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Yes, but when I write my class I still don't know the number of columns.<br />
That's why it is a template.
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Yes, but when I write my class I still don't know the number of columns.
That's why it is a template.

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I know - that is a Catch22, but that's the way it is...
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I know - that is a Catch22, but that's the way it is...

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So what you're saying is that it can't be done.<br />
A CWnd derived that is a template and also needs to map messages ?<br />
Can I somehow call the BEGIN_MESSAGE_MAP where I instatiate CMyClass ?
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So what you're saying is that it can't be done.
A CWnd derived that is a template and also needs to map messages ?
Can I somehow call the BEGIN_MESSAGE_MAP where I instatiate CMyClass ?

<div>
The BEGIN_MESSAGE_MAP macro is actually part of the instantiation of the class, not the declaration. You would need a separate BEGIN_MESSAGE_MAP section for every separate instantiation of the class.<br />
<br />
Just by using the BEGIN_MESSAGE_MAP macro you would be creating an instance of the class, that's why you would need to specify the number of columns as part of the macro.
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The BEGIN_MESSAGE_MAP macro is actually part of the instantiation of the class, not the declaration. You would need a separate BEGIN_MESSAGE_MAP section for every separate instantiation of the class.

Just by using the BEGIN_MESSAGE_MAP macro you would be creating an instance of the class, that's why you would need to specify the number of columns as part of the macro.

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<div class="content wysiwyg-content">
Hi,<br />
<br />
I have a CWnd derived class that has to be a template class:<br />
template &lt;UINT COLUMNS&gt;<br />
class CMyWnd : public CWnd<br />
{<br />
&nbsp; ...<br />
};<br />
<br />
When I try to use the BEGIN_MESSAGE_MAP macro I get compilation errors.<br />
BEGIN_MESSAGE_MAP(CMyWnd, CWnd)<br />
&gt;&gt;&nbsp;error C2955: 'CMyWnd' use of class template requires template argument list.<br />
<br />
What is the right way to write this ?
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Hi,

I have a CWnd derived class that has to be a template class:
template <UINT COLUMNS>
class CMyWnd : public CWnd
{
  ...
};

When I try to use the BEGIN_MESSAGE_MAP macro I get compilation errors.
BEGIN_MESSAGE_MAP(CMyWnd, CWnd)
>> error C2955: 'CMyWnd' use of class template requires template argument list.

What is the right way to write this ?

Template window class - How to map messages ?

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