C / C++ / MFC

6-Jun-02 9:11

Hi everyone,

i tried to use the multimap(STL) but I got an error "fatal error: Cannot open include file: 'multimap' C++" I already installed the all the files that I got from sgi... STL Version 3.3, I installed it in "C:\Program Files\Microsoft Visual Studio\VC98\Include"

Here's my code:

#include <string>
#include <iostream>
#include <multimap>
using namespace std;

struct ltstr
{
bool operator()(const char* s1, const char* s2) const
{
return strcmp(s1, s2) < 0;
}
};

int main()
{
multimap<const char*,="" int,="" ltstr=""> m;

m.insert(pair<const char*="" const,="" int="">("a", 1));
m.insert(pair<const char*="" const,="" int="">("c", 2));
m.insert(pair<const char*="" const,="" int="">("b", 3));
m.insert(pair<const char*="" const,="" int="">("b", 4));
m.insert(pair<const char*="" const,="" int="">("a", 5));
m.insert(pair<const char*="" const,="" int="">("b", 6));

cout << "Number of elements with key a: " << m.count("a") << endl;
cout << "Number of elements with key b: " << m.count("b") << endl;
cout << "Number of elements with key c: " << m.count("c") << endl;

cout << "Elements in m: " << endl;
for (multimap<const char*,="" int,="" ltstr="">::iterator it = m.begin();
it != m.end();
++it)
cout << " [" << (*it).first << ", " << (*it).second << "]" << endl;
}

What could be the problem?

Thanks/Regards
Sidney

Joaquín M López Muñoz6-Jun-02 9:18

Joaquín M López Muñoz

6-Jun-02 9:18

Use #include <map> instead.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Sidney6-Jun-02 11:08

6-Jun-02 11:08

I used the #include <map> and I got 14 WARNINGS to many to enumarate it here Smile | :)

but <map> is for map only right? or is it the same file that I shall include if I used multimap?

here's my code after I changed it to <map>:

#include <string>
#include <iostream>
#include <map>
using namespace std;

struct ltstr
{
bool operator()(const char* s1, const char* s2) const
{
return strcmp(s1, s2) < 0;
}
};

int main()
{
multimap<const char*, int, ltstr> m;

m.insert(pair<const char* const, int>("a", 1));
m.insert(pair<const char* const, int>("c", 2));
m.insert(pair<const char* const, int>("b", 3));
m.insert(pair<const char* const, int>("b", 4));
m.insert(pair<const char* const, int>("a", 5));
m.insert(pair<const char* const, int>("b", 6));

cout << "Number of elements with key a: " << m.count("a") << endl;
cout << "Number of elements with key b: " << m.count("b") << endl;
cout << "Number of elements with key c: " << m.count("c") << endl;

cout << "Elements in m: " << endl;
for (multimap<const char*, int, ltstr>::iterator it = m.begin();
it != m.end();
++it)
cout << " [" << (*it).first << ", " << (*it).second << "]" << endl;
}

Thanks/Regards
Sidney

Christian Graus6-Jun-02 11:38

Christian Graus

6-Jun-02 11:38

There is a known issue with VC6 sucking that means you will get warnings unless you #pragma them away. The problem is VC, not STL.

Christian

I am completely intolerant of stupidity. Stupidity is, of course, anything that doesn't conform to my way of thinking. - Jamie Hale - 29/05/2002

Sidney6-Jun-02 12:18

6-Jun-02 12:18

A bug? humm... MS is bad Smile | :)

did you try running the simple code which used multipam? I need the multimap to work co'z the cannot accomodate my data criteria... can you try running it?

Thanks/Regards
Sidney

Christian Graus6-Jun-02 12:48

Christian Graus

6-Jun-02 12:48

I didn't notice before - using namespace std is BAD. Put using decalrations only for the bits of the namespace you need.

Apart from that the code runs fine except it has exactly the warning I anticipated seeing.

Christian

I am completely intolerant of stupidity. Stupidity is, of course, anything that doesn't conform to my way of thinking. - Jamie Hale - 29/05/2002

Sidney6-Jun-02 13:11

ISEffects - effects for images

6-Jun-02 13:11

Christian Thank you very much!! Smile | :)

now the multimap works great Smile | :)

The warnings are all gone hehehehe! I used an STL.h that I got from a friend. Thank you very much everyone!!!

Thanks/Regards
Sidney

RemoveAll question

6-Jun-02 8:57

I was wondering..do you have to call RemoveAll on the destructor of your CStringArray or CMaps and other collections or do the destructors take care of everything automatically.

I have always maintained this practice since I took an MFC course a couple of years back, but I wasn't 100% sure if this is actually necessary? If it is, then why? shouldn't the destructors take care of everything?

Re: RemoveAll question

C^hris L^osinger6-Jun-02 9:09

C^hris L^osinger

6-Jun-02 9:09

the destructors will call RemoveAll (or equivalent).

-c

Cheap oil. It's worth it!

how to do flicker-free drawing using memory DC

lucy6-Jun-02 9:04

6-Jun-02 9:04

I have an SDI MFC application, and I use OnPaint() to draw something to my view. Since my view is updated very frequently, (less than 1 second), I am thinking of using memory DC to reduce the flickering. I tried this:

{
CPaintDC dc(this);
CDC memDc;
memDc.CreateCompatibleDC(&dc);

// create CPen, CBrush, 
// select them to memDc
// and draw using memDc.Ellipse, memDc.MoveTo, memDc.LineTo
// to get the shapes I need

// transfer to display
dc.BitBlt(0,
          0,
          displayWidth,
          displayHeight,
          &memDc,
          0,
          0,
          SRCCOPY);

// restore memDc
// delete all GDI object (CPen, CBrush)
memDc.DeleteDC();
}

but there is nothing on the display. The MSDN document said that I should select a bitmap to my memDc. I did so with a dummy blank bitmap resource I created using resource editor. After I select it to the memDc, there will only be the dummy bitmap displayed on my screen. How could I get my drawing displayed? Confused | :confused:

ISEffects - effects for images

C^hris L^osinger6-Jun-02 9:08

C^hris L^osinger

6-Jun-02 9:08

you need to create a compatible bitmap and select it into the memDc before you draw to memDc.

-c

Cheap oil. It's worth it!

lucy6-Jun-02 9:19

6-Jun-02 9:19

Thank you for your fast help. Now I got my drawing dislayed on the monitor, but the background is totally black. And it flickers even worse. Frown | :-(

what could be wrong?

lucy6-Jun-02 9:28

6-Jun-02 9:28

let me try OnEraseBkGround.

lucy6-Jun-02 9:41

6-Jun-02 9:41

Got it. After overwrite the OnEraseBkgnd(), no flicker anymore. Happy.. Smile | :)

lucy6-Jun-02 10:00

6-Jun-02 10:00

I still couldn't figure out why the background color turns to be black instead of the default one. could you give me some clue?

Ernest Laurentin6-Jun-02 10:10

Ernest Laurentin

6-Jun-02 10:10

Call FillSolidRect(...) with the memory object.

One good thing about getting older, you don't lose the ages you've been!

lucy6-Jun-02 10:28

6-Jun-02 10:28

now get it. Thank you!