C / C++ / MFC

13-Mar-02 11:13

Say I have an array Stuff[100] how would I make that into a collection class I'm having trouble understanding this. I need to derive it from the CObList in MFC. Thanks for your time guys.

-CDudd Smile | :)

Christian Graus13-Mar-02 11:24

Christian Graus

13-Mar-02 11:24

Why do you need to write your own collection ? What are you making a container of ? I guess pointers to some MFC type ?

There seem to be some examples in MSDN for this, go to msdn.microsoft.com if you don't have MSDN on your PC. Personally, I'd use std::vector, but anyone know knows me remotely knew I'd say that. I'm not familiar with any benefits of CObList, but if it's a container specialised for MFC types, there may well be some, in which case I can't help too much except recommending you check the MSDN.

Christian

The tragedy of cyberspace - that so much can travel so far, and yet mean so little.

"I'm thinking of getting married for companionship and so I have someone to cook and clean." - Martin Marvinski, 6/3/2002

Joaquín M López Muñoz13-Mar-02 11:31

Joaquín M López Muñoz

13-Mar-02 11:31

If what you mean is how to have a CObList of 100 elements, you would have to insert them one by one using CObList::AddTail. The following restrictrions apply:

What you store are not CObjects, but pointers to CObject created with new (CObList assumes responsibility for deleteing them later). In particular, you cannot store simple types like ints or structs not deriving from CObject.
When you retrieve an object stored in a CObList (well, a pointer to it), you have to figure out its actual type and downcast (most usually what you store are not CObjects but some other class derive from this type.)

If you don't mind me evangelizing just a little about STL, why don't you give std::vector or std::list a try? They are way more robust than MFC containers, platform-independent and a lot of fun Smile | :)

Plus, Christian Grauss is writing a series of tutorials on STL to help newbies make a warm start.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

CDuddley13-Mar-02 11:37

13-Mar-02 11:37

Well for a class to use the CObList it has to be derived from CObList. So, if I made a CStuff class how would I derive and, use it to make it like an array?

-CDudd

I don't know how to use STL so that is why I don't use it.

Smile | :)

Joaquín M López Muñoz13-Mar-02 11:44

Joaquín M López Muñoz

13-Mar-02 11:44

Maybe I'm misunderstanding you here. What are you trying to do?

Create a list of 100 CStuff objects.
Define CStuff to behave as a CObist of fixed size (100).
Other.

I don't know how to use STL so that is why I don't use it.

Don't mean to be offensive, but seemingly you don't know how to use CobList either and yet you're trying to.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

CDuddley13-Mar-02 11:52

13-Mar-02 11:52

I need a CStuff class to use all the functions of CObList so I can create a list of 100 CStuff objects.

-CDudd

No offense taken, your right I don't quite understand CObList...yet, but it's just one class others I know how to use. Since I don't know anything at all about STL I don't use it.
Wink | ;)

Christian Graus13-Mar-02 12:04

Christian Graus

13-Mar-02 12:04

You want CStuff to be an object AND to be the container that holds them ? Why ?

If you derive a class for CObList then it will BE a CObjList, which means you can add other functionality, AND use an instance of the class to be a container to hold other instances of it. It sounds like a hell of a bad idea to me though, unless I am missing something.

Christian

The tragedy of cyberspace - that so much can travel so far, and yet mean so little.

"I'm thinking of getting married for companionship and so I have someone to cook and clean." - Martin Marvinski, 6/3/2002

CDuddley13-Mar-02 12:14

13-Mar-02 12:14

Sorry I meant to create 100 Stuffs not CStuffs.

-CDudd Blush | :O

Joaquín M López Muñoz13-Mar-02 12:19

Joaquín M López Muñoz

13-Mar-02 12:19

If I'm getting your point now, what you need to do is having CStuff derive from CObject:

class CStuff: public CObject
{
... // as before
};

Now say your list of CStuffs is called (in a fit of originality) stuffList. So, to enter a new object (up to 100, if that's your wish) you just write:

stuffList.AddTail(new CStuff(/*args here if ctor needs them */));

Hope this is what you were after. Please tell us if it is not.

As for the STL stuff, do not be frightened by its rather awesome aspect. In fact, having a std::list of CStuffs is no harder than with CObList (and you won't have to derive from CObject):

std::list<CStuff> stuffList;
...
stuffList.push_back(CStuff()); // no new here, we store objects rather than pointers to them

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

CDuddley13-Mar-02 14:19

13-Mar-02 14:19

I've been trying for about an hour or so and I'm royally stuck.

Basically I've got a class CShapePt. The program is like a mini paint utility. Whenever the user clicks on the client area it takes the point clicked. Then the next time he/she clicks it draws a line between the two places. The Array it was using was in the MainFrame Header file. I'm not exactally sure how to put the CShapePt object into the MainFrame header file so that the device context can access it. How do you do those code highlighter things? If you need some code to help you see what I'm having trouble explaining I'll be glad to put some snippets on here. Thanks.

-CDudd

VC++ in Visual Studio.NET

Tim Smith13-Mar-02 11:38

Tim Smith

13-Mar-02 11:38

Ditto on the STL stuff.

I might have some strong reservations about many of the STL features, but the containers are GOLDEN...

droooool...

Tim Smith

I know what you're thinking punk, you're thinking did he spell check this document? Well, to tell you the truth I kinda forgot myself in all this excitement. But being this here's CodeProject, the most powerful forums in the world and would blow your head clean off, you've got to ask yourself one question, Do I feel lucky? Well do ya punk?

WM_GETMINMAXINFO

13-Mar-02 10:55

I am handling the WM_GETMINMAXINFO message in my MFC app in the PreTranslateMessage function. When I resize my dialog this message is never sent. Do I have to go about this a different way with MFC or something?

Re: WM_GETMINMAXINFO

Derek Waters13-Mar-02 11:33

Derek Waters

13-Mar-02 11:33

In MFC, providing you're using a CWnd derived class, you should just be able to define a member function like:

afx_msg void OnGetMinMaxInfo(MINMAXINFO *pMMI);

and add:

ON_WM_GETMINMAXINFO()

to your message map. Probably easier than the PreTranslateMessage stuff. I'm not sure why you're not getting the message, though.

------------------------
Derek Waters
derek@lj-oz.com

Re: WM_GETMINMAXINFO

13-Mar-02 11:43

That worked.. Kinda weird that it didn't work in PreTranslateMessage. Thanks for your help.

-Zack

Re: WM_GETMINMAXINFO

Tim Smith13-Mar-02 11:42

Tim Smith

13-Mar-02 11:42

Actually, no, it isn't strange.

PreTranslateMessage is only invoked as part of the normal message pump. Or at least that is what the docs say. I am sure there are a few other instances it is called.

However, my bet is that WM_GETMINMAXINFO is being sent to your window via SendMessage thus the message loop never sees the message. (There are some instances where a SendMessage goes through a message loop, but that is of no concern for 99% of all windows programmers.)

Tim Smith

I know what you're thinking punk, you're thinking did he spell check this document? Well, to tell you the truth I kinda forgot myself in all this excitement. But being this here's CodeProject, the most powerful forums in the world and would blow your head clean off, you've got to ask yourself one question, Do I feel lucky? Well do ya punk?

Rick Crone13-Mar-02 10:36

13-Mar-02 10:36

I'm trying to do something that I think is very simple in VC++ 6.0 in the new VC++ in the Visual Studio.NET. I'm getting strange results. It looks like creating a dialog is creating some HTML code as well as the recource (.rc) and DoModal() seems to be using both of them.

Here are the steps I'm using.
I am creating a VC++ project selecting an MFC Application.

I'm changing these defaults:
Application type = Single Document
Database Support = Header Files Only
ODBC (instead of OLE DB)
In the last step I'm chaning the CView to a CFormView.

The wizard pops a message about no printing support - but I think that's ok.

Now I add a resource, it's a dialog - leave the defaults for this test. Make a class from this resource - DIALOG1.

On my CFormView I add a button [Do It]... add the #include for my DIALOG1.h and add a message handler for this [Do It] button with this simple code:

DIALOG1 d;
d.DoModal();

It runs... but the buttons seem to have shadows and there is a 'TODO: Place controls here' text on my dialog. Hey! That message is not on my dialog resource! Hey! In the HTML folder there is a IDR_HTML_DILAOG1 html file.... that's got buttons and the message that are not on my resource, but are displayed when my dialog 'runs'.

If you move the buttons on the resource you can see that the 'shadows' are really copies of the [OK] and [CANCEL] buttons that are on my dialog.

What's up with this? Is anyone else seeing this stuff?

Rick Crone

Bill Wilson13-Mar-02 14:24

13-Mar-02 14:24

When the wizard creates a dialog, it includes 3 controls in it:

OK Button
Cancel button
Static containing the text 'TODO: Place controls here'

I don't know why you aren't seeing it with the resource editor. It apparently is there, or you wouldn't see it at run time.

I've never seen it create HTML code when inserting a dialog.

Good Luck,
Bill

Rick Crone14-Mar-02 2:59

14-Mar-02 2:59

I agree that is how it worked in VC++ 6.0.

You have built a VC++ 7.0 MFC application and added a dialog to it and you don't see the html?

I have the buttons on the resource, but not the TODO message. I have the buttons and the TODO message on the html code.

Bill Wilson14-Mar-02 6:16

14-Mar-02 6:16

I haven't used VC7 yet. Sorry, I guess I thought you had a question.

Rick Crone14-Mar-02 9:19

14-Mar-02 9:19

Well, I guess I'm the only one trying to use VC++ 7.0 in .NET.

At least it looks that way from the responses my question got.

Unless:
1.) My version is just different from eveyone elses.
2.) There is something about how I'm setting up my application up.
3.) There is something new about creating dialogs.

I don't see how anyone could be using this product.

You are the only one who even answered.

Bill Wilson14-Mar-02 9:55

14-Mar-02 9:55

I guess I'm still having trouble understanding the question.

Are you trying to get a different behaviour out of the wizard? (Not likely)

Are you trying to modify the HTML?

Are you trying to get rid of the html control on the dialog?

Rick Crone14-Mar-02 10:27

14-Mar-02 10:27

I found out a bit more.

In VC++ 7.0 when you create a dialog from a dialog resource the default class in NOT CDialog! It's CHTMLDialog.

I don't know all about this (yet)... but if you want a dialog based on a dialog resource (like it was in VC++ 6.0) when you create the class you need to change it from CHTMLDialog to CDialog.

Maybe we should be using CHTMLDialog for our dialogs in VC++ 7.0, but I haven't found the tools for editing the html like the tools we have for editing a dialog resource. The html code just comes up in text editor like view.

Again, thanks for your interest in trying to help me with this.

Bill Wilson14-Mar-02 12:18