Problem sending LVN_COLUMNCLICK notification to a window

[AlexA2]

I'm trying to send a notification to a ListView, but I can't find what am I doing wrong.
This is the code:

#include "stdafx.h"
#include <windows.h>
#include <commctrl.h>
#include <stdio.h>

int second_try(){

DWORD pid = 0;

HWND hWnd=HWND(0x00020756);

GetWindowThreadProcessId( hWnd, &pid );

HANDLE hProcHnd = OpenProcess( PROCESS_VM_OPERATION |PROCESS_VM_READ|PROCESS_VM_WRITE, FALSE, pid );

LPVOID pNMLV = VirtualAllocEx( hProcHnd, NULL, sizeof( NMLISTVIEW ),
MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);


NMLISTVIEW nmlvitem;

nmlvitem.hdr.code = LVN_COLUMNCLICK;
nmlvitem.hdr.hwndFrom = HWND(0x00020770);
nmlvitem.hdr.idFrom = 0;
nmlvitem.iItem=-1;
nmlvitem.iSubItem=2;
nmlvitem.lParam=0;
nmlvitem.ptAction.x=0;
nmlvitem.ptAction.y=0;
nmlvitem.uChanged=0;
nmlvitem.uNewState=0;
nmlvitem.uOldState=0;

DWORD copied = 0;

WriteProcessMemory( hProcHnd, pNMLV, &nmlvitem, sizeof( NMLISTVIEW ), &copied );

SendMessage( hWnd, WM_NOTIFY, (WPARAM)0, (LPARAM)pNMLV ) ;

VirtualFreeEx( hProcHnd, pNMLV, 0, MEM_RELEASE );
return 0;
}

int _tmain(int argc, _TCHAR* argv[])
{
second_try();
return 0;
}

or you can see it here, too:
http://pastebin.com/MJyb4xib

[VictorN]

What does not work?

[AlexA2]

According to Winpector, the application doesn't receive the WM_NOTIFY message.

[VictorN]

According to Winpector, the application doesn't receive the WM_NOTIFY message.

*application * cannot receive any message. Only window can. Which window did you inspect? Is it the parent of the list control window?

[AlexA2]

hWnd belongs to the window that has the SysListView32 (Unicode) class.
And, yes, I used Winspector to inspect messages for this SysListView32 window.

[VictorN]

And, yes, I used Winspector to inspect messages for this SysListView32 window.

But you (I guess!) want to send this WM_NOTIFY to the parent of SysListView32 window. Read the documentation of LVN_COLUMNCLICK notification!

[AlexA2]

Isn't SysHeader32 the child, and SysListView32 the parent that should receive the notification?

[VictorN]

Isn't SysHeader32 the child, and SysListView32 the parent that should receive the notification?

If the notification is HDN_ITEMCLICK or some other HDN_... then yes, it's list view control window that receives all these notifications (because the list view control is the parent of its header control) but all LVN_... notifications are sent to (and supposed to received by) the parent of the list view control.

[AlexA2]

I understand now.

I've changed the hWnd to the parent's one and Winspector did not intercept any message.

[VictorN]

Well, then:
1. Check if window handle (of the "parent") you are sending message to is the same as the actual one.
2. Try Spy++
3. BTW, did you debug your code to be sure it runs OK?

[AlexA2]

How should I do a proper debug? Please tell me what should I check, and I'll post back the values.

[VictorN]

Set a break point at the beginning of you second_try function, then press F5 to start debugging... then use F10 to go step by step through your code to see what happens...

[AlexA2]

http://img254.imageshack.us/i/74380008.png/



Uploaded with ImageShack.us

It doesn't look very good, right?

[VictorN]

Right.
The hProcHnd was not initialized...

[AlexA2]

Why does it say "unused"?
What should I do now?