|
Not right. When you dynamically create a menu, it has no items: you have to use the AppendMenu method to add, at least a menu item to it.
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?!
-- C++ FQA Lite
|
|
|
|
|
I suspect you are getting your terminology wrong, and as suggested please show the code that you are having problems with, and why you think it needs this id.
|
|
|
|
|
Richard MacCutchan wrote: I suspect you are getting your terminology wrong, and as suggested please show the code that you are having problems with, and why you think it needs this id.
Yes, there was a terminology wrong from my side..... The misunderstanding was done when I tried to initialize a CXTPBrowseButton from Codejock's framework and I needed a resource ID menu but I only create that menu dynamically.
The code example I tried to customize is :
m_edit1.Initialize(this, BES_XTP_POPUPMENU, IDR_POPUP);
and is declared like
virtual bool Initialize(CWnd* pParentWnd, DWORD dwBStyle, UINT nMenu = 0, int nSubMenuIndx = 0);
It seems that I dont have an option in this situation to pass an object handle !!!!
My worng thoughts was that I just needed an ID just to make an object unique for the internal use of the MFC framework but I didn't thought that it was merely a unique RESOURCE ID.
Thanks for clarifying this..... I just dazed and confused.
sdancer75
|
|
|
|
|
I have never come across Codejock so cannot offer any suggestions.
|
|
|
|
|
That's the id of the associated command, which is not the same as resource id. But maybe that is what the OP is really asking for.
|
|
|
|
|
You are right, of course (on both the points, I hope).
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?!
-- C++ FQA Lite
|
|
|
|
|
I am trying to pass a class I wrote to sprintf(). Not the class itself actually, but a pointer to a string the class holds.
With the VC++ CString class it works fine:
sprintf(t, "%s", cst);
But with my class, it either crashes the program or puts garbage into the t buffer:
sprintf(t, "%s", c);
Unless I use casting, and then it works ok:
sprintf(t, "%s", (char *)c);
What is my class missing? Some kind of an operator?
Here is my code:
class C1
{
public:
C1()
{
sprintf(m_Data,"C1 class");
}
operator char *() { return m_Data; }
private:
char m_Data[100];
};
int main(int argc, char* argv[])
{
char t[1000]="";
C1 c;
CString cst("Test c string");
sprintf(t, "%s", cst);
sprintf(t, "%s", c);
return 0;
}
|
|
|
|
|
Crazy Joe Devola wrote: What is my class missing? Some kind of an operator? You are missing nothing: Try the following statement:
char * p = c;
However the cast (either the one you used or the static_cast<char *>() ) is required in sprintf due to its signature (the type of its variadic arguments is established dynamically based on the fmt parameter) the char*() operator must be explicitely called.
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?!
-- C++ FQA Lite
|
|
|
|
|
Thank you.
Yes, char * works.
However, when i use the CString class as in my example, no casting or conversion is required at all. What does the CString class have that my C1 does not? (obviously a lot but specifically for what I am trying to do...)
|
|
|
|
|
You are right, of course. And that is, at the moment, a mystery to me too.
However, have a look at this MSDN page: CString::operator LPCTSTR[^].
That's make me guess in your actual code m_Data is not the unique (and not the first) data member.
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?!
-- C++ FQA Lite
|
|
|
|
|
I just tested OP's code (without the CString - no MFC or ATL) and it sends the actual C1 object as the last parameter, so the pointer will be rubbish. I also would like to know how CString manages to coerce the () operator without a cast.
|
|
|
|
|
It is not rubbish, in my test (VS2012 ). It is pointer to the C1 object, having the same address of its first data member (m_Data ) in this simple case, so everything goes right (of course if you insert, before m_Data , another member variable, for instance an int , the sprintf gets some garbage).
In the linked MSDN page they indded suggest to explicitely cast the CString object when used as sprintf parameter.
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?!
-- C++ FQA Lite
|
|
|
|
|
Interesting. I used VS2010 Express, and copying OP's code, it copies the entire object onto the stack, thus the 'pointer' is garbage. When I use a cast it pushes the address of the object onto the stack and works as it should. More testing required ...
|
|
|
|
|
See my answer to OP below.
|
|
|
|
|
Well I have noticed,
VC 2012 has different parsing and scanning rules than earlier versions. The question is: Did the rules change in the standard, or was it incorrectly implemented by Microsoft.
Bram van Kampen
|
|
|
|
|
OK, I finally figured it out. CString is a bit more of a sophisticated class, and will not use a fixed length buffer for its data. It uses a dynamically allocated one, and as long as that is the first data item in the class definition, the sprintf call will work; although it is luck rather than anything else. You can check this out with the following code:
class C1
{
public:
C1()
{
m_Data = (char*)malloc(100);
sprintf(m_Data,"C1 class");
}
operator char *() { return m_Data; }
private:
char* m_Data;
};
When you now use the object without the cast, it just copies the object's data onto the stack, and since this data is a pointer to the actual text it all works as you expect. But be aware that this may have unintended consequences, so always use the cast when you want this behaviour.
|
|
|
|
|
However, I don't see the difference on my system (that is it works with m_Data as provided in the OP).
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?!
-- C++ FQA Lite
|
|
|
|
|
Definitely different for me, it only worked with the modified code.
|
|
|
|
|
And apparently the 'strange case' is mine.
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?!
-- C++ FQA Lite
|
|
|
|
|
Well it can't be just you, there must be something else that is not obvious that happens in your compiler. I only managed to work out what was happening on my system by getting the assembler listing from the compiler, so maybe your version of the compiler is different from the two I used.
|
|
|
|
|
Richard MacCutchan wrote: although it is luck rather than anything else
The class has been that way for a very long time because I remember being mystified by exactly the same thing a long, long time ago.
I think when I looked at source for the class it was also set up in such a way that there was in fact basically one data member (there was some tricky code going on.) So even if you used it in the middle everything still works.
Because of that I wonder if there has been a deliberate effort to insure that behavior (versus luck.)
|
|
|
|
|
I thought this was done on pupose on CString for this very reason... (not sure if you mean the luck part referring to CString)
|
|
|
|
|
Albert Holguin wrote: I thought this was done on pupose on CString for this very reason... (not sure if you mean the luck part referring to CString)
Yes that is what I meant - I was supposing that it was possible that it was planned that way from the start.
|
|
|
|
|
Cool! thank you very much Richard.
|
|
|
|
|
Hello
I am a beginner.
i follow dialog split tutorial.
But,
after move the split bar, split bar wasn't refresh.
plz help me
|
|
|
|