C / C++ / MFC

17-Nov-09 2:46

Hi
I'm trying to get some information about the windows that working in the background.
I'm using the GetWindowRect function and it's never show me information.
here is the relevant part of my code:

BOOL CALLBACK EnumChildProc(HWND hwnd, LPARAM lParam) {<br />
<br />
	LPRECT lprect=NULL;<br />
	cout << "hwnd_Child = " << hwnd << endl;<br />
	SetWindowText(hwnd,NULL);<br />
	if(GetWindowRect(hwnd,lprect))<br />
		cout<< lprect->bottom<< endl;<br />
	<br />
	<br />
	<br />
<br />
     return TRUE; // must return TRUE; If return is FALSE it stops the recursion<br />
}

it does change the window's text but doesn't go into the if. any idea why?

by the way how can i find the buttons inside the window?

thanks
Itay

Richard MacCutchan17-Nov-09 3:10

Richard MacCutchan

17-Nov-09 3:10

Using this code : LPRECT lprect=NULL; You are sending a NULL pointer so that will cause GetWindowRect() to fail. Try the following instead:

RECT cRect;
if(GetWindowRect(hwnd, &cRect))
...

and on return cRect should contain the cx and cy values

itay1017-Nov-09 5:23

Re: get the window's rect [modified]

17-Nov-09 5:23

Richard MacCutchan wrote:

RECT cRect;
if(GetWindowRect(hwnd, &cRect))
...

thanks. now it is working.

Code-o-mat17-Nov-09 3:11

Code-o-mat

17-Nov-09 3:11

You can't get the rectangle of windows which do not belong to your own process. However, GetWindowText and SetWindowText do work between different processes. (in case you are enumerating windows of other processes also)

Additionally to what Richard MacCutchan said.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Sometimes you just have to hate coding to do it well. <

modified on Tuesday, November 17, 2009 9:34 AM

Richard MacCutchan17-Nov-09 6:22

Richard MacCutchan

17-Nov-09 6:22

Code-o-mat wrote:
You can't get the rectangle of windows which do not belong to your own process.

Strange, this restriction is not noted in the MSDN documentation, but it is noted in the doc for Get/SetWindowText()!

Code-o-mat17-Nov-09 6:34

Code-o-mat

17-Nov-09 6:34

I might be wrong but i think i once wanted to get the rectangle of such windows too and i couldn't get it to work so i googled around and found out that the reason was indeed that GetWindowRect can't cross processes.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Sometimes you just have to hate coding to do it well. <

CPallini17-Nov-09 3:15

17-Nov-09 3:15

itay10 wrote:
LPRECT lprect=NULL;

itay10 wrote:
if(GetWindowRect(hwnd,lprect))

You cannot do this.
The pointer must hold the address of a valid struct.

change to:

RECT rect;
//..
if(GetWindowRect(hwnd ,&rect))
//..

BTW: why aren't you calling GetLastError?
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

itay1017-Nov-09 5:21

17-Nov-09 5:21

thanks all it worked!

CPallini wrote:
BTW: why aren't you calling GetLastError?

I don't know, never tried. how can it help?

David Crow17-Nov-09 5:55

David Crow

17-Nov-09 5:55

itay10 wrote:
how can it help?

Seriously? Did you read the docs to see what it does? Since the condition in the if test evaluated to false, that would indicate that GetWindowRect() returned zero.

"Old age is like a bank account. You withdraw later in life what you have deposited along the way." - Unknown

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

itay1017-Nov-09 7:06

17-Nov-09 7:06

i debugged it and i knew the returned value was zero, the question was why?

David Crow17-Nov-09 7:08

David Crow

17-Nov-09 7:08

Calling GetLastError() would have likely told you why.

CPallini17-Nov-09 6:03

17-Nov-09 6:03

itay10 wrote:
CPallini wrote:
BTW: why aren't you calling GetLastError?

I don't know, never tried. how can it help?

Oh, don't worry about, it's a decorative function... Roll eyes | :rolleyes:

Richard MacCutchan17-Nov-09 5:39

Richard MacCutchan

17-Nov-09 5:39

CPallini wrote:
BTW: why aren't you calling GetLastError?

Real men don't need GetLastError(); what do you think CodeProject is for? Laugh | :laugh:

CPallini17-Nov-09 5:47

Examples of SaveAs in winapi / c++

17-Nov-09 5:47

Richard MacCutchan wrote:
Real men don't need GetLastError();

You're right: real women need GetHisLastError, while real men do need AdmitLastError.
Big Grin | :-D

Nicola Curran17-Nov-09 2:07

17-Nov-09 2:07

Hi, I'm aiming to do something like instance a save as dialogue box have a user add input. Retrieve the file name and create the file based on the input. This is what I have so far:

OPENFILENAME _openfile;
ZeroMemory(&_openfile, sizeof(OPENFILENAME));
_openfile.lStructSize = sizeof(OPENFILENAME);
_openfile.lCustData = (DWORD)NULL;
_openfile.hwndOwner = GetFocus();
_openfile.lpstrFile = tmp;
_openfile.lpstrInitialDir = strcat(buffer, "\\Desktop\\");
_openfile.lpstrDefExt = ".xml";
_openfile.lpstrFilter = "Extensible Markup Language (*.xml)";

bool success = false;
success = GetSaveFileName(&_openfile);

HANDLE file = CreateFile(_openfile.lpstrFile, GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ, NULL, CREATE_NEW, FILE_ATTRIBUTE_NORMAL,
NULL);

What I was wondering is if anyone knew of an example of how to do this on codeproject. I can't seem to find one. Thanks for anything you can suggest. Nicola x

CPallini17-Nov-09 2:21

17-Nov-09 2:21

What is your trouble about?
Smile | :)

Nicola Curran17-Nov-09 2:38

17-Nov-09 2:38

I cant find a full example of using GetSaveFileName, and how I can then get the file name from that (which I assumed was supposed to be passed by reference back to me?)

Have you come across an article that might help? Effectively, All i want to achieve is

Click Save as button -> GetSaveFileName()

CreateFile(filename);

but I don't know how to get the file name from the dialogue.

CPallini17-Nov-09 2:46

17-Nov-09 2:46

Not sure I got you, anyway an usage example is here [^].
Smile | :)

Nicola Curran17-Nov-09 3:10

17-Nov-09 3:10

OMG I dispare! The reason it wasn't working is because I'm a moron....I mean because I wasn't adding .xml to the end of the supplied file name in the gui. Doh!

Nicola Curran17-Nov-09 3:13

17-Nov-09 3:13

No wait, maybe it was something else....Here is the working code for any searching people:

char buffer[256]={""};
char tmp[256]={""};
tmp[0] = '\0';
GetEnvironmentVariable("USERPROFILE", buffer, sizeof(buffer));

OPENFILENAME _openfile;
ZeroMemory(&_openfile, sizeof(OPENFILENAME));
_openfile.lStructSize = sizeof(OPENFILENAME);
_openfile.hwndOwner = GetFocus();
_openfile.lpstrFilter = "Extensible Markup Language (*.xml)";
_openfile.lpstrFile = tmp;
_openfile.nMaxFile = sizeof(tmp)/sizeof(*tmp);
_openfile.lpstrFileTitle = "Save As ...";
_openfile.lCustData = (DWORD)NULL;
_openfile.lpstrInitialDir = strcat(buffer, "\\Desktop\\"); /*virtalis_diagnostic_info.xml");*/
_openfile.lpstrDefExt = "xml";

bool success = false;
success = GetSaveFileName(&_openfile);
DWORD error = CommDlgExtendedError();

HANDLE file = CreateFile((LPTSTR)_openfile.lpstrFile,
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ, NULL, CREATE_NEW, FILE_ATTRIBUTE_NORMAL,
NULL);

I hope this helps some idot n00b like myself!

Nicola Curran17-Nov-09 3:13