::EnumWindows in MFC

[burhankhan]

Hi:

I want to use ::EnumWindows() in MFC.
But have a problem in last argument.

I want if i click on a button in dialog box ::EnumWindows() API should call.
I write this code:

void mydialog:nButton1()
{
::EnumWindows((WNDENUMPROC)EnumWindowsProc, LPARAM(this));
}

But i have an error message that this operator should not use in global functions.

So how i gain last argument, what value of last argument (LPARAM) i pass to this function?


Burhan

[Agregat]

Cheat: mydialog * pdialog = this;
::EnumWindows(..., (LPARAM)pdialog);

[greka]

the second parameter in that "EnumWindows()" shold be pointer to some data structure you're willing to fill in by your callback function, say, misc. parameters ot the window you'll find during window enumeration or smth. else.

PHP Code:

BOOL CALLBACK EnumWindowCallBack(HWND hwnd, LPARAM lParam) 
{ 
    FINDWINDOWHANDLESTRUCT * pfwhs = (FINDWINDOWHANDLESTRUCT * )lParam; 
    DWORD ProcessId; 
    CString Title; 
    GetWindowThreadProcessId ( hwnd, &ProcessId ); 

    // note: In order to make sure we have the MainFrame, verify that the title 
    // has Zero-Length. Under Windows 98, sometimes the Client Window ( which doesn't 
    // have a title ) is enumerated before the MainFrame 

    CWnd::FromHandle( hwnd )->GetWindowText(Title);
    if ( ProcessId  == pfwhs->ProcessInfo->dwProcessId && Title.GetLength() != 0) 
    { 
        pfwhs->hWndFound = hwnd;
        pfwhs->pid = pfwhs->ProcessInfo->dwProcessId;
        return false; 
    } 
    else 
    { 
        // Keep enumerating 
        return true; 
    } 
} 


[burhankhan]

Originally Posted by Agregat

Cheat: mydialog * pdialog = this;
::EnumWindows(..., (LPARAM)pdialog);

I use this:
mydialog * pdialog = this;
::EnumWindows(..., (LPARAM)pdialog);

But have an error:

error C2440: 'type cast' : cannot convert from '' to 'int (__stdcall *)(struct HWND__ *,long)'
None of the functions with this name in scope match the target type

Any Idea?
Burhan

[burhankhan]

Originally Posted by greka

the second parameter in that "EnumWindows()" shold be pointer to some data structure you're willing to fill in by your callback function, say, misc. parameters ot the window you'll find during window enumeration or smth. else.

PHP Code:

BOOL CALLBACK EnumWindowCallBack(HWND hwnd, LPARAM lParam) 
{ 
    FINDWINDOWHANDLESTRUCT * pfwhs = (FINDWINDOWHANDLESTRUCT * )lParam; 
    DWORD ProcessId; 
    CString Title; 
    GetWindowThreadProcessId ( hwnd, &ProcessId ); 

    // note: In order to make sure we have the MainFrame, verify that the title 
    // has Zero-Length. Under Windows 98, sometimes the Client Window ( which doesn't 
    // have a title ) is enumerated before the MainFrame 

    CWnd::FromHandle( hwnd )->GetWindowText(Title);
    if ( ProcessId  == pfwhs->ProcessInfo->dwProcessId && Title.GetLength() != 0) 
    { 
        pfwhs->hWndFound = hwnd;
        pfwhs->pid = pfwhs->ProcessInfo->dwProcessId;
        return false; 
    } 
    else 
    { 
        // Keep enumerating 
        return true; 
    } 
} 


Sir i dont want to fill 2nd parameter lparam in callback function.
I want to know how i call ::EnumWindow() in MFC dialog application.
I try to call this function through a button, but i dont know what i pass to 2nd argument (LPARAM) of this function?

If u have sample project of this then plz send me.

Burhan

[Agregat]

Teh problem is in the first param. As you can deduce from error message.

[greka]

I've already past-ed the sample function to you.

Could you tell me why're you passing "this" ?
If you don't need it then pass NULL as a second param.

The error appears because your "EnumWindowsProc()" does not appropriate to the expected one.
The prototype I've already shown to you, will repeat below:

PHP Code:

BOOL CALLBACK EnumWindowCallBack(HWND hwnd, LPARAM lParam)