How do I get HWND?

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7 total messages Started by poojo hackma Fri, 16 Feb 2007 20:25

#2582

Author: poojo hackma
Date: Fri, 16 Feb 2007 20:25

7 lines
1160 bytes

I have a thread running in a non-VCL app.

I want to post a WM_PAINT message to the main window from this thread, but I 
need to know the HWND for UpdateWindow(HWND hWnd).

How do I get that from the main window? Once I have it, I can make it 
available to the thread.

Re: How do I get HWND?

#2583

Author: poojo hackma
Date: Fri, 16 Feb 2007 21:02

45 lines
2150 bytes

A search pulled up the code below, but that seems like a lot of work just to 
get the HWND.

Isn't there something basic?

Code:
// -----------------------------------------
HWND  g_hwnd;
int  g_nFound;

BOOL CALLBACK FindHwndFromPID( HWND hwnd, LPARAM lParam) :

HWND GetHwndFromPID ( DWORD dwProcessId)
{
 g_hwnd = NULL;
 g_nFound = 0;
 EnumWindows (  FindHwndFromPID,    ( LPARAM) dwProcessId));
 if ( g_hwnd)  // we found one...
      return ( g_hwnd);
 // nothing found :-(
 return (NULL);
}

BOOL CALLBACK FindHwndFromPID( HWND hwnd, LPARAM lParam)
{
    DWORD   dwPID2Find  =   ( DWORD) lParam;
    DWORD   dwPID       =   0;
    if  (   GetWindowThreadProcessId    (   hwnd,   &dwPID))
        {
            if  (   dwPID   ==  dwPID2Find)
                {
                    g_hwnd  =   hwnd;
                    return  (   FALSE);
                }
        }
    return  (   TRUE);
}

And call 'GetHwndFromPID()' like

Usage:
// -----------------------------------------
HWND hwnd = GetHwndFromPID(GetCurrentProcessId());

which will retrieve the top-level window handle for your app.

Re: How do I get HWND?

#2584

Author: Thomas Maeder [TeamB]
Date: Fri, 16 Feb 2007 22:37

9 lines
1387 bytes

"poojo hackma" <poojo.com/mail> writes:

> A search pulled up the code below, but that seems like a lot of work
> just to get the HWND.
>
> Isn't there something basic?

I have no idea, but I wouldn't trust the programmer's competence too
much since he unnecesarily used global variables.

Re: How do I get HWND?

#2441

Author: DreamChaser
Date: Sat, 17 Feb 2007 02:42

14 lines
1450 bytes

Isn't HWnd a property of the form? I have also seen a lot things that 
indicated that Form->Handle was the HWnd. Just a thought :)
jk

Thomas Maeder [TeamB] wrote:
> "poojo hackma" <poojo.com/mail> writes:
> 
>> A search pulled up the code below, but that seems like a lot of work
>> just to get the HWND.
>>
>> Isn't there something basic?
> 
> I have no idea, but I wouldn't trust the programmer's competence too
> much since he unnecesarily used global variables.

Re: How do I get HWND?

#2443

Author: Ron Sawyer
Date: Sat, 17 Feb 2007 18:24

8 lines
1355 bytes

Did poojo say it was a non-vcl app?

"DreamChaser" <jkofsky@bellsouth.net> wrote in message
news:45d66b86$1@newsgroups.borland.com...
> Isn't HWnd a property of the form? I have also seen a lot things that
> indicated that Form->Handle was the HWnd. Just a thought :)
> jk
>

Re: How do I get HWND?

#2446

Author: Bob Gonder
Date: Sun, 18 Feb 2007 16:52

8 lines
1207 bytes

poojo hackma wrote:

>How do I get that from the main window? Once I have it, I can make it 
>available to the thread.

I use a global.
When WinMain creates the window,  the handle is returned which I then
store in gHWnd.

Re: How do I get HWND?

#2466

Author: poojo hackma
Date: Tue, 20 Feb 2007 15:58

10 lines
1428 bytes

Yes, it is a non-VCL app, so I can't use Form->Handle. Thanks for the 
though, though.

"Ron Sawyer" wrote
> Did poojo say it was a non-vcl app?
>
> "DreamChaser" wrote
>> Isn't HWnd a property of the form? I have also seen a lot things that
>> indicated that Form->Handle was the HWnd. Just a thought :)
>> jk

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