Re: Can I declare a static member in a base class? - C / C++ / MFC Discussion Boards

Michael Dunn16-Feb-02 9:35

16-Feb-02 9:35

Just TAB into the filename edit boxes and change the filenames there.

--Mike--
"There are only a limited number of jobs where they will ask to see the sausage. Most of them are in movies."
-- Christian Graus, 2/11/2002
My really out-of-date homepage
Sonork - 100.10414 AcidHelm
Big fan of Alyson Hannigan.

Points to pixels?

15-Feb-02 18:37

What is the best way to convert

1. points to pixels?

2. cm to pixels?

Re: Points to pixels?

Shog⁹15-Feb-02 19:50

Shog⁹

15-Feb-02 19:50

explanation in MFC, and from memory. take with large pinch of salt
Given a CDC* pDC, an integer specifying points pt, and another integer specifying centimeters cm:

points to pixels
- 1pt = 1/72in
- 1in = 2.54cm
- 1cm = 1000 HIMETRIC units (HIMETRIC = .01mm)
- convert HIMETRIC to pixels using pDC->HIMETRICtoDP()
- so, the conversion would go like this:
```
int px = pt*2540/72;
CSize size(px,px);
pDC->HIMETRICtoDP(&size);
```

cm to pixels (explained above already)

int px = cm*1000;
CSize size(px,px);
pDC->HIMETRICtoDP(&size);

*** note: see documentation for HIMETRICtoDP: in MM_TEXT mapping mode, the measurements gained from this only reflect physical measurements when the ratio of logical coordinates to physical coordinates is 1/1. Not sure when this would matter though.

farewell goodnight last one out turn out the lights

Smashing Pumpkins, Tales of a Scorched Earth

Where is the Battleaxe Document Explorer?

Paul Selormey15-Feb-02 18:34

Paul Selormey

15-Feb-02 18:34

Battleaxe Document Explorer was posted sometime ago, but my bookmark fails.

Best regards,
Paul.

Paul Selormey, Bsc (Elect Eng), MSc (Mobile Communication) is currently Windows open source developer in Japan.

How can I add my own right click menu to a CWebBrowser2

Julia Larson15-Feb-02 17:29

Julia Larson

15-Feb-02 17:29

I've been trying to do this for days. Dead | X|

Anyone have a clue for me? Confused | :confused:

Thank you
-Julie Rose | [Rose]

Re: How can I add my own right click menu to a CWebBrowser2

alex.barylski15-Feb-02 22:38

alex.barylski

15-Feb-02 22:38

I could tell you. But i enjoy watching others squirm. Big Grin | :-D

Just kidding...

I think your referring to IWebBrowser2, C is for classes I is for Interfaces...slight difference. Big Grin | :-D

Anywho...

You have to implement IDocHostUIHandler::ShowContextMenu

By returning S_OK you prevent IE (webbrowser control) from displaying it's default menu. returning S_FALSE allows default behavior.

Basically I think you'd just do your stuff (create menu) and return S_OK

Cheers

"An expert is someone who has made all the mistakes in his or her field" - Niels Bohr

Can I declare a static member in a base class?

nay15-Feb-02 17:04

nay

15-Feb-02 17:04

Ok. I'm writing a 2 pass assembler (for a class). Here's an annotated version of the base class...

class Asm
{
public:
    Asm();
    ~Asm();
protected:
    static HashTable symbolTable;
};

When I derive a class from Asm I get a linking error telling me that HashTable is unresolve. If I remove the static keyword it links fine.
1. So I'm guessing I can't have a static member in a base class because theres a possibility that the bass class will never be created. Is that right?
2. If this is the case then how do I share the symbol table between my derived classes, Pass1 and Pass2?

nay

Re: Can I declare a static member in a base class?

Atul Dharne15-Feb-02 17:36

Atul Dharne

15-Feb-02 17:36

nay wrote:
static HashTable symbolTable;

You have to initialize the HashTable just after your class definition by invoking its constructor maybe like

HashTable Asm::symbolTable();

This will be shared by all the instances of your Asm object.

Atul

Sonork 100.13714 netdiva

Re: Can I declare a static member in a base class?

nay15-Feb-02 17:52

nay

15-Feb-02 17:52

AAAHHHH... thank you very much. I initialized it in my cpp file like this...

HashTable Asm::symbolTable     //compiler didn't like the ()

thanks!

nay

Saving MFC Source :: C++

valikac15-Feb-02 15:10

valikac

15-Feb-02 15:10

Hi.

I started an MFC sample program that Prosise include in his book. I would like to save the source code, but not the enter project. Note that I started the project using AppWizard.

What files do I have to save from the project so I can always open that project up again? Do I have to save the entire probject including Debug? I have not save and/or remove any files yet because I do not work to lose any resource files.

Thanks,
Kuphryn

Re: Saving MFC Source :: C++

Nish Nishant15-Feb-02 15:36

Nish Nishant

15-Feb-02 15:36

Delete the [debug] and [release] folders and back up the rest of the files into a zip.

Nish

Nish was here, now Nish has gone;
He left his soul, to turn you on;
Those who knew Nish, knew him well;
Those who didn't, can go to hell.

I like to Jig | [Dance]

on the Code Project

Sonork ID 100.9786 voidmain
www.busterboy.org

Re: Saving MFC Source :: C++

valikac15-Feb-02 15:54

valikac

15-Feb-02 15:54

Okay. Thanks.

Kuphryn

Re: Saving MFC Source :: C++

Rick York15-Feb-02 16:04

Rick York

15-Feb-02 16:04

You do not the .ncb, .opt, .plg, .aps, or .clw either. All of these are re-generatable.

I wish some of the article writers here were aware of this. Wink | ;)

Converting Visual C++ 4.2 to VC++6.0

LouThePu15-Feb-02 11:29

LouThePu

15-Feb-02 11:29

The boolean variable in 4.2 is an integer(4 bytes)while
on 6.0 it is a character. If I have files stored on VC++ 4.2 and I want to retreive them with a version compiled on 6.0 Wouldn't I have a problem? Did microd=soft take care of this problem somehow?

Louis Norman

Re: Converting Visual C++ 4.2 to VC++6.0

Alvaro Mendez15-Feb-02 12:31

Alvaro Mendez

15-Feb-02 12:31

LouThePu wrote:
If I have files stored on VC++ 4.2 and I want to retreive them with a version compiled on 6.0 Wouldn't I have a problem?

Yep, you should defintely experience problems. A quick-n-dirty workaround is to define bool to int in your stdafx.h.

#define bool int

Regards,
Alvaro

Behind a beautiful woman there's usually a guy who just couldn't wait to get rid of her.

DLL Function in VB

Tim Rymer15-Feb-02 10:18

Tim Rymer

15-Feb-02 10:18

Hey, I've created an ATL object in a .dll, and i am trying to call the function dynamically. How do i need to setup my functions to get them to not give back crappy values (my BSTR="?????????????????????????????")

i tried __stdcall or _export but nothing is working. i also have "ByVal" for the parameter in my function definition in the VB section.

~Timothy T. Rymer

www.digipen.edu
tim.xpertz.com

Re: DLL Function in VB

Paul M Watt15-Feb-02 14:15

Paul M Watt

15-Feb-02 14:15

Is the ATL object a COM object, if so then you simply need to declare your class inside of the type library that is created in your idl file of your project.

Then you can go to the Project | references menu item in your VB project in order to reference your COM object. From there you can use that object in VB just like any other object.

If you are actually exporting an object like you say rather than a function, you would need to instantiate an instance of this object before it can be used, and I do not know of a way to use a C++ object in VB except through COM. If this is what is happening, I am surprised that your program is not crashing.

Don't get WM_COPY in my class?

15-Feb-02 9:33

Hi,
I have a CListBox derived class. I created a context menu which sends a WM_COPY message. I handle this message and copy stuff to clipboard, works fine.

How can I add a CTRL+C key functionality to my class? Pointing me to the right direction would be fine! Well, do I need to create this WM_COPY message by myself (via PreTranslateMessage()) or do I request it somehow?

Thx, Moak

PS: Btw, what is the difference between using ON_MESSAGE() macro or ON_COMMAND() in the MESSAGE_MAP?

Re: Don't get WM_COPY in my class?

Joaquín M López Muñoz15-Feb-02 9:59

Joaquín M López Muñoz

15-Feb-02 9:59

This can be done with a type of resources called accelerators. Go to the resource editor and create a new "Accelerator" object. From here on everything should be clear enough.

As for the difference between ON_MESSAGE and ON_COMMAND, the latter is provided to deal with the special message WM_COMMAND, which can be regarded as comprising many "submessages" (one for each command identifier).

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: Don't get WM_COPY in my class?

15-Feb-02 10:07

Thx, will do!

I just wonder that my CEdit control gets a WM_COPY message, while my CListBox does not (I used the C++ spy to trace messages). Well, is there something special on a edit control that it gets a WM_COPY "for free"? Smile | :)

I would like to generate those standard "accelerators" dynamically... I mean when I use a instance of my CListBox class it should automatically handle CTRL+C and not rely on a manual resource entry. Comfort is what I seek.

Greets, Moak

Re: Don't get WM_COPY in my class?

Joaquín M López Muñoz15-Feb-02 10:36

Joaquín M López Muñoz

15-Feb-02 10:36

I would like to generate those standard "accelerators" dynamically...

I see. Well, then maybe accelerators are not the best solution. Another solution that does not require the user of your class to do any extra work is: handle WM_KEYDOWN, check for the CTRL+C code and send the WM_COPY command when appropriate.
As for the code for CTRL-C, I don't know it right off the top of my hat, but you can just write some OutputDebugString or something in your OnKeyDown to find it out.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: Don't get WM_COPY in my class?

16-Feb-02 6:24

yep, it works. Big Grin | :-D

BOOL CListBoxChat::PreTranslateMessage(MSG* pMsg) 
{
	if(pMsg->message == WM_KEYDOWN)
	{
		TRACE("[LBC] DEBUG WM_KEYDOWN %d\n", pMsg->wParam);

		switch(pMsg->wParam)
		{
		case 'C': 
		case VK_INSERT:
			if(GetKeyState(VK_CONTROL)) 
			   return SendMessage(WM_COPY);
			break;
		}
	}
	return CListBox::PreTranslateMessage(pMsg);
}

Re: Don't get WM_COPY in my class?

Joaquín M López Muñoz16-Feb-02 6:28

Joaquín M López Muñoz

16-Feb-02 6:28

Congratulations! Good luck with your project.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Using a Timer in a Subclassed Control

MJ_Karas15-Feb-02 9:24

MJ_Karas

15-Feb-02 9:24

I have a question of about the use of a system timer within a class. The class
in question is a dialog control class derived from CEdit. What I need to know
is when is the appropriate time to allocate and setup the timer via the call
to SetTimer(). I also need to know when is the appropriate time when to quit the
timer service via the call to KillTimer(). My initial thought was as follows:
Call SetTimer() within my class constructor;
Call KillTimer() within my class destructor;
However I have been thinking if it would be better to add event routines to my
class to support the WM_CREATE and WM_DESTROY and place the calls as follows:
Call SetTimer() within my class OnCreate() event handler;
Call KillTimer() within my class OnDestroy() event handler;
For any of you out there that are more experienced than myself I would ask....
Which of these approaches is better or more apt to work better? And if these
are neither appropriate then what is the proper implementation?
Thank you,
Mike

Re: Using a Timer in a Subclassed Control

Joaquín M López Muñoz15-Feb-02 9:37

Joaquín M López Muñoz

15-Feb-02 9:37

Call SetTimer in CYourEdit::OnCreate. Kill the timer in CYourEdit::OnDestroy (or alternatively, let the timer be killed by the system upon window destruction).

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

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