C / C++ / MFC

9-Dec-03 1:57

Hello, i've got a problem with a Combobox as dropdown! If I have changed the Edit Control, I would paste the EnterKey! I have no reaction! How I can find the VK_RETURN ?

please help

Antti Keskinen9-Dec-03 2:39

9-Dec-03 2:39

Umm..

You have a combobox with the 'dropdown' style set. That far I understand. Beyond this sentence your description of the problem becomes simply too illogical to understand. In english: your typing sucks big time Smile | :)

Could you clarify a bit ? What is it that you are actually trying to accomplish ? Must the edit control attached to the combo box be able to handle return keypresses ?

"You cannot paste a 'EnterKey'" That makes no sense. Are you, per chance, willing to paste a string into the edit control, and this string contains a LF-CR (line feed - carriage return) pair or line change formatting ('\n') ?

The more in detail and clearly you can describe your problem, the more better we can help you. Always when posting a message, remember to check it for spelling errors or typoes. A typo can change the context of a sentence completely, making us misunderstand you completely.

-Antti Keskinen

----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.

Wholesaler9-Dec-03 2:49

9-Dec-03 2:49

Ok,
also i have a list ! Bsp: 1
3
25
76
111
546
3333
4711
Then i change manuell the entry! Bsp 56 then i hit "Enter"! -> then i want start onaccept! If then manuell entry not in List! Messagebox: Entry not in List!
else setCursel manuell entry!

.....

RChin9-Dec-03 3:09

RChin

9-Dec-03 3:09

OK I think I know what you're on about.

You can override the CBN_SELCHANGE message for your combobox using ClassWizard (VS6). This will create the OnSelChangeXXX() function handler that gets called wheneveer your user selects a new item from your combo control, or types in a new entry.
You can then use this handler to determine if the entry is already in your list, or not (Where you wanted to popup a message box).

Another way would probably be to set the CBS_DROPDOWNLIST style programatically, or via the resource editor. This will force the user to select items that are in the list instead of entering their own items.

Hope this helps.

I Dream of Absolute Zero

Wholesaler9-Dec-03 3:17

9-Dec-03 3:17

Can i open the select list when everyone change the edit control?

OnEditChange() ?

When the selectlist is open, the Enterkey is OK!

RChin9-Dec-03 3:21

RChin

9-Dec-03 3:21

Now you've lost me again! Unsure | :~

those automated translators are a b*tch aren't they?

I Dream of Absolute Zero

Antti Keskinen9-Dec-03 3:14

9-Dec-03 3:14

Referring to the MSDN, there is no prepared override which allows you to hack into the message stream of a combo box.

However, there is a way. It requires that you derive a new class from CComboBox, and put a message map entry for 'ON_WM_CHAR' messages. Route these messages to a handler function, and if the message contains the virtual key VK_RETURN, you start the copying routine.

In this routine, you first use GetWindowText to get the current text in the combo box's edit control. Then you use a combination of GetCurSel, DeleteString and InsertString methods to replace the currently selected string with the new string you typed in.

The default handler of the VK_RETURN keypress attempts to search for the inserted string in the list. You must override this handler in order to implement custom functionality. Remember to call the base class handler for other keypresses, otherwise your combo box might not work properly.

-Antti Keskinen

----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.

Wholesaler9-Dec-03 3:24

9-Dec-03 3:24

Ok I have forgotten to say, if the entry correct send a message to a server!
Update the Database about time and Date!

I have a subclass DCCombobox!

/* --------------------------------------------------------------------
* Message-Map definieren
* ------------------------------------------------------------------
*/
BEGIN_MESSAGE_MAP(DCComboBox, CComboBox)
ON_WM_KEYUP()
ON_WM_KEYDOWN()
END_MESSAGE_MAP()

int DCComboBox::OnCreate( LPCREATESTRUCT lpCreateStruct ){

return CComboBox::OnCreate(lpCreateStruct);
}

void DCComboBox::OnKeyDown(UINT nChar,UINT nRepCnt,UINT nFlags ) {
CWnd* parent = GetParent();

if( parent )
parent->PostMessage( WM_KEYDOWN,(WPARAM)nChar,
MAKELONG (nRepCnt,nFlags) );

CComboBox::OnKeyDown(nChar,nRepCnt,nFlags);
}

void DCComboBox::OnKeyUp(UINT nChar,UINT nRepCnt,UINT nFlags ) {
CWnd* parent = GetParent();

if( parent )
parent->PostMessage( WM_KEYUP, (WPARAM)nChar,
MAKELONG(nRepCnt,nFlags) );

CComboBox::OnKeyUp(nChar,nRepCnt,nFlags);
}

Antti Keskinen10-Dec-03 2:48

10-Dec-03 2:48

You're simply not making any sense. I am completely loss of what you are trying to do.

Ask a friend of yours to do an accurate translation of what you want to do and post that as a message. Otherwise we cannot help you any further, as we can't understand your motives at all.

The code you posted works correctly, as far as I can tell: it posts a message to the parent window when a keyboard event is received in the combo box control. Is this what you wanted to do ?

What is this 'send a message to server' ? What server ? Time ? Date ?? Database ??? You've completely shaken us. Start forming your problem anew, and this time ask a friend who has qualified english skills to translate it for you, so it will be easier for us to read.

-Antti Keskinen

----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.

DDE and Netscape

Monty²9-Dec-03 1:55

Monty²

9-Dec-03 1:55

i have made an app which connects to IE and Netscape via DDE and tells the currently loaded URL
it is working fine with IE but
not with Netscape
netscape connects with NSShell,NETSCAPE and NSCMDLINE
but doesn't tell the URL
which of these three should i connect too

please Help

Re: DDE and Netscape

Antti Keskinen9-Dec-03 2:59

9-Dec-03 2:59

Looking at the Netscape's DDE Implementation guide (found here[^]), following details are described:

The DDE service name for Netscape browser is 'NETSCAPE'. The request for obtaining information about a page shown in a window can be obtained by sending a WWW_GetWindowInfo request, which is of type XTYP_REQUEST.

You can see these topics yourself by going to the specified web page.

Here is an MSDN link about using DDE for your convinience: Using Dynamic Data Exchange[^]

Hope this helps,
-Antti Keskinen

----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.

multiple list control

abdulsoni9-Dec-03 1:24

abdulsoni

9-Dec-03 1:24

i have 2 list control says IDC_LIST1 and IDC_LIST2.
I am not using class wizard here. I am declaring in header file using afxmessage ie. afx_msg void OnItemclickList1(NMHDR* pNMHDR, LRESULT* pResult);
and on_NOTIFY ie ON_NOTIFY(HDN_ITEMCLICK, 0, OnItemclickList1)
I have one more list control ie IDC_LIST2 when i declare afxmessage and ON_NOTIFY, the control do not go there. it goes only for the first control.
even after giving the proper ID of the control instead of giving zero. I tried using the single function and then by finding out the ID, but it gives the same id for both the control, i dont get the id of the control( it could be id of the view where this control are placed).
what should be declaration in the BEGIN MESSAGE , END MESSAGE MAP. and how do i differentiate between this 2 controls.

abdul

image processing

satadru9-Dec-03 0:59

satadru

9-Dec-03 0:59

hi people ,
any idea about how to convert a jpg/bmp file to .pcx format......
i also have to save the bmp file into vector image format ....any idea about how to go about it???????? Confused | :confused:

Re: image processing

KaЯl9-Dec-03 2:25

I want to export global data in a DLL

9-Dec-03 2:25

Have a look to this[^] article, it may help.

HTH,

K.

Le temps se perd, "Si" n'existe pas
Tous les remords n'y changeront rien
Le temps se perd, "Si" n'existe pas
Donc à présent le choix reste mien

Matthew Busche9-Dec-03 0:54

9-Dec-03 0:54

I found these words in the MSDN: "Global variables in a DLL source code file are global to each process using the DLL." I know this to be true, because the following dll and app work for me:

----- stupidDll.h -----
#ifndef STUPIDDLL_H
#define STUPIDDLL_H
int __declspec(dllexport) getStupidInt();
#endif
-------------------------

----- stupidDll.cpp -----
#include "stupidDll.h"
int x = 7;
int getStupidInt() { return x; }
-------------------------

----- stupidApp.cpp -----
#include "stupidDll.h"
#include "stdio.h
int main() {
printf("%d %d\n", getStupidInt());
return 0;
}
-------------------------

But say I don't want to have to call a function to get at the value of x. Shouldn't there be someway to export the symbol x in the DLL (just like I can export the symbol getStupidInt()) ?

I.e., I want to be able to have something like:

extern int x;

in stupidDll.h so that applications can reference this global data directly. I presume I need some sort of __declspec on the above, but I haven't been able to figure it out yet. In case it matters, the data I want to export are a couple of C++ objects -- not simple ints.

Thanks much,
Matt Busche

KaЯl9-Dec-03 2:18

9-Dec-03 2:18

Have you tried to put in your DLL header the following declaration?

extern __declspec(dllexport) int x;

and in the DLL code:

int x;

PS. IMHO, global variables suck, especially in an OO design.

Le temps se perd, "Si" n'existe pas
Tous les remords n'y changeront rien
Le temps se perd, "Si" n'existe pas
Donc à présent le choix reste mien

Matthew Busche9-Dec-03 6:20

9-Dec-03 6:20

KaЯl,

Yes. Actually that was the first thing I tried. I get:

stupidApp.obj : error LNK2001: unresolved external symbol "int x" (?x@@3HA)
stupidAp/stupidApp.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

And yes, in general I agree global variables (or in my case objects) suck, but if you knew what I was doing, I suspect you might forgive me. But I am not going to defend myself here. Never-the-less I appreciate your response and would be interested in any other ideas you may have.

Thanks,
Matt

KaЯl9-Dec-03 7:00

9-Dec-03 7:00

Hum...The method I indicated works well for me.

Perhaps is there a mix between C and C++ decorations.

I've sent you a small sample, hope this help.

K.

Le temps se perd, "Si" n'existe pas
Tous les remords n'y changeront rien
Le temps se perd, "Si" n'existe pas
Donc à présent le choix reste mien

Matthew Busche9-Dec-03 8:42

9-Dec-03 8:42

KaЯl,

Thanks very much for your sample code! I've got it working now. You never mentioned anything about dllimport! That was my problem. From my experimentation, I now believe the following:

For global data (certainly for built-in data types and I presume this goes for global C++ objects as well), the DLL source code module must declare the data using __declspec(dllexport), BUT the application module must declare the data using __declspec(dllimport). This seems a tad annoying since the header file must look different for the DLL compile and the Application compile.
For functions (and I presume this goes for class declarations as well), the DLL source code must likewise declare the function using __declspec(dllexport), BUT IN CONTRAST TO THE CASE FOR DATA the application can declare the function using __declspec(dllimport), __declspec(dllexport), or nothing at all!

Actually I just found the dllimport/dllexport descriptions in the MSDN that would seem to support my claims, though I find it somewhat cryptic -- the kind of description that makes sense only after you already know what it's trying to describe. Maybe I'm just mentally slow or lazy. I will have to read the entire section a time or two to see what I can learn.

Anyway, here is what I did for my source code to get this to work.

----- stupidDll.h -----
#ifndef STUPIDDLL_H
#define STUPIDDLL_H
#ifndef DllDecl
#define DllDecl __declspec(dllimport)
#endif
int DllDecl getStupidInt();
extern DllDecl int x;
#endif
-------------------------

----- stupidDll.cpp -----
#define DllDecl __declspec(dllexport)
#include "stupidDll.h"
int x = 8;
int foo = 7;
int getStupidInt() { return foo; }
-------------------------

----- stupidApp.cpp -----
#include "stupidDll.h"
#include "stdio.h"
int main(){
printf("%d %d\n", getStupidInt(), x);
return 0;
}
-------------------------

As you can see, my DllDecl macro normally expands to __declspec(dllimport); however, I predefined the DllDecl macro in StupidDll.cpp before the #include "StupidDll.h" to force it to instead expand to __declspec(dllexport).

Thanks again for your help. It was most helpful.

Matt

KaЯl9-Dec-03 9:38

9-Dec-03 9:38

Matthew Busche wrote:
You never mentioned anything about dllimport
you asked how to export Wink | ;)

You guessed well.
Generally, the technique is the following:

use one header file for both your DLL and your application. In it, define something like

#if _MY_DLL<br />
#define MYDDL_WHATEVER _declspec(dllexport)<br />
#else<br />
#define MYDDL_WHATEVER _declspec(dllimport)

Then, in the header, use:

extern MYDDL_WHATEVER int x;
In the settings of the DLL project, define the preprocessor definition MYDDL_WHATEVER. Et hop, it's done Smile | :)

You could also take a look to this article[^], it may contain useful info.

Matthew Busche wrote:
Thanks again for your help. It was most helpful.
My pleasure, and welcome on Codeproject! Big Grin | :-D

Le temps se perd, "Si" n'existe pas
Tous les remords n'y changeront rien
Le temps se perd, "Si" n'existe pas
Donc à présent le choix reste mien

Alexander ^M.,9-Dec-03 4:53

Alexander ^M.,

9-Dec-03 4:53

use a def file, it's better for C exports.

Don't try it, just do it! Wink | ;-)

Matthew Busche9-Dec-03 6:24