
>
>
> There are no predefined GUID's and declarations for some stuff 
> because standard WinAPI bindings is incomplete, you can 
> probably contribute and add some
> https://github.com/dlang/druntime

Yes, I did call CoInitialize(null) before call CoCreateInstance().
I thoguht the GUID was some kind of constant value to identify 
the ITaskbarList3 (the struct name is even IID). I was dead wrong 
lol but I was just starting with the COM world. I defined 
CLSID_ITaskbarList3 like your IID_ITaskbarList3. I realized my 
mistake: out of C++ habit, I declared the ITaskbarList3 as a 
pointer! That's why it wasn't working. I didn't realized it until 
I read your code. Again, thank you very much. I'll try contibute 
to the WinAPI binding once mine is complete.

Have a nice day! :)