C / C++ / MFC Discussion Boards

Neville Franks1-Apr-02 19:00

1-Apr-02 19:00

Shog9 wrote:
WM_AFXFIRST and WM_AFXLAST are #defineed in winuser.h.

Yes I found them there, but I couldn't find them being actually used anywhere.

Shog9 wrote:
Interestingly, i cannot find WM_AFXFIRST/WM_AFXLAST mentioned in MSDN, although the actual range (0x0360 - 0x037F) is documented along with many of the messages themselves.

Thanks a bunch - just what I was looking for. I assumed I'd find:

#define WM_IDLEUPDATECMDUI (WM_AFXFIRST + 3)

but I guess when you're MS you don't need to do sensible stuff like this.

I do use WM_IDLEUPDATECMDUI so that should get be to the bottom of this.

Thanks again.

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

Calling a Dialog from another Dialog

Sayan Mukherjee1-Apr-02 17:08

Sayan Mukherjee

1-Apr-02 17:08

Hi,

I have an MFC executable (.EXE) that is a dialog with some controls.
On double-clicking a particular control, I want a second dialog to
popup and some information to be passed from the calling dialog
to the called dialog.

For this I was trying to use a user-defined windows message
(WM_POPDLG) and passing the information in a malloc-ed pointer
using SendMessage(). The information will be packed into the WPARAM
parameter. Before sending the message, I will create the called
dialog using Create(). I will retrieve the information in the
PreTranslateMessage() function of the called dialog.

WM_POPDLG has been defined as:
#define WM_POPDLG ((WM_APP) + 100)

When I implemented this idea, I found that the PreTranslateMessage()
is not getting called at all. Create() worked fine.

My question:
What do I need to do so that the message sent by SendMessage() hits the
right place and gets processed correctly. Am I missing out something?

Note:
I do not want the called window to become visible before processing
the message in PreTranslateMessage().

With best regards,
Sayan
Email:sayanmukherjee@indiatimes.com

Re: Calling a Dialog from another Dialog

Prem Kumar1-Apr-02 17:16

Prem Kumar

1-Apr-02 17:16

The way of handling the messages is by creating handler
for that message. like using

ON_MESSAGE(WM_POPDLG,OnPopDlg)

Dont use the 'PreTranslateMessage'.
Also the 'SendMessage' will not return unless
the message is processed.
But i think u could set the information in the
dialog using, member variables like
CSecondDlg *pdlg = new CSecondDlg(this) ;
pDlg->m_Data = Data ;//Set the Data u want
pDlg->Create(..) ; //Then call create

The Send message I think only needs to be used if u
have to communicate with a window created by
another module, or in another process.

Re: Calling a Dialog from another Dialog

Sayan Mukherjee2-Apr-02 0:11

Sayan Mukherjee

2-Apr-02 0:11

Hi,

Thank you for your reply.

Why is it that PreTranslateMessage() should not be used? All messages to the
window pass through this function. Isn't it the obvious place to trap the
working of a message? Or, is it reserved for system messages only?

I have tried the code with PreTranslateMessage() and it is not just working.
The code inside is just not getting called for the user-defined message. All
other messages are passing through the function as expected.

Am I missing out something?

With best regards,
Sayan
Email:sayanmukherjee@indiatimes.com

Re: Calling a Dialog from another Dialog

Paul M Watt1-Apr-02 17:46

Paul M Watt

1-Apr-02 17:46

If you are creating a dialog class that is derived from CDialog, you can simply add a member variable in the CDialog derived class, set that member with your allocated data in the main dialog before you display your second dialog. Then you will be able to access that data in your OnDialogInit handler of your second dialog.

If you are simply calling CreateDialog or DialogBox to display your dialog, then call CreateDialogParam, or DialogBoxParam instead and set the dwInitParam to the allocated data pointer. In your OnInitDialog handler, the LPARAM of that message will be this pointer.

volume control

1-Apr-02 16:23

Can anybody let me know ow i can go about adding a simple volume control to my dialog window application. I am using VS 6.0.
Thanks Big Grin | :-D

Re: volume control

Prem Kumar1-Apr-02 16:56

Prem Kumar

1-Apr-02 16:56

What exactly do u want ?
The UI element or how to control the
volume ?

CHtmlView Question

1-Apr-02 15:53

Hello,

I was writing a Browser Shell today, for a learning project. And Navigating to the address was giving me all kindsa errors. First shell i created was a MDI, The method i used to nav to the new address didnt work completely, Then i tried it with a SDI, and it worked as long as you did somthing befor entering a new string to navigate too(like right clicking inside the app somehwere) Well after trying many methods i finally found the Answer to my problem.

But i still idndt understand why the first way i tried wasnt working. Heres what i was using,,

void CMainFrame::NewAddress()
{
CString strcAddress;

m_wndDlgBar.GetDlgItemText(IDC_EADDRESS, strcAddress);

((CHtmlView*)GetActiveView())->Navigate(strcAddress);
}

Why was this not working(crashing @ times, Other times working when clicking on somthing first)

Thanks

Re: CHtmlView Question

Paul M Watt1-Apr-02 16:55

Paul M Watt

1-Apr-02 16:55

If you do not have an active view, then you will be accessing a NULL pointer in this line:

((CHtmlView*)GetActiveView())->Navigate(strcAddress);

If you change your code to this, you will not have a problem:

void CMainFrame::NewAddress()
{
   CString strcAddress;

   m_wndDlgBar.GetDlgItemText(IDC_EADDRESS, strcAddress);

   CHtmlView* pHTMLView = (CHtmlView*)GetActiveView();
   if (pHTMLView)
   {
      // Only access the pointer if the HTML view pointer is valid.
      pHTMLView->Navigate(strcAddress);
   }
}

Re: CHtmlView Question

1-Apr-02 17:57

Ahhhh i c...

Ya i changed the function to look like your example after researching some.

Thx you ..

blinking cursor position

bracoute1-Apr-02 13:19

bracoute

1-Apr-02 13:19

hello, just like getting the mouse cursor coordinates to display a context menu, how can i get the flashing/blinking cursor (use to type text) from a screen (a CEditView )? Can anyone help?

56Kbps of sighs

Re: blinking cursor position

Prem Kumar1-Apr-02 16:55

Prem Kumar

1-Apr-02 16:55

I think what u mean is not the cursor but the 'Caret',
yes u can get the position but to get the exact location
about where it is located viz line, char pos has to be loacted
by you.
Use 'GetCaretPos' to get the pt(co-ords) and convert it into the
character position u need.
Just out of curiosity why do u need this position ?

Re: blinking cursor position

bracoute1-Apr-02 19:14

bracoute

1-Apr-02 19:14

Prem Kumar wrote:
I think what u mean is not the cursor but the 'Caret',
yes u can get the position but to get the exact location
about where it is located viz line, char pos has to be loacted
by you.
Use 'GetCaretPos' to get the pt(co-ords) and convert it into the
character position u need.
Just out of curiosity why do u need this position

First of all thanks you, i want to get this position to display a listbox because i wanna make something just like the visual studio intellisense

Thanks for all

Big Grin | :-D

56Kbps of sighs

Clipboard Copy - multiple formats

Aaron Schaefer1-Apr-02 13:02

Aaron Schaefer

1-Apr-02 13:02

Hi All,

I've got an app that eeds to copy some data to the clipboard. I wrote some code to do this based on a couple of articles I found here, and implemented a copy to clipoboard functionlaity for plain text. So far, so good. But, no I need to copy the same data out as RTF also. Anybody know a simple way I can copy data to the clipboard in multiple formats? Here's sopme code that's not quite working, I am getting a debug assertion the second time through the loop, for the second clipboard format (RTF(:

void CClipboardItem::CopyToClipboard(HWND& hWndNewOwner)
{

// Open the clipboard
OpenClipboard(hWndNewOwner);
EmptyClipboard();

// For every format in the set of supported formats, render data
FormatIterator it;
UINT uFormat;
for(it = m_setFormats.begin(); it != m_setFormats.end(); it++)
{
// Create a shared memory file
CSharedFile sf(GMEM_MOVEABLE | GMEM_SHARE | GMEM_ZEROINIT);

// Render the clipboard data to te shared memory file for the given format
uFormat = *it;
RenderClipboardData(sf, uFormat);

SetClipboardData(uFormat, sf.Detach()); // OOPS! This asserts the second time

}

// All done, let go of the clipboard
CloseClipboard();

}

Any idea why this doesn't work?

Message Reflection

1-Apr-02 13:01

Hey, I'm trying to use Message Reflection for a button I've derived from CButton which is Owner Drawn. I put this in my Message Map:

ON_NOTIFY_REFLECT(WM_MOUSEMOVE,OnMouseMove)

but when I try to goto ClassView it gives me this error:

Parsing Error: Illegal line encountered.
Input Line: ON_NOTIFY_REFLECT(WM_MOUSEMOVE,OnMouseMove)

What am I doing wrong? I'm new to this relecting deal, is there an alternatve?

Message Relfection

1-Apr-02 13:01

Re: Message Relfection

Shog⁹1-Apr-02 13:08

Shog⁹

1-Apr-02 13:08

ON_NOTIFY_REFLECT() only works for WM_NOTIFY messages.
If you've derived a class you don't need to use reflection anyway; just add ON_WM_MOUSEMOVE() and implement OnMouseMove() & you're good to go!

Sometimes i only remember, The days when i was young
Nowadays no one remembers when they were young and stupid...

ADEMA, The Way You Like It

Re: Message Relfection

1-Apr-02 13:11

Well I tried that but I put a break in the OnMouseMove function and it never gets there there?

Re: Message Relfection

Shog⁹1-Apr-02 13:25

Shog⁹

1-Apr-02 13:25

Make sure:

the button is being created/subclassed correctly: do other message handlers in your CButton-derived class get called?
OnMouseMove() has the correct signature: void OnMouseMove(UINT nFlags, CPoint point);
you're moving the mouse over the button

Sometimes i only remember, The days when i was young
Nowadays no one remembers when they were young and stupid...

ADEMA, The Way You Like It

Re: Message Relfection

1-Apr-02 13:30

- Yes, DrawItem and OnCreate both get called (DrawItem repeatedly of course)
- No, OnMouseMove and OnTimer both do not work
- OnMouseMove does have that signature
- Of Course Smile | :)

I was led to believe that if the button was owner drawn it had to be reflected

Re: Message Relfection

1-Apr-02 13:51

Actually, when I turn OwnerDraw off the notifications get through just fine, so I think reflection is necessary...can you lead me through it? thanks in advance

Re: Message Relfection

Shog⁹1-Apr-02 17:57

Shog⁹

1-Apr-02 17:57

Reflection is used by MFC to allow handling messages sent from a control to be handled by the control itself. WM_DRAWITEM is sent by the button control to its parent; however it is cleaner for the code to exist within a class derived from CButton, rather than wherever the CButton-derived class is used. So there is ON_WM_DRAWITEM_REFLECT() which causes DrawItem() to be called.

WM_MOUSEMOVE (OnMouseMove()) and WM_TIMER (OnTimer()) both are sent to the control itself, so they do not need reflection to be handled by the CButton-derived class.

None of this helps with your immediate problem, however Frown | :(

There's nothing special about an Owner-drawn button that keeps it from getting WM_MOUSEMOVE. Double-check (wait, i guess it'd be triple-check) that your class looks something like this:

BEGIN_MESSAGE_MAP(CButtonDerivative, CButton)
   ON_WM_DRAWITEM_REFLECT()
   ON_WM_MOUSEMOVE()
   // ... possibly other entries
END_MESSAGE_MAP()

// ...

void CButtonDerivative::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct)
{
  // ... draw the button
}

void CButtonDerivative::OnMouseMove(UINT nFlags, CPoint point)
{
   // ... handle mouse movement
}

Sometimes i only remember, The days when i was young
Nowadays no one remembers when they were young and stupid...

ADEMA, The Way You Like It

password protect folder

Steven Richardson1-Apr-02 11:03

Steven Richardson

1-Apr-02 11:03

I have a folder that i would like to password protect so you double click on it and you get a password box there needs to be one password that shows the folder and one that shows a different folder and anything else you put in stops you opening it?

How can this be done? Confused | :confused:

Re: password protect folder

dazinith1-Apr-02 11:23

dazinith

1-Apr-02 11:23

this sounds like a windows question more than a coding question? win NT lets you setup folder permissions if you are using NTFS, if your running win 9X then this isn't possible without a 3rd party peice of software

-dz

Re: password protect folder

Steven Richardson1-Apr-02 11:27

Steven Richardson

1-Apr-02 11:27

3rd party software like.....

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