Re: position of dialog box - C / C++ / MFC Discussion Boards

Jeremy Pullicino10-Jun-03 22:06

10-Jun-03 22:06

Hi,

I need to write a control in C++ that is accessible from visual basic, and maybe even internet explorer.

I think that activeX is the way to do it. ( I am not developing .NET)

Would it be best to do it in ATL or MFC, or both?

Thanks,

Jeremy Pullicino
C++ Developer

Homepage

Re: ActiveX control - MFC or ATL

Michael P Butler11-Jun-03 3:02

Michael P Butler

11-Jun-03 3:02

ATL is the best way to write it. That's what ATL is designed to do, especially if you need to use it in IE and require something lightweight that doesn't rely on a lot of external dlls.

The ATL wizards will generate a lot of the boilerplate code for you. Used in conjuction with WTL you should be able to create a control very quickly.

Michael

'War is at best barbarism...Its glory is all moonshine. It is only those who have neither fired a shot nor heard the shrieks and groans of the wounded who cry aloud for blood, more vengeance, more desolation. War is hell.' - General William Sherman, 1879

How use RUNTIME_CLASS for CDateTimeCtrl ??

Thierry Maurel10-Jun-03 21:36

Thierry Maurel

10-Jun-03 21:36

Hello,
I need to enumerate all childs in a dialog, and set them to empty (0, unchecked, "", etc.). To do that, I use the EnumChildWindows function, and in the callback, I try to create a temporary CWnd* object, based on the hWnd. And to perform the correct treatment for each control, I use the IsKindOf (RUNTIME_CLASS (...)).
All is ok, but the CDateTimeCtrl don't work, the linker says :
dateTimeCtrl_pbDlg.obj : error LNK2001: unresolved external symbol "public: static struct CRuntimeClass const CDateTimeCtrl::classCDateTimeCtrl" (?classCDateTimeCtrl@CDateTimeCtrl@@2UCRuntimeClass@@B)

That's strange, because the CDateTimeCtrl contains DECLARE/IMPLEMENT_DYNAMIC so I don't understand the pb ...;
How can I do that ?

Any ideas ?
Thanks in advance

Thierry

Re: How use RUNTIME_CLASS for CDateTimeCtrl ??

Neville Franks10-Jun-03 22:33

Neville Franks

10-Jun-03 22:33

I don't think it is such a good idea using MFC RUNTIME_CLASS for this. I use a combination of GetWindowLong( hWnd, GWL_STYLE ) and GetClassName( .. ) to work out what type a control is. This is straight Windows API stuff and doesn't rely on MFC. It is also more efficent than creating temporary CWnd objects etc.

Neville Franks, Author of ED for Windows. Free Trial at www.getsoft.com

Re: How use RUNTIME_CLASS for CDateTimeCtrl ??

Thierry Maurel10-Jun-03 22:40

Thierry Maurel

10-Jun-03 22:40

I agree with you, that was my primary way, but the GetClassName seems more efficient. So I'll use it.
Thank you for your answer.

Thierry

position of dialog box

chris!10-Jun-03 18:40

chris!

10-Jun-03 18:40

will like to know if there are other ways to position my newly created dialog boxes (ie to have them open at the bottom right hand corner of window for instance). Is there another way other than using SetWindowPos?

thanks

Re: position of dialog box

valikac10-Jun-03 19:23

valikac

10-Jun-03 19:23

One solution is the save the window's position in the registry upon exit. Another solution is MoveWindow().

Kuphryn

Re: position of dialog box

Majid Shahabfar10-Jun-03 19:51

Majid Shahabfar

10-Jun-03 19:51

Hi,
If you would like to show your dialog box in center of the window use CenterWindow() in OnInitDialog function of your dialog based class.

How to cancel the CADORecordset.AddNew() action

winnew10-Jun-03 18:34

winnew

10-Jun-03 18:34

CADORecordset m_rs;
//m_rs is opened
m_rs.AddNew();

How to cancel the AddNew(); Smile | :)

Re: How to cancel the CADORecordset.AddNew() action

Toni7810-Jun-03 18:49

Toni78

10-Jun-03 18:49

If you are not in batch mode then you can't cancel it (undo your operation). You have to delete it.

m_rs.MoveLast();
m_rs.Delete( adAffectCurrent );

In batch mode you can just use CancelUpdate, or RollbackTransmission(). Now, I am not quite sure about the names of these last two functions, because I haven't used them extensively, but look at the ado recordset functions to figure out their actual names and syntaxes are.

By the way, why do you want to cancel AddNew()? Is it because of an error? Because if you have an error, then you can simply call m_rs.CancelUpdate().

// Afterall I realized that even my comment lines have bugs

How to cancel the CADORecordset.AddNew() action

winnew10-Jun-03 18:33

winnew

10-Jun-03 18:33

CADORecordset m_rs;
//m_rs is opened
m_rs.AddNew();

How to cancel to the AddNew(); Smile | :)

How Do i monitor if a key has been depressed?

Member 40481310-Jun-03 18:11

Member 404813

10-Jun-03 18:11

Same as Title

Re: How Do i monitor if a key has been depressed?

Ryan Binns10-Jun-03 18:19

Ryan Binns

10-Jun-03 18:19

Handle the WM_KEYDOWN message in one of your windows.

Ryan

Being little and getting pushed around by big guys all my life I guess I compensate by pushing electrons and holes around. What a bully I am, but I do enjoy making subatomic particles hop at my bidding - Roger Wright (2^nd April 2003, The Lounge)

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: How Do i monitor if a key has been depressed?

Member 40481310-Jun-03 18:26

Member 404813

10-Jun-03 18:26

hi~` thanks for the reply

i have something like this

BOOL CimgtestDlg::PreTranslateMessage(MSG* pMsg)
{
if(pMsg->message==WM_KEYDOWN)
{
if (pMsg->wParam == VK_SPACE) {
lpreview = 1;
}
if(pMsg->wParam==VK_ESCAPE)
return TRUE;
}
return CDialog::PreTranslateMessage(pMsg);
}
so this means when i press space key lpreview will be set to 1.
if the user keeps pressing space key the lpreview will always be 1.
However, what i want is that when the user doesn't press anything
lpreview will be set to 0. How do i do that?

Thanks

Re: How Do i monitor if a key has been depressed?

Ryan Binns10-Jun-03 18:31

Ryan Binns

10-Jun-03 18:31

Don't do it in PreTranslateMessage()!!

Handle WM_KEYDOWN:

void CimgtestDlg::OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags)
{
    if(nChar == VK_SPACE)
        lpreview = 1; // space key was pressed
    if(nChar == VK_ESCAPE)
        // Do whatever you want here - escape key was pressed
}

To set lpreview to 0 when the the key is not pressed, just handle WM_KEYUP:

void CimgtestDlg::OnKeyUp(UINT nChar, UINT nRepCnt, UINT nFlags)
{
    if(nChar == VK_SPACE)
        lpreview = 0; // space key was released
}

You can also check the state of the space key at any time by using GetKeyState(VK_SPACE). If the return value <0, then the key is pressed, else it is not pressed.

Hope this helps

Ryan

Being little and getting pushed around by big guys all my life I guess I compensate by pushing electrons and holes around. What a bully I am, but I do enjoy making subatomic particles hop at my bidding - Roger Wright (2^nd April 2003, The Lounge)

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: How Do i monitor if a key has been depressed?

Member 40481310-Jun-03 18:33

Member 404813

10-Jun-03 18:33

Thanks for the help.. really appreciated..

Big Grin | :-D

wordxp table

Fool's Garden10-Jun-03 18:05

Fool's Garden

10-Jun-03 18:05

Dear all:

the table in wordXP can merge ,split ,align the cells.
How I create a table like this ?

Any sample code or suggestion will be prefered .

Thanks a lot in advance !

Confused | :confused:

apex bird

Re: wordxp table

Larry J. Siddens11-Jun-03 9:44

Larry J. Siddens

11-Jun-03 9:44

In some of the newer versions of Rich Edit DLL, you can actually create tables. They do have limits tho... Read the MSDN on it and see if it will do what you want.

Before we saw that you can do this, we created one that emulates words table.

Wrongway

how to operate a control of a parent class?

Anonymous10-Jun-03 17:46

Anonymous

10-Jun-03 17:46

i want to add string to a combolistbox of a parent class
who can tell me how to do this .

Re: how to operate a control of a parent class?

valikac10-Jun-03 19:24

valikac

10-Jun-03 19:24

One solution is messages. Send a message to the parent window and have it update the control.

Kuphryn

C++ DLL

vbtester10-Jun-03 17:21

vbtester

10-Jun-03 17:21

I am writing a C++ DLL that needs to return an array of my UDT structure to my VB Application. My problem is I am getting an automation error when I try to delcare any variables which are of the structure type I declared in C++
=====================================
I have a structure defined in C++ as follows
typedef struct structCONTACT
{
char* name;
char* email;
}CONTACT;
======================================
My GetContacts Function is defined as follows
CONTACT* __stdcall GetContacts()
{
CONTACT* c;

blah blah blah...

return c;
}
======================================
In visual basic, I set a reference to my DLL file and type the following
Dim cArr As CONTACT ' Causes Automation Error

cArr = GetContacts() ' Causes Automation Error
======================================

Why does this cause an Automation Error? In my DLL i have a resource file that has this code
1 typelib MyWab.tlb

This allows VB to access my C++ datatype with out having to distribute the .tlb file.

My DLL compiles and VB can see my structure, it can also see my function GetContacts(), however it will not run becase it give the following error:
"Compiler Error: Variable uses an Automation type not supported in visual basic."

I think the char* inside my C++ structure is okay, I beleive the problem is the fact that im trying to return an array of the CONTACT structure, and VB does not like this becase it does not recognize CONTACT as a supported Automation Data Type.

How can I make it a supported Automation DataType?

Thanks in advance Big Grin | :-D

Re: C++ DLL

valikac10-Jun-03 19:27

valikac

10-Jun-03 19:27

In the design, CONTACT structure is not COM compliant data type. One solution is to design a custom proxy/stub for custom marshaling.

Kuphryn

Re: C++ DLL

basementman11-Jun-03 4:10

basementman

11-Jun-03 4:10

Or design your DLL function to accept a variant of type SafeArray. Element 0 is the first string and Element 1 is the second string.

Re: C++ DLL

vbtester11-Jun-03 5:02

vbtester

11-Jun-03 5:02

Thank-you for your reply.

If I am to use SAVEARRAY what would my function signature look like I have not used SAFEARRAY before and do not quite understand the definition in the MSDN. This SAFEARRAY would it actually be an array of CONTACT or how would that actually work?

Thanks again

Re: C++ DLL

vbtester12-Jun-03 7:08

vbtester

12-Jun-03 7:08

Hummm, no one seems to know the answer to this post...
Just an update, I have changed my C++ code so that the GetContacts function no longer returns a CONTACT data structure, instead I pass a reference to a DataStructure in as a parameter.

I then added the following line in the General Declorations Part of VB
Private Declare Function GetContacts Lib "MyWab.dll" (ByRef sPathToWABDLL As String, ByRef c() As CONTACT)

Now im getting a completely different error "Bad DLL calling convention" But if I take out that VB Declare, I get an automation error.

What am I doing wrong? Mad | :mad:

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