C / C++ / MFC Discussion Boards

template class friend of another template class

Jerome Conus30-Jan-04 2:36

30-Jan-04 2:36

Hi !

I'd like to know if it's possible to have a template class being friend of another template class to access it's private members.

For example, I'd like the class CTreeNode<T> to be friend of CTree<T>.

I tried several syntaxes :

friend class CTree;

friend class CTree<T>

but it didn't work and I cannot think of another syntax.

How can I do this ?

Thanks !
Jerome

Re: template class friend of another template class

toxcct30-Jan-04 3:11

toxcct

30-Jan-04 3:11

if parameter T is the same in both case, typing that would be good :

<font style="color:blue">template class</font> CTree<<font style="color:blue">typename</font> T> {
    <font style="color:green">//private members...</font>
<font style="color:blue">public</font>:
    <font style="color:green">//...</font>
    <font style="color:blue">friend class</font> CtreeNode<T>;
};

TOXCCT alias Nicolas C.

Right click menu and sending messages

lobanovski30-Jan-04 2:09

lobanovski

30-Jan-04 2:09

hi all,

i'm ashamed to ask such questions, but i can't even figure it out how i can form a query to search for this on the web site or the internet...

1. i need to mimic standard menu items from user-defined ones... let me explain, MFC - standard MDI app (made by the wizard) has few standard menu items (File->Open... for example). Now i made a dilog, which has a button in it, and if the user clcks that button, the handler must act like it's a standard CDocument::OnOpenDocument(...) method. I know, I can construct CFileDialog myself, show it to the user and call CMyDoc::OnOpenDocument(string)... but this will defeat Doc-View approach... What can i do? Just send the message ID_FILE_OPEN... to what window than??

2. right button click and a popup menu appears. what's it name? where can read more about it?

thanks for your time!
alex

debug - is my life style

Re: Right click menu and sending messages

Michael P Butler30-Jan-04 3:39

Michael P Butler

30-Jan-04 3:39

lobanovski wrote:
2. right button click and a popup menu appears. what's it name? where can read more about it?

It is called a "context menu". MSDN and CodeProject have information on them.

Michael

But you know when the truth is told,
That you can get what you want or you can just get old,
Your're going to kick off before you even get halfway through.
When will you realise... Vienna waits for you? - "The Stranger," Billy Joel

template magic - generic callbacks + return values

peterchen30-Jan-04 0:16

peterchen

30-Jan-04 0:16

I'm trying to design some generic callbacks, which works well enough (using similar techniques to Andrescu's ScopeGuards[^]), except for the return value of the callback function.

for void, it#s simple:

struct CCallback { virtual void Call() = 0; }

template <class T>
struct CCallbackFunc_0 : public CCallback
{
   T func;
   CCallbackFunc_0(T func_) : func(func_) {}
   void Call() { func(); }
};

template <class T>
CCallback * CreateCallback(T func_)
{
  return new CCallbackFunc_0<T>(func_);
}

Now I figure I could have two separate branches, one templatized over the return type, but this makes a lot of code, and breaks the nice syntax for using CreateCallback.

Any ideas? Suggestions? Other approaches?

Flirt harder, I'm a coder.

mlog || Agile Programming | doxygen

Re: template magic - generic callbacks + return values

Ryan Binns30-Jan-04 2:23

Ryan Binns

30-Jan-04 2:23

Have you tried using a template, specifying void as the return type? The compiler will spit out a warning (not an error) if a void function returns a value, which you can safely ignore.

Ryan

"Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"

Re: template magic - generic callbacks + return values

peterchen30-Jan-04 3:00

peterchen

30-Jan-04 3:00

I'd like to be able to receive the return value when I do the "Call" through the base class (hence the idea of templating the base class over return type)

Flirt harder, I'm a coder.

mlog || Agile Programming | doxygen

Communicating with Proxy

sinuommen29-Jan-04 22:32

sinuommen

29-Jan-04 22:32

i would like to build an application to communicate with the Proxy. hw to do it

Thank You

Re: Communicating with Proxy

Prakash Nadar29-Jan-04 23:11

Prakash Nadar

29-Jan-04 23:11

I cant give you direct solution, but can give you pointers.

you need to know which proxy you are targeting,
HTTP 1/1 proxy, or sock, etc
mostly it is HTTP 1/1 proxy, so if you could refer the RFC for HTTP you will know how to do it.
regards,
Prakash.

Toughest Steel Comes From Hottest Furnance

a RSS reader

Jerome Conus29-Jan-04 20:46

Jerome Conus

29-Jan-04 20:46

Hi !

I'd like to try to write a very simple RSS reader, but...well, I have no idea where to start.
I've seen that I would need to read an XML file at a specific internet address and parse this XML file, but I'm wondering how other readers work : do I have to poll every x minutes the RSS feed and check for new informations or is there a way to get informed when new info is available ?

Thanks for your help !
Jerome

Re: a RSS reader

Taka Muraoka29-Jan-04 21:43

Taka Muraoka

29-Jan-04 21:43

Jerome Conus wrote:
do I have to poll every x minutes the RSS feed and check for new informations or is there a way to get informed when new info is available

He he. Welcome to the wonderful world of RSS. You've just found one of the many cans of worms that litter this particular landscape. RSS 2.0 has a way of notifying clients when things have changed but nobody bothers with it.

RSS Bandit[^] is open source so that should get you started.

Awasu is, of course, way cooler but I'm not giving away any source Smile | :)

Lets be honest, isn't it amazing how many truly stupid people you meet during the course of the day. Carry around a pad and pencil, you'll have twenty or thirty names by the end of the day - George Carlin

Awasu 1.2 [^]: A free RSS reader with support for Code Project.

URGENT : Black Image???

chio110229-Jan-04 20:16

chio1102

29-Jan-04 20:16

I am trying to interface my C code converted from Matlab with OpenCV.
I tried to get OpenCV to display the image I got from the Matlab
converted C code, but I got a BLACK IMAGE.

- FG is of mxArray * type.
- Using mxGetPr(FG) is supposed to return me the pointer to first
element of FG.
- Then I tried to capture the data in FG in char_ptr.
- And pass in the data in char_ptr into oImage->imageData.
- But all I get is a black image.
- Below is my program:

Can anyone please tell me what is wrong? Sigh | :sigh:

/*assigning the ouput from Matlab converted code to FG*/
mlfAssign(&FG, mlfIndexRef(mclVv(class0, "class"), ".FG"));
int m = mxGetM( FG );
int n = mxGetN( FG );
double * double_ptr = 0;
char char_ptr[240][320];
int i, j, count = 0;

double_ptr = mxGetPr( FG );
for(j=0;j<n;j++){
for(i=0;i<m;i++){
char_ptr[i][j]=(char)(*(double_ptr+count));
}
count++;
}
oimage =="" cvcreateimage(="" cvsize(n,="" m="" ),="" ipl_depth_8u,="" 1="" );
oimage-="">imageData = *char_ptr;
cvSaveImage("outputFG.jpg", oImage);

Please help...

pistachio

i want to get the handle of Dialog , that i created after clicking on a button

Anonymous29-Jan-04 20:10

Anonymous

29-Jan-04 20:10

HI,

i m begginer.
I want to get the handle of a Dialog , that i created after cliking on a button . (for both .. Modless and model)

plz tell me.

thanx

Re: i want to get the handle of Dialog , that i created after clicking on a button

SJolly29-Jan-04 22:03

SJolly

29-Jan-04 22:03

Hello,

The handle is a member of the CDialog object - m_hWnd.

I think this will be NULL until you have called the Create function on a modeless window.

Regards,
Simon

Re: i want to get the handle of Dialog , that i created after clicking on a button

John M. Drescher30-Jan-04 4:51

John M. Drescher

30-Jan-04 4:51

Use GetParent() from the button.

John

iCON OVERLAY

mjvalan29-Jan-04 19:44

mjvalan

29-Jan-04 19:44

I want to use Icon overlay for my files.

What i ve to do with the folowing method of IShellIconOverlayIdentifier

Methods are

GetOverlayInfo
GetPriority
IsMemberOf

web browser plugins

Abhi Lahare29-Jan-04 19:29

Abhi Lahare

29-Jan-04 19:29

Hi all,

I want to create a web browser plugin.But i don't know from where to starts.
Cry | :((

.
Any help to start will be a great

Thanks in advance
AL

Re: web browser plugins

Prakash Nadar29-Jan-04 22:22

Prakash Nadar

29-Jan-04 22:22

Which web broser are you talking about,
if IE there are samples in CodeProject,
if Netscape visit www.fundocode.com

Toughest Steel Comes From Hottest Furnance

Re: IE web browser plugins

Abhi Lahare29-Jan-04 22:44

Abhi Lahare

29-Jan-04 22:44

Hi Prakash,
I want to write IE Browser Plugins.I need something like Adobe Reader.Also I would like to difference between Browser Helper Object and Plugin.
Again,thanks in advance.
AL

Re: IE web browser plugins

Prakash Nadar29-Jan-04 23:09

Prakash Nadar

29-Jan-04 23:09

Sorry i dont have much info about that, but there are ie plugin samples using wtl here on cp.

Toughest Steel Comes From Hottest Furnance

how to convert text into image using VC++6.0

emmatty29-Jan-04 18:39

emmatty

29-Jan-04 18:39

hello firends,

how can i convert text into image programmitically. Cry | :((

Re: how to convert text into image using VC++6.0

basementman30-Jan-04 10:04

basementman

30-Jan-04 10:04

Draw the text into a device context using TextOut or DrawText, then get the bitmap from the device context.

onwards and upwards...

Fill Color in a static control at runtime

swarnamanoo29-Jan-04 18:15

swarnamanoo

29-Jan-04 18:15

I want to fill a chosen color from the color palette in a static control at runtime.How can i do it?

Re: Fill Color in a static control at runtime

amit sebiz29-Jan-04 19:28

amit sebiz

29-Jan-04 19:28

Create a custom derived class of any control and handle the WM_ERASEBACKGROUND in that class.create a solid brush of required color and paint the background(Note do it after calling base classes OnEraseBachGrnd).

how to disable Shift key

wow999929-Jan-04 18:14

wow9999

29-Jan-04 18:14

hi there

1.How to disable Shift key?
2.How to change Shift key function to let it become as same as Ctrl key?

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.